記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The Oxford Knee Score (OKS); Oxford Hip Score (OHS); Knee injury and Osteoarthritis Outcome Score, Joint Replacement (KOOS JR); and Hip disability and Osteoarthritis Outcome Score, Joint Replacement (HOOS JR) are well-validated and widely used short-form patient-reported outcome measures (PROMs) for assessing outcomes after total knee arthroplasty (TKA) and total hip arthroplasty (THA). We are not aware of the existence of any crosswalks to convert scores between these PROMs. We aimed to develop and validate crosswalks that will permit the comparison of scores between studies using different PROMs and the pooling of results for meta-analyses.

Methods: We retrospectively analyzed scores from patients (486 in the knee cohort and 340 in the hip cohort) from the Syracuse Orthopedic Specialists Joint Registry who had completed the appropriate PROMs (OKS and KOOS JR in the knee cohort and OHS and HOOS JR in the hip cohort) as the standard of care before undergoing primary TKA or unicompartmental knee arthroplasty (UKA) between January 9, 2016, and June 19, 2017, or primary THA or hip resurfacing between November 29, 2010, and October 30, 2017, or when returning for postoperative care. Using the equipercentile equating method, we created 4 crosswalks: OKS to KOOS JR, KOOS JR to OKS, OHS to HOOS JR, and HOOS JR to OHS. To assess validity, Spearman coefficients were calculated using bootstrapping methods, and means for actual and crosswalk-derived scores were compared.

Results: There were minimal differences between the means of the known and crosswalk-derived scores. As calculated with the use of bootstrapping methods, Spearman coefficients between the actual and derived scores were strong and positive for both knee arthroplasty crosswalks (0.888 to 0.889; 95% confidence interval [CI], 0.887 to 0.891) and hip arthroplasty crosswalks (0.916 to 0.918; 95% CI, 0.914 to 0.919).

Conclusions: We successfully created 4 crosswalks that allow conversion of Oxford scores to KOOS and HOOS JR scores and vice versa. These crosswalks will allow harmonization of PROMs assessment regardless of which of the short forms are used, which may facilitate multicenter collaboration or allow sites to switch PROMs without loss of historic comparison data.

DOI： 10.2106/JBJS.19.00916.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jos.2023.08.021

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.arth.2024.06.016

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Patients who have spinal stiffness and deformity are at the highest risk for dislocation after total hip arthroplasty (THA). Previous reports of this cohort are limited to antero-lateral and postero-lateral (PL) approaches. We investigated the dislocation rate after direct anterior (DA) and PL approach THA with a contemporary high-risk protocol to optimize stability.

Methods: We investigated patients undergoing THA who had preoperative biplanar imaging from January-December 2019. Patients were identified using radiographic criteria of spinal-stiffness (<10-degree change in sacral slope from standing to seated) and deformity (flatback deformity with >10-degree difference in pelvic incidence and lumbar lordosis). There were 367 patients identified (181 DA, 186 PL). The primary outcome was dislocation rate at 2-years postoperatively. Risk-factors for dislocation were evaluated using logistic regressions (significance level of 0.05).

Results: There were 6 (1.6%) dislocations in the entire cohort, with low dislocation rates for both DA (0.6%) and PL-THA (2.7%). We observed increased utilization of dual mobility with larger outer head bearings (>38 mm) with PL-THA (34.4 versus 5.0%, P < .01) and conversely increased utilization of 32-mm femoral-heads with DA-THA (39.4 versus 7.0%, P < .001). Surgical approach (PL) was not a significant risk-factor for dislocation (odds ratio: 5.03, P = .15). Patients who had a history of lumbar-fusion had 8-times higher odds for dislocation (OR: 8.20, P = .020).

Conclusions: To the best of our knowledge, this is the largest series to date evaluating DA and PL-THA in the hip-spine 2B-group. Our results demonstrate lower dislocation rate than expected with either surgical approach using a high-risk protocol.

Keywords: THA; anterior; instability; posterior; spine; technology.

DOI： 10.1016/j.arth.2023.10.041

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The use of computer navigation or robotic assistance during primary total hip arthroplasty (THA) has yielded numerous benefits due to more accurate component positioning. The utilization of these tools is generally associated with longer operative times and also necessitates additional surgical equipment and personnel in the operating room. Thus, the aim of this study was to evaluate the impact of technology assistance on periprosthetic joint infection (PJI) after primary THA.

Methods: We retrospectively reviewed the records for 12,726 patients who had undergone primary THA at a single high-volume institution between 2018 and 2021. Patients were stratified by surgical technique (conventional THA, computer-navigated THA [CN-THA], or robotic-assisted THA [RA-THA]) and were matched 1:1 with use of propensity score matching. Univariate and logistic regression analyses were performed to compare the rates of PJI within 90 days postoperatively between the cohorts.

Results: After propensity score matching, there were 4,006 patients in the THA versus RA-THA analysis (2,003 in each group) and 5,288 patients in the THA versus CN-THA analysis (2,644 in each group). CN-THA (p < 0.001) and RA-THA (p < 0.001) were associated with longer operative times compared with conventional THA by 3 and 11 minutes, respectively. The rates of PJI after conventional THA (0.2% to 0.4%) were similar to those after CN-THA (0.4%) and RA-THA (0.4%). On the basis of logistic regression, the development of PJI was not associated with the use of computer navigation (odds ratio [OR], 1.8 [95% confidence interval (CI), 0.7 to 5.3]; p = 0.232) or robotic assistance (OR, 0.9 [95% CI, 0.3 to 2.3]; p = 0.808).

Conclusions: Despite longer operative times associated with the use of computer navigation and robotic assistance, the use of these tools was not associated with an increased risk of PJI within 90 days after surgery.

Level of evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.23.00289

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: When evaluating the results of clinical research studies, readers need to know that patients perceive effect sizes, not p values. Knowing the minimum clinically important difference (MCID) and the patient-acceptable symptom state (PASS) threshold for patient-reported outcome measures helps us to ascertain whether our interventions result in improvements that are large enough for patients to care about, and whether our treatments alleviate patient symptoms sufficiently. Prior studies have developed the MCID and PASS threshold for the Hip Disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS JR) and Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) anchored on satisfaction with surgery, but to our knowledge, neither the MCID nor the PASS thresholds for these instruments anchored on a single-item PASS question have been described.

Questions/purposes: (1) What are the MCID (defined here as the HOOS/KOOS JR change score associated with achieving PASS) and PASS threshold for the HOOS JR and KOOS JR anchored on patient responses to the single-item PASS instrument? (2) How do patient demographic factors such as age, gender, and BMI correlate with MCID and PASS thresholds using the single-item PASS instrument?

Methods: Between July 2020 and September 2021, a total of 10,970 patients underwent one primary unilateral THA or TKA and completed at least one of the three surveys (preoperative HOOS or KOOS JR, 1-year postoperative HOOS or KOOS JR, and 1-year postoperative single-item anchor) at one large, academic medical center. Of those, only patients with data for all three surveys were eligible, leaving 13% (1465 total; 783 THAs and 682 TKAs) for analysis. Despite this low percentage, the overall sample size was large, and there was little difference between completers and noncompleters in terms of demographics or baseline patient-reported outcome measure scores. Patients undergoing bilateral total joint arthroplasty or revision total joint arthroplasty and those without all three surveys at 1 year of follow-up were excluded. A receiver operating characteristic curve analysis, leveraging a 1-year, single-item PASS (that is, "Do you consider that your current state is satisfactory?" with possible answers of "yes" or "no") as the anchor was then used to establish the MCID and PASS thresholds among the 783 included patients who underwent primary unilateral THA and 682 patients who underwent primary unilateral TKA. We also explored the associations of age at the time of surgery (younger than 65 years or 65 years and older), gender (men or women), BMI (< 30 or ≥ 30 kg/m 2 ), and baseline Patient-Reported Outcome Measure Information System-10 physical and mental component scores (< 50 or ≥ 50) for each of the MCID and PASS thresholds through stratified analyses.

Results: For the HOOS JR, the MCID associated with the PASS was 23 (95% CI 18 to 31), with an area under the receiver operating characteristic curve of 0.75, and the PASS threshold was 81 (95% CI 77 to 85), with an area under the receiver operating characteristic curve of 0.81. For the KOOS JR, the MCID was 16 (95% CI 14 to 18), with an area under the receiver operating characteristic curve of 0.75, and the PASS threshold was 71 (95% CI 66 to 73) with an area under the receiver operating characteristic curve of 0.84. Stratified analyses indicated higher change scores and PASS threshold for younger men undergoing THA and higher PASS thresholds for older women undergoing TKA.

Conclusion: Here, we demonstrated the utility of a single patient-centered anchor question, raising the question as to whether simply collecting a postoperative PASS is an easier way to measure success than collecting preoperative and postoperative patient-reported outcome measures and then calculating MCIDs and the substantial clinical benefit.

Level of evidence: Level III, therapeutic study.

DOI： 10.1097/CORR.0000000000002857

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Patients undergo total knee arthroplasty (TKA) at widely disparate stages of osteoarthritis, raising the possibility of high heterogeneity among patients enrolled in TKA research studies. Obscuration of treatment effectiveness and other problems that may stem from cohort heterogeneity can be controlled in clinical studies by rigorously defining target patients. The purpose of this review was to determine the extent to which randomized controlled trials (RCTs) on TKA use osteoarthritis severity, as defined by radiographic grade or patient-reported outcome measures (PROMs), in their inclusion criteria, and to investigate potential impact on outcome.

Methods: A search of PubMed, Embase, Scopus, Web of Science, and Cochrane databases used a combination of terms involving TKA, PROMs, and radiographic scoring. A total of 1,227 studies were independently reviewed by 2 screeners for the above terms. RCTs with ≥100 patients (236) and with <100 patients (325) undergoing TKA were analyzed with regard to the specific inclusion criteria and recruitment process.

Results: Among the identified RCTs with ≥100 patients, 18 (<8%, with a total of 2,952 randomized patients) used specific radiographic scoring or PROM thresholds in their inclusion criteria. Eleven of the 18 studies used specific radiographic scoring, such as the Kellgren-Lawrence or Ahlbäck classifications. Three studies used preoperative PROM thresholds: Knee Society Knee Score of <60, Knee Society Function Score of <60, Oxford Knee Score of <20, and Hospital for Special Surgery Score of <60. Among studies with <100 patients, 48 (<15%) used specific inclusion criteria.

Conclusions: The vast majority of RCTs (>85%) did not enroll patients based on disease severity, as measured by PROM score thresholds or radiographic classifications, in their inclusion criteria. The lack of consistent inclusion criteria likely results in heterogeneous cohorts, potentially undermining the validity of RCTs on TKA.

Level of evidence: Prognostic Level I . See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.23.00629

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The use of technology during total knee arthroplasty (TKA) has been associated with more accurate component position and less blood loss. Yet to date, the risk of developing prosthetic joint infection (PJI) associated with computer navigation (CN) or robotic assistance (RA) has not been thoroughly evaluated. This study used propensity score-matching (PSM) in a large cohort of primary TKA patients to compare the rate of PJI following conventional TKA (TKA) versus CN-TKA and RA-TKA.

Methods: We retrospectively reviewed 13,015 knees in 11,727 patients who underwent primary TKA at a single institution from 2018 to 2021. The cohort was stratified into TKA, CN-TKA, and RA-TKA groups. 1:1 PSM was applied to 11,834 patients. Propensity score-matching was performed using logistic regression accounting for age, sex, body mass index, Charlson Comorbidity Index (CCI) score, CCI components, and smoking status. Univariate and multivariable analyses were performed to evaluate differences in surgical time and PJI rate.

Results: Significantly longer median operating times were noted in the RA-TKA group (14 minutes) compared to TKA (P < .001). The PJI rates among matched cohorts were similar among RA-TKA (0.3%), CN-TKA (0.3%), and conventional TKA (0.5%). Multivariable logistic regressions demonstrated that the use of robotic assistance (odds ratio (OR) = 0.5, P = .423) or computer navigation (OR = 0.61, P = .128) was not associated with increased risk of PJI when compared to conventional TKA.

Conclusions: Use of computer navigation and robotic assistance during primary TKA are associated with longer surgical times, but no difference in PJI frequency within 90 days of surgery.

Keywords: complications; computer-navigation; propensity score-matching; prosthetic joint infection; robotic-assistance; total knee arthroplasty.

DOI： 10.1016/j.arth.2023.08.007

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00167-023-07577-8

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Abstract

Purpose: While a wide variety of platelet-rich plasma (PRP) solutions has been developed, innovation continues. In this case, the freeze-dried platelet factor concentrate (PFC-FD) represents another step in PRP refinement. The preparation of PFC-FD at a central laboratory with freeze drying for shelf stabilization should provide additional quality improvements if clinical effectiveness can be demonstrated. Therefore, this study was undertaken to assess the safety and effectiveness of PFC-FD in a prospective open-label trial of patients suffering from knee osteoarthritis (OA).

Methods: 312 consecutive knee OA patients (67% female, mean age 63 ± 10 years), were prospectively recruited in an outpatient knee clinic in Japan. Of these, 10 (3.2%) were lost to follow-up at < 12 months and 17 (5.5%) sought additional knee therapy during the follow-up period. The primary outcome of interest was achievement of the OMERACT-OARSI responder criteria with secondary outcomes of adverse events and PROMs scores 1, 3, 6, 12 months following a single PFC-FD injection.

Results: 285 patients (91%) completed 12 month PROMs. The 17 who sought additional therapy were considered failures leaving an effective sample size of 302 for our primary outcome in which 62% of patients achieved OMERACT-OARSI responder status by 12 months. This varied by OA class with Kellgren-Lawrence grade 4 patients 3.6 times less likely to be responders than grade 1-2 patients. 6% of patients experienced a non-serious adverse event, primarily pain or swelling at the injection site.

Conclusions: PFC-FD provides an observable clinical improvement in 62% of knee OA patients at 12 months post-injection with very little risk of any clinically relevant adverse event. Of course, nearly 40% of patients did not experience an observable clinical improvement, primarily among those with worse KL grades.

Level of evidence: Therapeutic, Level II.

Keywords: Clinical outcomes; Freeze-dried; Knee osteoarthritis; Osteoarthritis; Platelet-rich plasma.

DOI： 10.1007/s00167-023-07414-y

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Existing knee related patient reported outcome measurements (PROMs) have overwhelmingly been developed and validated in western chair-based societies, suggesting a potential for a western bias in PROMs evaluation of patients with knee conditions. We, therefore, endeavor to evaluate the responsiveness of the previously developed culturally relevant Japanese version of the knee injury and osteoarthritis outcome score (JKOOS+).

Methods: We enrolled 114 patients scheduled for total knee arthroplasty (TKA) across 8 knee clinics in Japan. Patients completed the Oxford Knee Score (OKS) and JKOOS + both at the time of enrollment and again 1-year post-TKA. Responsiveness was evaluated using effect size and standardized response mean (SRM). An effect size or SRM >0.8 is considered adequately responsive. We further tested the difference in responsiveness between the original Japanese language KOOS activities of daily living (ADL) domain and the novel Japanese ADL (JADL) domain using the modified Jacknife test.

Results: All domains were adequately responsive with the exception of the KOOS sports and recreation domain, which has previously been ignored by TKA researchers due to its lack of applicability to elderly patients undergoing TKA. The JADL domain outperformed the ADL domain in both effect size (1.51 v. 1.45) and SRM (1.67 v. 1.57) (p < 0.001). The novel Knee Flexion (KF) domain was adequately responsive, though less responsive than other domains except sports and recreation (p < 0.01 v. all other PROMs domains).

Conclusions: The JKOOS+ JADL domain is significantly more responsive than the Europe-developed ADL domain to TKA in Japanese knee patients suffering from knee osteoarthritis (OA). The KF domain, unique to the JKOOS+ and intended to assess difficulty with knee flexion, is adequately responsive to TKA in Japanese patients suffering from OA.

Keywords: Activities of daily living; Cultural sensitivity; Knee flexion; Patient reported outcomes measure.

DOI： https://doi.org/10.1016/j.jos.2023.08.021

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Predicting an arthroplasty patient's discharge disposition, length of stay (LOS), and physical function is helpful because it allows for preoperative patient optimization, expectation management, and discharge planning. The goal of this study was to evaluate the ability of the Risk Assessment and Prediction Tool (RAPT) score to predict discharge destination, LOS, and postoperative mobility in patients undergoing primary total knee arthroplasty (TKA) and total hip arthroplasty (THA).

Methods: Primary unilateral TKAs (n = 9,064) and THAs (n = 8,649) performed for primary osteoarthritis at our institution from 2018 to 2021 (excluding March to June 2020) were identified using a prospectively maintained institutional registry. We evaluated the associations between preoperative RAPT score and (1) discharge destination, (2) LOS, and postoperative mobility as measured by (3) successful ambulation on the day of surgery and (4) Activity Measure for Post-Acute Care (AM-PAC) "6-Clicks" score.

Results: On multivariable analyses adjusting for multiple covariates, every one-point increase in RAPT score among TKA patients was associated with a 1.82-fold increased odds of home discharge (P < .001), 0.22 days shorter LOS (P < .001), 1.13-fold increased odds of ambulating on postoperative day 0 (P < .001), and 0.25-point higher Activity Measure for Post-Acute Care score (P < .001). Similar findings were seen among THAs. A RAPT score of 8 or higher was the most sensitive and specific cutoff to predict home discharge.

Conclusion: Among nearly 18,000 TKA and THA patients, RAPT score was predictive of discharge disposition, LOS, and postoperative mobility. A RAPT score of 8 or higher was the most sensitive and specific cutoff to predict discharge to home. In contrast to prior studies of the RAPT score which have grouped TKAs and THAs together, this study ran separate analyses for TKAs and THAs and found that THA patients seemed to perform better than TKA patients with equal RAPT scores, suggesting that RAPT may behave differently between TKAs and THAs, particularly in the intermediate risk RAPT range.

DOI： 10.1016/j.arth.2023.05.010

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Unplanned hospital readmissions after total joint arthroplasty (TJA) represent potentially serious adverse events and remain a critical measure of hospital quality. Predicting the risk of readmission after TJA may provide patients and clinicians with valuable information for preoperative decision-making.

Questions/purposes: (1) Can nonlinear machine-learning models integrating preoperatively available patient, surgeon, hospital, and county-level information predict 30-day unplanned hospital readmissions in a large cohort of nationwide Medicare beneficiaries undergoing TJA? (2) Which predictors are the most important in predicting 30-day unplanned hospital readmissions? (3) What specific information regarding population-level associations can we obtain from interpreting partial dependency plots (plots describing, given our modeling choice, the potentially nonlinear shape of associations between predictors and readmissions) of the most important predictors of 30-day readmission?

Methods: National Medicare claims data (chosen because this database represents a large proportion of patients undergoing TJA annually) were analyzed for patients undergoing inpatient TJA between October 2016 and September 2018. A total of 679,041 TJAs (239,391 THAs [61.3% women, 91.9% White, 52.6% between 70 and 79 years old] and 439,650 TKAs [63.3% women, 90% White, 55.2% between 70 and 79 years old] were included. Model features included demographics, county-level social determinants of health, prior-year (365-day) hospital and surgeon TJA procedure volumes, and clinical classification software-refined diagnosis and procedure categories summarizing each patient's Medicare claims 365 days before TJA. Machine-learning models, namely generalized additive models with pairwise interactions (prediction models consisting of both univariate predictions and pairwise interaction terms that allow for nonlinear effects), were trained and evaluated for predictive performance using area under the receiver operating characteristic (AUROC; 1.0 = perfect discrimination, 0.5 = no better than random chance) and precision-recall curves (AUPRC; equivalent to the average positive predictive value, which does not give credit for guessing "no readmission" when this is true most of the time, interpretable relative to the base rate of readmissions) on two holdout samples. All admissions (except the last 2 months' worth) were collected and split randomly 80%/20%. The training cohort was formed with the random 80% sample, which was downsampled (so it included all readmissions and a random, equal number of nonreadmissions). The random 20% sample served as the first test cohort ("random holdout"). The last 2 months of admissions (originally held aside) served as the second test cohort ("2-month holdout"). Finally, feature importances (the degree to which each variable contributed to the predictions) and partial dependency plots were investigated to answer the second and third research questions.

Results: For the random holdout sample, model performance values in terms of AUROC and AUPRC were 0.65 and 0.087, respectively, for THA and 0.66 and 0.077, respectively, for TKA. For the 2-month holdout sample, these numbers were 0.66 and 0.087 and 0.65 and 0.075. Thus, our nonlinear models incorporating a wide variety of preoperative features from Medicare claims data could not well-predict the individual likelihood of readmissions (that is, the models performed poorly and are not appropriate for clinical use). The most predictive features (in terms of mean absolute scores) and their partial dependency graphs still confer information about population-level associations with increased risk of readmission, namely with older patient age, low prior 365-day surgeon and hospital TJA procedure volumes, being a man, patient history of cardiac diagnoses and lack of oncologic diagnoses, and higher county-level rates of hospitalizations for ambulatory-care sensitive conditions. Further inspection of partial dependency plots revealed nonlinear population-level associations specifically for surgeon and hospital procedure volumes. The readmission risk for THA and TKA decreased as surgeons performed more procedures in the prior 365 days, up to approximately 75 TJAs (odds ratio [OR] = 1.2 for TKA and 1.3 for THA), but no further risk reduction was observed for higher annual surgeon procedure volumes. For THA, the readmission risk decreased as hospitals performed more procedures, up to approximately 600 TJAs (OR = 1.2), but no further risk reduction was observed for higher annual hospital procedure volumes.

Conclusion: A large dataset of Medicare claims and machine learning were inadequate to provide a clinically useful individual prediction model for 30-day unplanned readmissions after TKA or THA, suggesting that other factors that are not routinely collected in claims databases are needed for predicting readmissions. Nonlinear population-level associations between low surgeon and hospital procedure volumes and increased readmission risk were identified, including specific volume thresholds above which the readmission risk no longer decreases, which may still be indirectly clinically useful in guiding policy as well as patient decision-making when selecting a hospital or surgeon for treatment.

DOI： 10.1097/CORR.0000000000002705

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective: Cervical disc replacement (CDR) is an alternative treatment to anterior cervical discectomy and fusion (ACDF), which is the current gold standard, for degenerative cervical diseases such as cervical spondylotic myelopathy and cervical radiculopathy. CDR has several theoretical benefits over ACDF, including preservation of motion, earlier return to unrestricted activity, and potentially a lower risk of adjacent-segment disease. Recent literature has reported positive clinical results for CDR, but few studies have investigated the long-term risk of revision surgery of CDR versus ACDF. The purpose of this study was to identify and analyze the epidemiological, clinical, and operative risk factors that affect revision rates following single-level CDR and ACDF procedures.

Methods: A retrospective cohort was extracted from the Statewide Planning and Research Cooperative System using ICD-9 and CPT codes. Inclusion criteria were adult patients undergoing primary, subaxial (C3-7), single-level ACDF or CDR for cervical radiculopathy and/or cervical spondylotic myelopathy between 2005 and 2013. Survivability was defined as the time between the index procedure and the presence of a subsequent discharge record for cervical spinal fusion or disc replacement. Statistical analyses were performed using chi-square tests, t-tests, Cox proportional hazards models, and a Kaplan-Meier plot.

Results: A total of 7450 patients were included in this study (6615 ACDF and 835 CDR). When adjusted for patient demographics, the hazard ratios showed no significant differences in the incidence of revision risk between the two cohorts. The CDR cohort had a higher incidence of postoperative dysphagia (p < 0.05). Patients undergoing ACDF had a longer average hospital stay (2.8 vs 1.9 days, p < 0.001). There was no significant difference in time to revision surgery (p = 0.486).

Conclusions: CDR and ACDF have both been shown to be effective treatments for cervical spine disease. CDR patients had a shorter average inpatient hospital stay compared with ACDF patients but tended to experience dysphagia more frequently. There was a tendency toward increased survivability of CDR; however, this was not found to be statistically significant at any time point. The large size and heterogeneity of each cohort and the availability of > 10 years of surveillance data differentiate this study from other published literature. This investigation has limitations inherent to large data analysis studies, including the implementation and inaccuracy of diagnosis and procedural coding; however, this reflects real-world use of coding by practitioners.

DOI： 10.3171/2023.3.SPINE221377

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective: To evaluate the effect of warfarin on blood transfusion and postoperative complications in a low-energy hip fracture population compared with a non-anticoagulated comparison group.

Design: Multicenter Retrospective Cohort.

Setting: Three Urban Level I Academic Trauma Centers.

Patients: Acute, low-energy, native hip fractures in patients 55 years of age or older on chronic warfarin anticoagulation, propensity score matched 1:2 to non-anticoagulated hip fracture patients meeting all other inclusion criteria.

Main outcome measurements: Transfusion and postoperative complication rates.

Results: Two hundred ten anticoagulated hip fracture patients were matched to 420 nonanticoagulated patients. A higher proportion of patients required blood transfusion in the warfarin cohort (52.4% vs. 43.3%, P < 0.001), attributable mostly to the subgroup of patients undergoing arthroplasty. Warfarin patients had higher incidence of overall 90-day complications (47% vs. 38%, P = 0.039) and readmissions (31.4% vs. 8.9%, P < 0.001). Day of surgery international normalized ratio (INR) did not influence transfusions or complications among warfarin patients. Warfarin patients undergoing surgery within 24 hours had no difference in transfusions and had fewer complications compared with those undergoing surgery after 24 hours. On multivariable logistic regression analysis, warfarin use and day of surgery INR were not predictors of transfusion or complications.

Conclusions: Patients on warfarin experienced longer time to surgery and higher incidence of overall transfusion and postoperative complications within 90 days of surgery. However, warfarin use and day of surgery INR was not independently associated with transfusions or complications. The reason for poorer outcomes in warfarin patients remains a topic of further investigation.

DOI： 10.1097/BOT.0000000000002484

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: While transfusion and clinically relevant anemia after elective primary total knee arthroplasty (TKA) are uncommon, there remains a question of who needs postoperative hemoglobin monitoring, especially in the setting of increasing incidence of outpatient TKA. The purpose of this study was to create predictive models for postoperative anemia and blood transfusion to guide clinical decision-making.

Methods: The records of consecutive TKA patients were reviewed from February 2016 to December 2020 at a single institution. Two multivariable logistic regression models, for postoperative anemia (hemoglobin < 10 g/dL) and allogeneic blood transfusion included 8 variables: age, sex, body mass index, preoperative hemoglobin level, tranexamic acid total dose, American Society of Anesthesiologists level, operative time, and drain use. Model performance was assessed using accuracy, area under the curve (AUC), sensitivity, and specificity.

Results: The records of 14,901 patients were included in this study. Patients had a mean (± standard deviation) age of 67.9 ± 9.2 years and mean body mass index of 31.3 ± 6.5 kg/m2. The postoperative anemia model had an accuracy of 88% (95% confidence interval [CI], 87%-89%) and AUC of 0.88 (95% CI, 0.87-0.89). The blood transfusion model had an accuracy of 97% (95% CI, 96%-97%) and AUC of 0.90 (95% CI, 0.87-0.93).

Conclusion: The postoperative anemia and blood transfusion model accurately predicted each outcome. Patients with less than a 5% probability of postoperative anemia may not benefit from a complete blood count at postoperative day 1. Application of these criteria may save the healthcare system hundreds of millions of dollars.

DOI： 10.1016/j.arth.2023.01.018

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Minimal clinically important difference (MCID) defines a meaningful clinical change in patient-reported outcome measures. Patient acceptable symptom state (PASS) provides a patient-reported outcome measures threshold value to indicate a satisfactory clinical state. MCID and PASS for revision total knee arthroplasty (rTKA) are ill-defined. Moreover, it is unknown whether diagnosis influences the likelihood of achieving MCID or PASS. The purpose of this study was to calculate MCID for aseptic rTKA and compare the percentage of patients achieving MCID and PASS per diagnosis.

Methods: An institutional registry of rTKA was used. First-time aseptic rTKA were included. Demographics, revision diagnosis, preoperative Knee Injury and Osteoarthritis Outcome Score, Jr (KOOS Jr), and 1-year postoperative KOOS Jr were recorded. The 1-year postoperative KOOS Jr PASS score was available. MCID was calculated using distribution-based methods. Three hundred fifty eight first-time aseptic rTKAs were analyzed. The 3 most common diagnoses were aseptic loosening (n = 156), instability (n = 109), and stiffness (n = 37).

Results: The mean KOOS Jr 1-year postoperative MCID for rTKA was 10.3. Overall, 75.4% achieved MCID and 56.9% achieved PASS. The percentage of patients per diagnosis achieving MCID and PASS, respectively, were periprosthetic fracture (100, 44), aseptic loosening (94, 60), implant fracture (88, 63), stiffness (60, 38), instability (59, 61), polyethylene wear/osteolysis (57, 57), and metal allergy (44, 33).

Conclusion: Aseptic rTKA MCID is 10.3 for KOOS Jr at 1 year postoperatively. rTKA outcomes vary depending on preoperative diagnosis. Even in diagnoses with a high proportion of MCID achieved, less than 2/3 of patients achieved PASS, suggesting rTKA provides noticeable improvement but may not return patients to a satisfactory state.

DOI： 10.1016/j.arth.2023.01.020

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: Results from recent randomised controlled trials demonstrate the superiority of surgery over physiotherapy in patients with femoroacetabular impingement (FAI) of the hip in early follow-up. However, there is paucity of evidence regarding which factors influence outcomes of FAI surgery, particularly notable is the lack of information on the effect of impingement subtype (cam or pincer or mixed) on patient reported outcomes measures (PROMs). This study aims to evaluate the early outcomes of hip arthroscopy for FAI, and their determinants.

Methods: This is a retrospective analysis of prospectively collected data from the UK Non-Arthroplasty Hip Registry (NAHR) of patients undergoing arthroscopic intervention for FAI between 2012 and 2019. The null hypothesis was that there is no difference in PROMs, based on morphological subtype of FAI treated or patient characteristics, at each follow-up timepoint. The outcome measures used for the study were the iHOT-12 score and the EQ5D Index and VAS 6- and 12-month follow-up.

Results: A cohort of 4963 patients who underwent arthroscopic treatment of FAI were identified on the NAHR database. For all FAI pathology groups, there was significant improvement from pre-operative PROMs when compared to those at 6 and 12 months. Overall, two-thirds of patients achieved the minimum clinically important difference (MCID), and almost half achieved substantial clinical benefit (SCB) for iHOT-12 by 12 months. Pre-operatively, and at 12-month follow-up, iHOT-12 scores were significantly poorer in the pincer group compared to the cam and mixed pathology groups (p < 0.01). Multivariable analysis revealed PROMS improvement in the setting of a higher-grade cartilage lesion.

Conclusion: This registry study demonstrates that hip arthroscopy is an effective surgical treatment for patients with symptomatic FAI and results in a statistically significant improvement in PROMs which are maintained through 12 months follow-up.

DOI： 10.1007/s00167-022-07042-y

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Introduction: Hip resurfacing (HR) requires a larger approach and soft tissue dissection and might therefore be associated with increased blood loss compared to total hip arthroplasty (THA). However, the effect of the adoption of tranexamic acid (TXA) in this setting is unknown. Therefore, the current study compares the blood loss and transfusion requirements between HR and posterior THA in patients receiving TXA.

Materials and methods: This retrospective cohort study included patients undergoing primary, unilateral THA or HR using a posterior approach between February 2016 and 2020 in which TXA was administered. THA and HR patients were propensity score matched using nearest neighbor greedy matching accounting for demographic, health and surgical variables. Postoperative hemoglobin (Hgb) levels and Hgb drop from preoperative to post-operative day (POD) 1 were compared using t-tests and associated risk factors were assessed using linear mixed modelling.

Results: After matching, each cohort consisted of 1395 patients. Cohorts were similar regarding age, sex, BMI, and Charlson Comorbidity Index. No significant differences were found for Hgb levels on POD 1 (12.3 g/dl; p = 0.90) or Hgb drop (2.3 g/dl; p = 0.87). Duration of surgery was significantly longer for HR patients (82 vs 77 min; p < 0.01). Transfusion rate was 0.1% in both cohorts (p = 1.00). Hospital stay was significantly shorter for HR patients (1 vs 2 days; p < 0.01).

Conclusion: HR using a standard TXA regimen is not associated with greater perioperative blood loss than posterior THA and does not result in increased transfusion requirements. Both surgical procedures can be considered equally safe in terms of perioperative blood management when TXA is used.

DOI： 10.1007/s00402-021-04272-6

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.arth.2022.07.025

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objectives: To investigate the impact of COVID-19 on the well-being of surgeons and allied health professionals as well as the support provided by their institutions.

Design: This cross-sectional study involved distributing an online survey through medical organisations, social media platforms and collaborators.

Setting: It included all staff based in an operating theatre environment around the world.

Participants: 1590 complete responses were received from 54 countries between 15 July and 15 December 2020. The average age of participants was 30-40 years old, 64.9% were men and 32.5% of a white ethnic background. 79.5% were surgeons with the remainder being nurses, assistants, anaesthetists, operating department practitioners or classified other.

Main outcome measures: Participants that had experienced any physical illness, changes in mental health, salary or time with family since the start of the pandemic as well as support available based on published recommendations.

Results: 32.0% reported becoming physically ill. This was more likely in those with reduced access to personal protective equipment (OR 4.62; CI 2.82 to 7.56; p<0.001) and regular breaks (OR 1.56; CI 1.18 to 2.06; p=0.002). Those with a decrease in salary (29.0%) were more likely to have an increase in anxiety (OR 1.50; CI 1.19 to 1.89; p=0.001) and depression (OR 1.84; CI 1.40 to 2.43; p<0.001) and those who spent less time with family (35.2%) were more likely to have an increase in depression (OR 1.74; CI 1.34 to 2.26; p<0.001). Only 36.0% had easy access to occupational health, 44.0% to mental health services, 16.5% to 24/7 rest facilities and 14.2% to 24/7 food and drink facilities. Fewer measures were available in countries with a low Human Development Index.

Conclusions: This work has highlighted a need and strategies to improve conditions for the healthcare workforce, ultimately benefiting patient care.

DOI： 10.1136/bmjopen-2021-059873

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.arth.2022.01.044

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Efficient resource management is becoming more important as the demand for total hip arthroplasty (THA) increases. The purpose of this study is to evaluate the ability of linear regression and Bayesian statistics in predicting implant size for THA using patient demographic variables.

Material and methods: A retrospective, single-institution joint-replacement registry review was performed on patients who underwent primary THA from 2005 to 2019. Demographic information was obtained along with primary THA implant data. A total of 11,730 acetabular and 8536 femoral components were included. A multivariable regression model was created on a training cohort of 80% of the sample and applied to the validation cohort (remaining 20%). Bayesian posterior probability methods were applied to the training cohort and then tested in the validation cohort to determine the 1%, 5%, and 10% error tolerance thresholds.

Results: The most predictive regression model included height, weight, and sex (cup: R2 = 0.57, all P < .001; stem mediolateral size [M/L]: R2 = 0.32, all P < .001). Removing weight had a minimal effect and resulted in a more parsimonious model (cup: R2 = 0.56, all P < .001; stem M/L: R2 = 0.32, all P < .001). Applying the posterior probability estimate to the validation cohort in the Bayesian model using height, weight, and sex demonstrated high accuracy in predicting the range of required implant sizes (95.3% cup and 90.4% stem M/L size).

Conclusion: Implant size in THA is correlated with demographic variables to accurately predict implant size using Bayesian modeling. Predictive models such as linear regression and Bayesian modeling can be used to improve operating room efficiency, supply chain inventory management, and decrease costs associated with THA.

DOI： 10.1016/j.artd.2022.02.018

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1302/2633-1462.34.BJO-2022-0003.R1.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1097/BOT.0000000000002251

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.artd.2021.11.021

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00402-021-04272-6

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1097/CORR.0000000000001852

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Debridement, antibiotics, and implant retention (DAIR) failure remains high for total hip and knee arthroplasty periprosthetic joint infection (PJI). We sought to determine the predictive value of the CRIME80 and KLIC for failure of DAIR in acute hematogenous (AH) and acute postoperative (AP) PJIs, respectively.

Methods: We identified 134 patients who underwent DAIR for AH PJI with <4 weeks of symptoms after index arthroplasty and 122 patients who underwent DAIR for AP PJI <90 days from index. In the AH group, 15 patients (11%) failed at 90 days and overall, 33 (25%) had failed by 2 years. In the AP group, 39 (32%) failed at 90 days and overall, 52 (43%) failed by 2 years. Logistic regression models were used to determine the area under the curve (AUC) to establish thresholds using the Youden index.

Results: For the AP cohort, AUCs were below 0.66 for KLIC, Charlson comorbidity index, Elixhauser comorbidity index, and McPherson host grade. For the AH cohort, 90-day AUCs were 0.70 for CRIME80 and below 0.66 for Charlson comorbidity index, Elixhauser comorbidity index, and McPherson host grade. In multivariate analysis controlling for age, sex, and body mass index, the CRIME80 AUC improved to 0.77 at 90 days.

Conclusion: To the authors' knowledge, this study represents the first external validation of the KLIC and CRIME80 for predicting DAIR failure in a North American population. The results indicate that alternative methods for predicting DAIR failure at 90 days and 2 years for acute PJI are needed.

DOI： 10.1016/j.arth.2021.02.039

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00402-021-04043-3.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1001/jamanetworkopen.2021.17581

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Introduction: New technologies exist which may assist surgeons to better predict final intra-operative joint balance. Our objectives were to compare the impact of (1) a predictive digital joint tensioning tool on intra-operative joint balance; and (2) joint balance and flexion joint laxity on patient-reported outcomes.

Materials and methods: Two-hundred Eighty patients received posterior cruciate ligament sacrificing TKA with ultra-congruent tibial inserts using a robotic-assisted navigation platform. Patients were divided into those in which a Predictive Plan with a digital joint-tensioning device was used (PP) and those in which it was not (NPP), in all cases final post-operative joint gaps were collected immediately before final implantation. Demographics and KOOS were collected pre-operatively. KOOS, complications and satisfaction were collected at 3, 6 and 12 months post-operatively. Optimal balance difference between PP and NPP was defined and compared using area-under-the-curve analysis (AUC). Outcomes were then compared according to the results from the AUC.

Results: AUC analysis yielded a balance threshold of 1.5 mm, in which the PP group achieved a higher rate of balance throughout flexion compared to the NPP group: extension: 83 vs 52%; Midflexion: 82 vs 55%; Flexion 89 vs 68%; Flexion to Extension 80 vs 49%; p ≤ 0.003. Higher KOOS scores were observed in knees balanced within 1.5 mm across all sub-scores at various time points, however, differences did not exceed the minimum clinically important difference (MCID). Patients with > 1.5 mm flexion laxity medially or laterally had an increased likelihood of 2.2 (1.1-4.4) and 2.5 (1.3-4.8), respectively, for failing to achieve the Patient Acceptable Symptom State for KOOS Pain at 12 months. Patient satisfaction was high in both the PP and NPP groups (97.4 and 94.7%, respectively).

Conclusions: Use of a predictive joint tensioning tool improved the final balance in TKA. Improved outcomes were found in balanced knees; however, this improvement did not achieve the MCID, suggesting further studies may be required to define optimal balance targets. Limiting medial and lateral flexion laxity resulted in an increased likelihood of achieving the Patient Acceptable Symptom State for KOOS Pain.

DOI： 10.1007/s00402-021-04043-3.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Total hip arthroplasty (THA) patients expect pain relief and functional improvement, including return to physical activity. Our objective was to determine the impact of patients' physical activity level on preoperative expectations and postoperative satisfaction and clinical outcomes in patients undergoing THA.

Methods: Using an institutional registry of patients undergoing THA between 2007 and 2012, we retrospectively identified patients who underwent unilateral primary THA for osteoarthritis and completed a preoperative Lower Extremity Activity Scale, Hospital for Special Surgery Hip Replacement Expectations Survey, and Hip disability and Osteoarthritis Outcome Score in addition to two-year HOOS and satisfaction evaluations. Active patients (n = 1053) were matched to inactive patients (n = 1053) by age, sex, body mass index, and comorbidities. The cohorts were compared with regard to the association of expectations with Hip disability and Osteoarthritis Outcome Score and satisfaction, the change in Lower Extremity Activity Scale level from baseline to 2 years, complications, and revision surgical procedures.

Results: Significantly more active patients (74%) expected to be "back to normal" regarding ability to exercise and participate in sports compared with inactive patients (64%, P < .001). Overall satisfaction was similar. Higher expectations with regard to exercise and sports were associated with higher HOOS sports and recreation subdomain scores in active patients. The inactive patient group improved on baseline activity level at 2 years while the active group did not.

Conclusion: At 2 years after THA, active and inactive patients were similarly satisfied and achieved comparable outcomes. Inactive patients showed a greater improvement in physical activity level from preoperative baseline than active patients. Complications and revision rates were similar.

DOI： 10.1016/j.arth.2021.03.052.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

To determine interobserver and intraobserver reliabilities of the combination of classification systems, including the Beck and acetabular labral articular disruption (ALAD) systems for transition zone cartilage, the Outerbridge system for acetabular and femoral head cartilage, and the Beck system for labral tears. Additionally, we sought to determine interobserver and intraobserver agreements in the location of injury to labrum and cartilage. Three fellowship trained surgeons reviewed 30 standardized videos of the central compartment with one surgeon re-evaluating the videos. Labral pathology, transition zone cartilage and acetabular cartilage were classified using the Beck, Beck and ALAD systems, and Outerbridge system, respectively. The location of labral tears and transition zone cartilage injury was assessed using a clock face system, and acetabular cartilage injury using a five-zone system. Intra- and interobserver reliabilities are reported as Gwet's agreement coefficients. Interobserver and intraobserver agreement on the location of acetabular cartilage lesions was highest in superior and anterior zones (0.814-0.914). Outerbridge interobserver and intraobserver agreement was >0.90 in most zones of the acetabular cartilage. Interobserver and intraobserver agreement on location of transition zone lesions was 0.844-0.944. The Beck and ALAD classifications showed similar interobserver and intraobserver agreement for transition zone cartilage injury. The Beck classification of labral tears was 0.745 and 0.562 for interobserver and intraobserver agreements, respectively. The Outerbridge classification had almost perfect interobserver and intraobserver agreement in classifying chondral injury of the true acetabular cartilage and femoral head. The Beck and ALAD classifications both showed moderate to substantial interobserver and intraobserver reliabilities for transition zone cartilage injury. The Beck system for classification of labral tears showed substantial agreement among observers and moderate intraobserver agreement. Interobserver agreement on location of labral tears was highest in the region where most tears occur and became lower at the anterior and posterior extents of this region. The available classification systems can be used for documentation regarding intra-articular pathology. However, continued development of a concise and highly reproducible classification system would improve communication.

DOI： 10.1093/jhps/hnaa064

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: Achieving a balanced knee is accepted as an important goal in total knee arthroplasty; however, the definition of ideal balance remains controversial. This study therefore endeavoured to determine: (1) whether medio-lateral gap balance in extension, midflexion, and flexion are associated with improved outcome scores at one-year post-operatively and (2) whether these relationships can be used to identify windows of optimal gap balance throughout flexion.

Methods: 135 patients were enrolled in a multicenter, multi-surgeon, prospective investigation using a robot-assisted surgical platform and posterior cruciate ligament sacrificing gap balancing technique. Joint gaps were measured under a controlled tension of 70-90 N from 10°-90° flexion. Linear correlations between joint gaps and one-year KOOS outcomes were investigated. KOOS Pain and Activities of Daily Living sub-scores were used to define clinically relevant joint gap target thresholds in extension, midflexion, and flexion. Gap thresholds were then combined to investigate the synergistic effects of satisfying multiple targets.

Results: Significant linear correlations were found throughout extension, midflexion, and flexion. Joint gap thresholds of an equally balanced or tighter medial compartment in extension, medial laxity ± 1 mm compared to the final insert thickness in midflexion, and a medio-lateral imbalance of less than 1.5 mm in flexion generated subgroups that reported significantly improved KOOS pain scores at one year (median ∆ = 8.3, 5.6 and 2.8 points, respectively). Combining any two targets resulted in further improved outcomes, with the greatest improvement observed when all three targets were satisfied (median ∆ = 11.2, p = 0.002).

Conclusion: Gap thresholds identified in this study provide clinically relevant and achievable targets for optimising soft tissue balance in posterior cruciate ligament sacrificing gap balancing total knee arthroplasty. When all three balance windows were achieved, clinically meaningful pain improvement was observed.

DOI： 10.1007/s00167-021-06482-2.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Smartphones offer the possibility of assessing recovery of mobility after total hip or knee arthroplasty (THA or TKA) passively and reliably, as well as facilitating the collection of patient-reported outcome measures (PROMs) with greater frequency. Questions/Purposes: We investigated the feasibility of using mobile technology to collect daily step data and biweekly PROMs to track recovery after total joint arthroplasty. Methods: Pre- and post-operative daily steps were recorded in prospectively enrolled patients (128 THA and 139 TKA) via an app, which uses the phone’s accelerometer. During 6-month follow-up, patients also completed PROMs (the pain numeric rating scale, the Hip Disability and Osteoarthritis Outcome Score Joint Replacement [HOOS JR] and the Knee Injury and Osteoarthritis Outcome Score Joint Replacement [KOOS JR]), and HOOS or KOOS JR quality of life domain via a mobile-enabled web link. Results: At least 6 months of follow-up was completed by 65% for THA and 68% for TKA patients. Reasons for non-completion included time commitment, phone battery, app issues, and health complications. Responses from 78% of requested PROMs were returned with 96% of patients returning at least one post-operative PROM. Step data were available from 92% of days from male patients and 86% of days from female patients. The most robust recovery occurred early, within the first 2 months. The groups with higher pre-operative steps were more likely to recover their maximum daily steps at an earlier time point. Correlations between step counts and PROMs scores were modest. Conclusion: Assessing large amounts of post-TKA and post-THA step data using mobile technology is feasible. Completion rates were good, making the technology very useful for collecting frequent PROMs. Being unable to ensure that patients always carried their phones limited our analysis of the step counts.

DOI： 10.1007/s11420-019-09746-3

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Bone stress injuries (BSIs) are common among runners for which activity modification is the primary treatment. The clinical utility of measuring activity during recovery has not been evaluated.

Questions/purposes: We sought to measure the physical activity of runners recovering from BSIs and determine if activity can be correlated with symptoms.

Methods: A prospective observational pilot study was performed of runners with a new lower extremity BSI treated non-surgically. For 30 days, activity of runners was measured with a physical activity tracker and daily pain scores were collected.

Results: We enrolled 18 runners (average age, 33 years; 72% female). Twelve had stress fractures and six had stress reactions. The average daily steps of all runners during the observation period was 10,018 ± 3232, and the runner with the highest daily steps averaged 15,976. There were similar average daily steps in those with stress fractures versus reactions, 10,329 versus 9965, respectively. There was no correlation between daily steps or relative change in daily steps with pain or relative change in pain scores.

Conclusion: Runners with BSIs averaged over 10,000 steps per day during early recovery. Clinicians may not be aware of the amount of activity runners maintain after being diagnosed with a BSI. Although daily steps and symptoms could not be correlated in this study, objectively measuring activity may assist clinicians in guiding runners recovering from BSIs.

DOI： 10.1007/s11420-020-09787-z.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The primary objective of this study was to determine the incidence of symptomatic venous thromboembolism (VTE), including pulmonary embolism (PE) and deep vein thrombosis (DVT), in the hip fracture population. Secondary objectives included determining timing of VTE diagnosis, VTE thromboprophylaxis given, and identifying any factors associated with VTE.

Methods: Using data from the FAITH and HEALTH trials, the incidence of VTE, including DVT and PE, and the timing of VTE were determined. A multivariable Cox regression analysis was used to determine which factors were associated with increased risk of VTE, including age, treatment for comorbidity, thromboprophylaxis, time to surgery, and method of fracture management.

Results: 2520 hip fracture patients were included in the analysis. Sixty-four patients (2.5%) had a VTE [DVT: 36 (1.4%), PE: 28 (1.1%)]. Thirty-five (54.7%) were diagnosed less than 6 weeks postfracture and 29 (45.3%) more than 6 weeks postfracture. One thousand nine hundred ninety-three (79%) patients received thromboprophylaxis preoperatively and 2502 (99%) received thromboprophylaxis postoperatively. The most common method of preoperative (46%) and postoperative (73%) thromboprophylaxis was low molecular weight heparin. Treatment with arthroplasty compared to internal fixation was the only variable associated with increased risk of VTE (hazard ratio 2.67, P = 0.02).

Conclusions: The incidence of symptomatic VTE in hip fracture patients recruited to the 2 trials was 2.5%. Although over half of the cases were diagnosed within 6 weeks of fracture, VTE is still prevalent after this period. The majority of patients received thromboprophylaxis. Treatment with arthroplasty rather than fixation was associated with increased incidence of VTE.

DOI： 10.1097/BOT.0000000000001939.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The Knee Injury Osteoarthritis Outcome Survey, Joint Replacement (KOOS, JR) is a reliable, responsive, and validated patient-reported outcome measure (PROM) of knee health in patients with knee osteoarthritis undergoing unilateral primary total knee arthroplasty (TKA). The validity of the KOOS, JR for revision TKA remains unknown.

Methods: We identified 314 patients who underwent revision TKA and had completed preoperative and 2-year postoperative PROMs. Validation included assessment of local dependence, unidimensionality, internal consistency, external construct validity, responsiveness, and floor effects preoperatively and ceiling effects at 2 years postoperatively.

Results: Among patients undergoing revision TKA, the KOOS, JR demonstrated an absence of residual item correlation, adequate unidimensionality, high internal consistency (Person Separation Index: 0.897), and high external construct validity with existing validated PROMs, including KOOS Pain (Spearman's correlation coefficient 0.89) and KOOS activities of daily living (0.90) domains. The KOOS, JR was more responsive (standardized response means: 1.14) to revision TKA than other common knee PROMs. Three percent of revision TKA patients were at the floor (lowest score) preoperatively and 9% reached the ceiling (highest possible score) postoperatively.

Conclusions: KOOS, JR performs well in revision TKA patients with regard to internal consistency, external validity, responsiveness, and floor and ceiling effects. Our results support extending its use to revision TKA in both clinical and research settings.

DOI： 10.1016/j.arth.2020.04.016.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Total hip replacement (THR)/total knee replacement (TKR) studies do not uniformly measure patient centered domains, pain, and function. We aim to validate existing measures of pain and function within subscales of standard instruments to facilitate measurement. Methods: We evaluated baseline and 2-year pain and function for THR and TKR using Hip disability and Osteoarthritis Outcome Score (HOOS)/Knee Injury and Osteoarthritis Outcome Score (KOOS), with primary unilateral TKR (4796) and THR (4801). Construct validity was assessed by correlating HOOS/KOOS pain and activities of daily living (ADL), function quality of life (QOL), and satisfaction using Spearman correlation coefficients. Patient relevant thresholds for change in pain and function were anchored to improvement in QOL; minimally clinically important difference (MCID) corresponded to “a little improvement” and a really important difference (RID) to a “moderate improvement.” Pain and ADL function scores were compared by quartiles using Kruskal-Wallis. Results: Two-year HOOS/KOOS pain and ADL function correlated with health-related QOL (KOOS pain and Short Form 12 Physical Component Scale ρ = 0.54; function ρ = 0.63). Comparing QOL by pain and function quartiles, the highest levels of pain relief and function were associated with the most improved QOL. MCID for pain was estimated at ≥20, and the RID ≥29; MCID for function ≥14, and the RID ≥23. The measures were responsive to change with large effect sizes (≥1.8). Conclusion: We confirm that HOOS/KOOS pain and ADL function subscales are valid measures of critical patient centered domains after THR/TKR, and achievable thresholds anchored to improved QOL. Cost-free availability and brevity makes them feasible, to be used in a core measurement set in total joint replacement trials.

DOI： 10.1016/j.arth.2019.12.038

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1177/0363546519895242

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Patient satisfaction after total hip (THA) and total knee arthroplasty (TKA) is a core outcome selected by the Outcomes Measurement in Rheumatology. Up to 20% of THA/TKA patients are dissatisfied. Improving patient satisfaction is hindered by the lack of a validated measurement tool that can accurately measure change. Methods: The psychometric properties of a proposed satisfaction instrument, consisting of 4 questions rated on a Likert scale, scored 1-100, were tested for validity, reliability, and sensitivity to change using data collected between 2007 and 2011 in an arthroplasty registry. Results: We demonstrated construct validity by confirming our hypothesis; satisfaction correlated with similar constructs. Satisfaction correlated moderately with pain relief (TKA ρ = 0.61, THA ρ = 0.47) and function (TKA ρ = 0.65, THA ρ = 0.51) at 2 years; there was no correlation with baseline/preoperative pain/function values, as expected. Overall Cronbach's alpha >0.88 confirmed internal consistency. Test-retest reliability with weighted kappa ranged 0.60-0.75 for TKA and 0.36-0.56 for THA. Hip disability and Osteoarthritis Outcome Score/Knee injury and Osteoarthritis Outcome Scores quality of life improvement (>30 points) corresponds to a mean satisfaction score of 93.2 (standard deviation, 11.5) after THA and 90.4 (standard deviation, 13.8) after TKA, and increasing relief of pain and functional improvement increased the strength of their association with satisfaction. The satisfaction measure has no copyright and is available free of cost and represents minimal responder burden. Conclusion: Patient satisfaction with THA/TKA can be measured with a validated 4-item questionnaire. This satisfaction measure can be included in a total joint arthroplasty core measurement set for total joint arthroplasty trials.

DOI： 10.1016/j.arth.2020.02.039

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The Knee Injury Osteoarthritis Outcome Survey, Joint Replacement (KOOS, JR) is a reliable, responsive, and validated patient-reported outcome measure (PROM) of knee health in patients with knee osteoarthritis undergoing unilateral primary total knee arthroplasty (TKA). The validity of the KOOS, JR for revision TKA remains unknown. Methods: We identified 314 patients who underwent revision TKA and had completed preoperative and 2-year postoperative PROMs. Validation included assessment of local dependence, unidimensionality, internal consistency, external construct validity, responsiveness, and floor effects preoperatively and ceiling effects at 2 years postoperatively. Results: Among patients undergoing revision TKA, the KOOS, JR demonstrated an absence of residual item correlation, adequate unidimensionality, high internal consistency (Person Separation Index: 0.897), and high external construct validity with existing validated PROMs, including KOOS Pain (Spearman's correlation coefficient 0.89) and KOOS activities of daily living (0.90) domains. The KOOS, JR was more responsive (standardized response means: 1.14) to revision TKA than other common knee PROMs. Three percent of revision TKA patients were at the floor (lowest score) preoperatively and 9% reached the ceiling (highest possible score) postoperatively. Conclusions: KOOS, JR performs well in revision TKA patients with regard to internal consistency, external validity, responsiveness, and floor and ceiling effects. Our results support extending its use to revision TKA in both clinical and research settings.

DOI： 10.1016/j.arth.2020.04.016

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Although p values are standard for reporting statistical significance of patient-reported outcome measures (PROMs), the shift toward clinically important outcome values, including minimal clinically important difference (MCID) and substantial clinical benefit (SCB), necessitates re-evaluation of the current literature. Questions/Purposes: We sought to answer two questions regarding studies on primary hip arthroscopy performed for the treatment of femoroacetabular impingement syndrome (FAIS). (1) Do such studies reporting statistical significance on common PROMs meet published MCID/SCB thresholds? (2) What proportion of such studies report both statistical and clinical significance? Methods: We identified four papers published in two journals defining MCID/SCB values on the modified Harris Hip Score (mHHS), Hip Outcome Score–Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sport (HOS-Sport), international Hip Outcome Tool (iHOT-33), and its short version (iHOT-12) for different groups of FAIS patients undergoing hip arthroscopy. We reviewed these two journals from the dates of publication to the present to identify papers reporting changes in post-operative PROMs. The difference in pre- and post-operative scores on each PROM was calculated and compared to MCID/SCB thresholds. Results: Twelve studies were included. Ten studies (83%) evaluated mHHS (90% met MCID, 50% met SCB), seven (58%) evaluated HOS-ADL (100% met MCID/SCB) and HOS-Sport (100% met MCID, 57% met SCB), and one (8%) evaluated iHOT-33 (met MCID/SCB) and iHOT-12 (met MCID). Most studies met MCID and SCB at both 1- and 2-year timepoints. Of the studies evaluated, 50% reported clinical relevance. Conclusions: Nearly all studies evaluated met MCID, while fewer met SCB. Only half discussed these clinical measures. It is proposed that all future studies report both statistical and clinical significance as standard best practice.

DOI： 10.1007/s11420-020-09759-3

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objectives We developed and validated an electronically administered patient-specific visual analogue survey (PVS) to evaluate changes in hand function after treatment with injectable collagenase clostridium histolyticum (CCH) in Dupuytren's contracture. The items in the PVS were authored and ranked in importance by the patients. Methods In an open-label trial for patients with Dupuytren's contracture receiving CCH injection, 109 patients completed the PVS on the day of injection, day of manipulation and 30-day follow-up. For external validation, patients also completed standard patient-reported outcome measures, the Overall Treatment Effects Scale and QuickDASH, and underwent physician assessment of contracture via goniometry and the table top test. Results Responses were highly individualised with no single activity being chosen as important by more than 8% of patients. Sports-related activities were mentioned most often (23%). The PVS was highly responsive to changes in patients' conditions with CCH injection (effect size=1.49), much more so than the QuickDASH (effect size=0.50). Additionally, the PVS had no floor or ceiling effects, whereas the QuickDASH ceiling approached 20% post-injection. The PVS had excellent internal consistency (Cronbach's α=0.95) and correlated strongly with the QuickDASH post-injection (Spearman's=-0.67). PVS scores were significantly higher for patients reporting their condition had improved versus those reporting no change after injection. The test-retest reliability of the PVS was poor to fair, in part due to allowing patients to choose different activities at test and retest. However, test-retest reliability was good (intraclass correlation coefficient >0.7) and better than QuickDASH among patients who rated the same activities at test and retest. Conclusions The PVS is simple to administer and enables individualised assessment in a large number of patients. It is also readily adaptable for use in other diseases, particularly within musculoskeletal medicine. Level of evidence Therapeutic II: Prospective cohort.

DOI： 10.1136/jisakos-2019-000301

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: Medial release during total knee arthroplasty (TKA) is used to correct ligament imbalance in knees with varus deformity. However, questions remain on whether residual ligament imbalance would be related to inferior clinical results. The purposes of the present study were to measure the intraoperative joint gap and to evaluate the effect of intraoperative soft tissue condition on the new Knee Society Score (KSS 2011) at 2-year follow-up, without the maneuver of additional medial release to correct the asymmetrical gap balance. Methods: Varus–valgus gap angle and joint gap were measured using a tensor device without medial release for 100 knees with preoperative varus deformity. The knees were categorized according to the varus–valgus gap angle and the laxity. The preoperative and postoperative clinical outcomes using KSS 2011 were compared between the groups. Results: The average varus–valgus angles had a residual imbalance of 2.8° varus and 1.3° varus in extension and flexion, respectively. In comparison, according to varus–valgus joint gap angle and knee laxity in extension and flexion, no significant differences were found in postoperative range of motion and subscale of KSS 2011 among the groups. Conclusion: Intraoperative asymmetrical joint gap and physiological laxity do not affect early clinical results after TKA. Level of evidence: III.

DOI： 10.1007/s00167-020-05862-4

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The effect of an anterior condylar height (ACH) change after total knee arthroplasty (TKA) is not well-known. The effect of an ACH change was evaluated on postoperative knee flexion, New Knee Society Scores (2011KSS), and patellofemoral contact force. Methods: The study included 101 knees that underwent TKA. The medial or lateral ACH was measured using pre-operative and postoperative computed tomography. Pearson correlation between the change in ACH and knee flexion was calculated. The determinant of the change in flexion was evaluated using multivariable linear regression. The association between ACH and 2011KSS was assessed. Using the cases with the three highest and three lowest pre-operative medial ACHs, computer simulation was performed to detect the changes in patellofemoral contact forces. Results: A postoperative reduction in ACH correlated with increased flexion at one year (medial ACH, R = 0.58; lateral ACH, R = 0.48). On multivariable linear regression, reductions in medial ACH (β = 1.7, P < 0.001) and pre-operative flexion (β = − 0.3, P < 0.001) were associated with increased flexion. A decrease in ACH was associated with improvements in advanced activities (medial, R² = 0.06; lateral, R² = 0.08) in 2011KSS. On computer simulation, all three cases with reduced and increased medial ACHs showed decreased and increased patellofemoral contact forces, respectively. Conclusions: A change in ACH was an independent predictor of knee flexion after TKA. Greater reduction in ACH was associated with improved flexion after TKA, whereas an increase in postoperative ACH may be a risk factor for flexion loss.

DOI： 10.1016/j.knee.2019.09.002

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective: To determine whether racial disparities in total knee replacement (TKR) failure are explained by poverty. Methods: Black and white New York state residents, enrolled in a prospective single-institution TKR registry January 1, 2008 to February 6, 2012, who underwent primary unilateral TKR (n = 4,062) were linked to the New York Statewide Planning and Research Cooperative System database (January 1, 2008 to December 31, 2014) to capture revisions performed at outside institutions. Patients were linked by geocoded addresses to residential census tracts. Multivariable Cox regression was used to assess predictors of TKR revision. Multivariable logistic regression was used to analyze predictors of TKR failure, defined as TKR revision in New York state ≤2 years after surgery, or as Hospital for Special Surgery (HSS) TKR quality of life score “not improved” or “worsened” 2 years after surgery. Results: The mean ± SD age was 68.4 ± 10 years, 64% of patients were female, 8% lived in census tracts with >20% of the population under the poverty line, and 9% were black. Median follow-up time was 5.3 years. A total of 3% of patients (122 of 4,062) required revision a median 454 days (interquartile range 215–829) after surgery. TKR revision risk was higher in blacks than whites, with a hazard ratio of 1.69 (95% confidence interval 1.01–2.81), but in multivariable analysis, only younger age, male sex, and constrained prosthesis were predictors of TKR revision. TKR failure occurred in 200 of 2,832 cases (7%) with 2-year surveys. Risk factors for TKR failure were non-osteoarthritis TKR indication, low surgeon volume, and low HSS Expectations Survey score, but not black race. Community poverty was not associated with TKR revision or failure. Conclusion: There was a trend toward higher TKR revision risk in blacks, but poverty did not modify the relationship between race and TKR revision or failure.

DOI： 10.1002/acr.24028

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Only a few studies have described the effect of diffuse idiopathic skeletal hyperostosis (DISH) on the clinical results after lumbar surgery. The aim of the study is to clarify the associations between DISH and the clinical results after lumbar decompression surgery. Methods: The outcomes of 328 consecutive patients who underwent primary lumbar decompression surgery for treatment of lumbar canal stenosis with or without grade I spondylolisthesis were analysed retrospectively. The major outcome measures were surgery-free survival and the need for further surgery because of same-segment disease (SSD) and/or adjacent-segment disease (ASD). Results: Of the 328 patients, 69 (60 men and nine women) were diagnosed with DISH. The Japanese Orthopaedic Association score before and at 1 year after the surgery did not differ significantly between patients with and without DISH. However, the rate of revision surgery in the follow-up period was significantly higher in patients with DISH than in those without (19% vs 6.9%, p = 0.0050). Cox proportional-hazards modelling revealed that DISH and sex (female) were independent risk factors for the need for revision surgery after decompression surgery for degenerative lumbar spine. The rate of revision surgery was higher in the sub-group of DISH with ossification extended to L2 or more than that for those with the ossification extended to L1 (26% vs 8%, p = 0.11), but the difference did not reach statistical significance. Conclusions: DISH is a risk factor for revision surgery after decompression surgery for degenerative lumbar spine because of SSD and/or ASD.

DOI： 10.1016/j.jos.2019.09.003

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: We hypothesized that patients undergoing primary total knee arthroplasty (TKA) for rheumatoid arthritis (RA) would have different preoperative expectations compared to osteoarthritis (OA) patients, and that postoperative satisfaction would correlate with specific postoperative pain and functional domains. Methods: This is a retrospective cohort study of RA patients matched based on age, gender, American Society of Anesthesiologists score, and Charlson Comorbidity Index score 1:2 with OA patients (76 RA, 152 OA) who underwent primary TKA. The Hospital for Special Surgery Knee Replacement Expectations Survey, Visual Analogue Scale for Pain (VAS), Knee injury and Osteoarthritis Outcome Score (KOOS), and the Short Form-12 (SF-12) were compared at baseline and at 2 years postoperatively. Minimum clinically important differences (MCIDs) were calculated for KOOS and SF-12 subdomains. Results: Preoperatively, RA patients had lower expectations, worse VAS Pain, and worse KOOS Pain, Symptoms, and Activities of Daily Living (P <.05). However, at 2 years, RA patients had significantly larger improvements in VAS (P =.01) and these 3 KOOS subdomains (P <.05), achieving comparable absolute scores to OA patients. Overall, 86.1% of RA and 87.1% of OA patients were either somewhat or very satisfied with their TKA. Patient satisfaction correlated with VAS Pain and KOOS outcome scores in both groups. RA and OA patients had high rates of achieving MCID in SF-12 physical component scores and all 5 KOOS subdomains. A higher proportion of RA patients achieved MCID in KOOS Symptoms (98.4% vs 77.2%, P <.001). Conclusion: RA patients had lower baseline expectations compared to OA patients. However, RA patients had greater improvements in KOOS and SF-12 subdomains, and there was no difference in satisfaction compared to OA patients after TKA.

DOI： 10.1016/j.arth.2019.04.034

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Intra-articular injection of adipose-derived stem cells (ASCs) has shown promise for improving symptoms and cartilage quality in the treatment of osteoarthritis (OA). However, while most preclinical studies have been performed with plastic-adherent ASCs, most clinical trials are being conducted with the stromal vascular fraction (SVF), prepared from adipose tissue without prior culture. Purpose: To directly compare clinical outcomes of intra-articular injection with ASCs or SVF in patients with knee OA. Study Design: Cohort study; Level of evidence, 3. Methods: The authors retrospectively compared 6-month outcomes in 42 patients (59 knees) receiving intra-articular injection with 12.75 million ASCs and 38 patients (69 knees) receiving a 5-mL preparation of SVF. All patients had Kellgren-Lawrence grade 2, 3, or 4 knee OA and had failed standard medical therapy. The visual analog scale (VAS) pain score and Knee injury and Osteoarthritis Outcome Score (KOOS) at baseline and 1, 3, and 6 months after injection were considered as outcomes. Outcome Measures in Rheumatology–Osteoarthritis Research Society International (OMERACT-OARSI) criteria were also used to assess positive response. A repeated measures analysis of variance was used for comparison between the treatment groups. Results: No major complications occurred in either group. The SVF group had a higher frequency of knee effusion (SVF 8%, ASC 2%) and minor complications related to the fat harvest site (SVF 34%, ASC 5%). Both groups reported improvements in pain VAS and KOOS domains. Specifically, in the ASC group, symptoms improved earlier (by 3 months; P <.05) and pain VAS decreased to a greater degree (55%; P <.05) compared with the SVF group (44%). The proportion of OMERACT-OARSI responders in the ASC group was slightly higher (ASCs, 61%; SVF, 55%; P =.25). Conclusion: It was observed that both ASCs and SVF resulted in clinical improvement in patients with knee OA, but that ASCs outperform SVF in the early reduction of symptoms and pain with less comorbidity.

DOI： 10.1177/0363546519864359

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Study Design.Retrospective database analysis.Objective.To identify preoperative risk factors for emergency department (ED) visit and unplanned hospital readmission after primary anterior cervical discectomy and fusion (ACDF) at 30 and 90 days.Summary of Background Data.Limited data exist to identify factors associated with ED visit or readmission after primary ACDF within the first 3 months following surgery.Methods.Patients undergoing ACDF from 2005 to 2012 were identified in the Statewide Planning and Research Cooperative System database. Multivariable regression models were created based on patient-level and surgical characteristics to identify independent risk factors for hospital revisit.Results.Of 41,813 patients identified, 2514 (6.0%) returned to the ED within 30 days of discharge. Risk factors included age < 35, black race (OR 1.19), Charlson Comorbidity index score > 1, length of stay (LOS) greater than 1 day (OR 1.23), and fusion of > 2 levels (OR 1.17). Four thousand six hundred nine (11.0%) patients returned to the ED within 90 days. Risk factors mirrored those at 30 days. Patients having private insurance or those discharged to rehab were less likely to present to the ED. One thousand three hundred ninety-four (3.3%) patients were readmitted by 30 days. Risk factors included male sex, Medicare, or Medicaid insurance (OR 1.71 and 1.79 respectively), Charlson comorbidity index > 1, discharge to a skilled nursing facility (OR 2.90), infectious/pathologic (OR 3.296), or traumatic (OR 1.409) surgical indication, LOS > 1 day (OR 1.66), or in-hospital complication. 2223 (5.3%) patients were readmitted by 90 days. Risk factors mirrored those at 30 days. No differences in readmission were seen based on race or number of levels fused. Patients aged 18 to 34 were less likely to be readmitted versus patients older than 35.Conclusion.Insurance status, comorbidities, and LOS consistently predicted an unplanned hospital visit at 30 and 90 days. Although nondegenerative surgical indications and in-hospital complications did not predict ED visits, these factors increased the risk for readmission.Level of Evidence: 3.

DOI： 10.1097/BRS.0000000000003058

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Dynamic tibial tray sensors are playing an increasing role in total knee arthroplasty (TKA) coronal balancing. Sensor balance is proposed to lead to improved patient outcomes compared with sensor-unbalanced TKA, and traditional manual-balanced TKA. However, the “learning curve” of this technology is not known, and also whether sensor use can improve manual TKA balance skills once the sensor is taken away, effectively “training” the surgeon. Methods: We conducted a single-surgeon prospective study on 104 consecutive TKAs. In Nonblinded Phase I (n = 49), sensor-directed releases were performed during trialing and final intercompartmental load was recorded. In Blinded Phase II (n = 55), manual-balanced TKA was performed and final sensor readings were recorded by a blinded observer after cementation. We used cumulative summation analysis and sequential probability ratio testing to analyze the surgeon learning curve in both phases. Results: In Nonblinded Phase I, sensor balance proficiency was attained most easily at 10°, followed by 90°, and most difficult to attain at 45° of flexion. In Blinded Phase II, manual balance was lost most quickly at 45°, followed by 90°, and preserved for longest at 10° of flexion. The number of cases in the steady state periods (early phase periods where there is a mix of sensor balance and sensor imbalance) for both phases is similar. Conclusions: A surgeon who consistently uses the dynamic sensor demonstrates a learning curve with its use, and an “attrition” curve once it is removed. Consistent sensor balance is more predictable with constant sensor use.

DOI： 10.1016/j.artd.2019.03.001

記述言語：英語   掲載種別：研究論文（学術雑誌）  

□Total joint arthroplasty is performed to decreased pain, restore function and productivity and improve quality of life. □One-year implant survivorship following surgery is nearly 100%; however, self-reported satisfaction is 80% after total knee arthroplasty and 90% after total hip arthroplasty. □ Patient-reported outcomes (PROs) are produced by patients reporting on their own health status directly without interpretation from a surgeon or other medical professional; a PRO measure (PROM) is a tool, often a questionnaire, that measures different aspects of patientrelated outcomes. □ Generic PROs are related to a patient's general health and quality of life, whereas a specific PRO is focused on a particular disease, symptom or anatomical region. □ While revision surgery is the traditional endpoint of registries, it is blunt and likely insufficient as a measure of success; PROMs address this shortcoming by expanding beyond survival and measuring outcomes that are relevant to patients - relief of pain, restoration of function and improvement in quality of life. □ PROMs are increasing in use in many national and regional orthopaedic arthroplasty registries. □PROMs data can provide important information on valuebased care, support quality assurance and improvement initiatives, help refine surgical indications and may improve shared decision-making and surgical timing. □There are several practical considerations that need to be considered when implementing PROMs collection, as the undertaking itself may be expensive, a burden to the patient, as well as being time and labour intensive.

DOI： 10.1302/2058-5241.4.180080

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BackgroundIdentifying patients at risk of not achieving meaningful gains in long-term postsurgical patient-reported outcome measures (PROMs) is important for improving patient monitoring and facilitating presurgical decision support. Machine learning may help automatically select and weigh many predictors to create models that maximize predictive power. However, these techniques are underused among studies of total joint arthroplasty (TJA) patients, particularly those exploring changes in postsurgical PROMs.Question/purposes(1) To evaluate whether machine learning algorithms, applied to hospital registry data, could predict patients who would not achieve a minimally clinically important difference (MCID) in four PROMs 2 years after TJA; (2) to explore how predictive ability changes as more information is included in modeling; and (3) to identify which variables drive the predictive power of these models.MethodsData from a single, high-volume institution's TJA registry were used for this study. We identified 7239 hip and 6480 knee TJAs between 2007 and 2012, which, for at least one PROM, patients had completed both baseline and 2-year followup surveys (among 19,187 TJAs in our registry and 43,313 total TJAs). In all, 12,203 registry TJAs had valid SF-36 physical component scores (PCS) and mental component scores (MCS) at baseline and 2 years; 7085 and 6205 had valid Hip and Knee Disability and Osteoarthritis Outcome Scores for joint replacement (HOOS JR and KOOS JR scores), respectively. Supervised machine learning refers to a class of algorithms that links a mapping of inputs to an output based on many input-output examples. We trained three of the most popular such algorithms (logistic least absolute shrinkage and selection operator (LASSO), random forest, and linear support vector machine) to predict 2-year postsurgical MCIDs. We incrementally considered predictors available at four time points: (1) before the decision to have surgery, (2) before surgery, (3) before discharge, and (4) immediately after discharge. We evaluated the performance of each model using area under the receiver operating characteristic (AUROC) statistics on a validation sample composed of a random 20% subsample of TJAs excluded from modeling. We also considered abbreviated models that only used baseline PROMs and procedure as predictors (to isolate their predictive power). We further directly evaluated which variables were ranked by each model as most predictive of 2-year MCIDs.ResultsThe three machine learning algorithms performed in the poor-to-good range for predicting 2-year MCIDs, with AUROCs ranging from 0.60 to 0.89. They performed virtually identically for a given PROM and time point. AUROCs for the logistic LASSO models for predicting SF-36 PCS 2-year MCIDs at the four time points were: 0.69, 0.78, 0.78, and 0.78, respectively; for SF-36 MCS 2-year MCIDs, AUROCs were: 0.63, 0.89, 0.89, and 0.88; for HOOS JR 2-year MCIDs: 0.67, 0.78, 0.77, and 0.77; for KOOS JR 2-year MCIDs: 0.61, 0.75, 0.75, and 0.75. Before-surgery models performed in the fair-to-good range and consistently ranked the associated baseline PROM as among the most important predictors. Abbreviated LASSO models performed worse than the full before-surgery models, though they retained much of the predictive power of the full before-surgery models.ConclusionsMachine learning has the potential to improve clinical decision-making and patient care by helping to prioritize resources for postsurgical monitoring and informing presurgical discussions of likely outcomes of TJA. Applied to presurgical registry data, such models can predict, with fair-to-good ability, 2-year postsurgical MCIDs. Although we report all parameters of our best-performing models, they cannot simply be applied off-the-shelf without proper testing. Our analyses indicate that machine learning holds much promise for predicting orthopaedic outcomes.

DOI： 10.1097/CORR.0000000000000687

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Introduction: The Knee Injury and Osteoarthritis Outcomes Survey (KOOS) has been translated into 50 languages worldwide. These translations have adhered to guidelines for cross cultural adaptation of health surveys. However, after release of the Japanese KOOS (JKOOS) we discovered the JKOOS was not fully culturally relevant to Japanese patients. Therefore, we undertook the development and validation of the JKOOS+. Methods: We completed this project in 2 phases across 9 hospitals. In Phase 1, 187 surgically naïve patients with knee pain were asked about activities limited by their knee pain. An expert panel reconciled these activities against existing KOOS items to identify novel items. In Phase 2, 241 surgically naïve patients with knee pain were administered the Japanese Oxford Knee Survey, JKOOS, and these novel items. An iterative Rasch analysis was used to test item fit of these novel items within the KOOS Activities of Daily Living (ADL) domain and a potential new domain. Unidimensionality was assessed using principle component analysis. Internal consistency (Cronbach's alpha) and external validity (Spearman's Correlations) were assessed for Japanese ADL (J-ADL) and the novel domain. Results: Phase 1 identified 4 activities relevant to Japanese knee patients: sitting seiza, using a Japanese toilet, climbing hills, and getting on/off a bus/train. In Phase 2, climbing hills and bus/train were well fit in JADL. Seiza and using a Japanese toilet were not well fit in J-ADL, yet both require deep knee flexion so a knee flexion (KF) domain was constructed by considering all KOOS items that require knee flexion using an iterative Rasch model. An 8 item KF domain emerged. Both J-ADL and KF were deemed to be unidimensional with high internal consistency (Cronbach's alpha >0.92) and external validity (Spearman Correlations 0.723–0.929). Conclusions: We have successfully developed and validated JKOOS+, a more culturally relevant knee survey for Japanese patients.

DOI： 10.1016/j.jos.2018.11.014

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Patient-reported outcome measures (PROMs) are being used increasingly to determine the success of total knee arthroplasty (TKA). Our goal is to investigate whether advanced age is associated with lower PROM scores. Methods: We used our hospital's TKA registry to examine the relationship between age and PROMs in all patients 50-90 years of age who underwent unilateral or simultaneous bilateral primary TKA between 2007 and 2011 with a primary diagnosis of osteoarthritis. All 5 domains of the Knee Injury and Arthritis Outcomes Score (KOOS) and the Lower Extremity Activity Scale (LEAS) at baseline, 2 years, and 5 years were collected. The association between age and PROM score was assessed by piecewise linear regression using generalized estimating equations, adjusting for demographics, comorbidity, and baseline score. Results: Significant nonlinear relationships among age, KOOS subdomains, and LEAS were found. The placement of the age spline knot was at 70 years for KOOS Symptom and 68 years for KOOS Pain, KOOS Activities of Daily Living (ADL), and LEAS. The KOOS Symptom domain showed a significant worsening between 2-year and 5-year follow-up (P <.05) as patients got older. Conclusion: We found an age-related decline in KOOS Pain, KOOS Symptom, KOOS ADL, and LEAS scores. The best fitting spline knots were at 68 (KOOS Pain, KOOS ADL, and LEAS) and 70 years (KOOS Symptoms), respectively. This demonstrates that there is a critical age at which functional decline begins regardless of the quality of the TKA surgery. Our findings will help surgeons accurately guide patient expectations after TKA based on age. Level of Evidence: Level II, prognostic study.

DOI： 10.1016/j.arth.2018.09.046

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Patient-reported outcome measures (PROMs) help assess therapeutic effectiveness. This study assessed the effect of advanced age on the Hip Disability and Osteoarthritis Outcome Score (HOOS) and Lower Extremity Activity Scale (LEAS) after total hip arthroplasty (THA). Methods: A prospective cohort of patients underwent primary THA at our institution between May 2007 and December 2011. Exposure was age at the time of surgery and outcomes were HOOS and LEAS scores 2 and 5 years postsurgery. We used a multivariable longitudinal generalized estimating equation to elucidate the effect of age on PROM scores. Results: Our analysis of 3700 THA patients (mean age, 66 years; 56.4% female) demonstrated a decline in scores by age for the LEAS, HOOS Activities of Daily Living, and HOOS Sport and Recreation domains. There was also association between age and HOOS Symptoms and HOOS Quality of Life domains, but not between age and the HOOS Pain domain. Critical ages at which the relationship between age and outcome changed was 63 years for the HOOS Pain, Symptom, Activities of Daily Living, and Quality of Life domains, and 72 years for the HOOS Sport and Recreation domain and the LEAS. Conclusion: Patients undergoing THA at older ages reported lower activity and sports and recreation scores than younger patients, but similar pain, symptoms, and quality of life scores. This knowledge can help physicians guide patients’ expectations before THA. Our findings also indicate that PROM scores should be age adjusted when used for quality or value comparisons between hospitals or physicians.

DOI： 10.1016/j.arth.2019.02.023

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Introduction: Trunnion geometry is known to vary between hip systems. Trunnionosis and the impact of trunnion design on total hip arthroplasty (THA) survival, has gained attention as a failure mechanism. We sought to report the differences in patient-reported outcome measures (PROMs) between the most commonly utilised modern THA trunnions. Methods: We reviewed primary unilateral THA patients from May 2007 to October 2011. The most frequently used stems were included. LEAS, HOOS subdomains, and SF-12 were obtained pre and post operatively while satisfaction was measured at 2 years after THA. Trunnions were grouped by taper geometry and manufacturer. The 2-year change in PROMs for each trunnion was compared to the pooled 2-year change in HOOS for all other trunnions. Results: 3950 THA patients were studied. 6 trunnion designs were evaluated from 5 manufacturers. The range in differences between the 2-year change in individual PROMs were as follows: HOOS pain (0.6–2.4), HOOS symptoms (0–3.8), HOOS ADL (0.4–4), and HOOS QOL (0.5–3.6). None of the differences in the 2-year change in PROMs reached a minimal clinically important change (MCIC), which we previously determined to be a minimum of 9 points for all HOOS domains. Conclusion: All of the trunnions designs utilised in our study cohort demonstrated excellent clinical results. Small differences were well below the known MCIC; and were not clinically relevant. The findings of this study should prompt further investigations into the long-term impact of trunnion design on clinical patient-reported outcomes.

DOI： 10.1177/1120700019864317

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Aims The outcomes of total knee arthroplasty (TKA) depend on many factors. The impact of implant design on patient-reported outcomes is unknown. Our goal was to evaluate the patient-reported outcomes and satisfaction after primary TKA in patients with osteoarthritis undergoing primary TKA using five different brands of posterior-stabilized implant. Patients and Methods Using our institutional registry, we identified 4135 patients who underwent TKA using one of the five most common brands of implant. These included Biomet Vanguard (Zimmer Biomet, Warsaw, Indiana) in 211 patients, DePuy/Johnson & Johnson Sigma (DePuy Synthes, Raynham, Massachusetts) in 222, Exactech Optetrak Logic (Exactech, Gainesville, Florida) in 1508, Smith & Nephew Genesis II (Smith & Nephew, London, United Kingdom) in 1415, and Zimmer NexGen (Zimmer Biomet) in 779 patients. Patients were evaluated preoperatively using the Knee Injury and Osteoarthritis Outcome Score (KOOS), Lower Extremity Activity Scale (LEAS), and 12-Item Short-Form Health Survey questionnaire (SF-12). Demographics including age, body mass index, Charlson Comorbidity Index, American Society of Anethesiologists status, sex, and smoking status were collected. Postoperatively, two-year KOOS, LEAS, SF-12, and satisfaction scores were compared between groups. Results Outcomes were available for 4069 patients (98%) at two years postoperatively. In multiple regression analysis, which separately compared each implant group with the aggregate of all others, there were no clinically significant differences in the change of KOOS score from baseline to two-year follow-up between any of the groups. More than 80% of patients in each group were satisfied at this time in all domains. In a multivariate regression model, patients in the NexGen group were the most likely to be satisfied (odds ratio (OR) 1.63; p = 0.006) and Optetrak Logic patients were the least likely to be satisfied (OR 0.60; p < 0.001). Conclusion TKA provides improvement in function and satisfaction regardless of the type of implant. We could not demonstrate superiority of one design above others across these groups of implants, and any price premium for one above the other systems may not be justified. Healthcare administrators may find these similarities in outcomes helpful when negotiating purchasing contracts.

DOI： 10.1302/0301-620X.101B7.BJJ-2018-1382.R1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Aims Custom flange acetabular components (CFACs) are a patient-specific option for addressing large acetabular defects at revision total hip arthroplasty (THA), but patient and implant characteristics that affect survivorship remain unknown. This study aimed to identify patient and design factors related to survivorship. Patients and Methods A retrospective review of 91 patients who underwent revision THA using 96 CFACs was undertaken, comparing features between radiologically failed and successful cases. Patient characteristics (demographic, clinical, and radiological) and implant features (design characteristics and intraoperative features) were collected. There were 74 women and 22 men; their mean age was 62 years (31 to 85). The mean follow-up was 24.9 months (sd 27.6; 0 to 116). Two sets of statistical analyses were performed: 1) univariate analyses (Pearson’s chi-squared and independent-samples Student’s t-tests) for each feature; and 2) bivariable logistic regressions using features identified from a random forest analysis. Results Radiological failure and revision rates were 23% and 12.5%, respectively. Revisions were undertaken at a mean of 25.1 months (sd 26.4) postoperatively. Patients with radiological failure were younger at the time of the initial procedure, were less likely to have a diagnosis of primary osteoarthritis (OA), were more likely to have had ischial screws in previous surgery, had fewer ischial screw holes in their CFAC design, and had more proximal ischial fixation. Random forest analysis identified the age of the patient and the number of locking and non-locking screws used for inclusion in subsequent bivariable logistic regression, but only age (odds ratio 0.93 per year) was found to be significant. Conclusion We identified both patient and design features predictive of CFAC survivorship. We found a higher rate of failure in younger patients, those whose primary diagnosis was not OA, and those with more proximal ischial fixation or fewer ischial fixation options.

DOI： 10.1302/0301-620X.101B6.BJJ-2018-1455.R1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Measures of long-term success of total hip arthroplasty (THA) over the past 50 years have focused primarily on implant survival, with less evidence on long-term functional outcomes. Questions/Purposes: We aimed to study 20-to-40-year functional outcomes after primary THA. We investigated the extent to which (1) functional outcomes after THA are maintained long term; (2) patient characteristics such as age, hip disease diagnosis, and comorbidities affect recovery of function and survivorship after THA; and (3) patients’ overall function after THA is affected by the need for revision, the aging process, and associated comorbidities. Methods: We retrospectively reviewed outcomes of the senior author’s patients between 1968 and 1993. Of 1207 patients, we identified 167 patients (99 female, 68 male; 276 primary THAs) who were at least 65 years old at follow-up and had at least 20 years of follow-up. Mean age at surgery was 55 years; mean follow-up time was 27 years. Bilateral THAs were performed in 109 patients (65%), and revisions in 81 patients (48.5%). Clinical outcomes including pain level, walking ability, range of motion, and overall function were determined by the Hospital for Special Surgery (HSS) hip scoring system. Contralateral and revision surgery, as well as patient age, sex, and body mass index, were included as covariates. To account for unequally spaced follow-up time points and competing causes of functional decline (e.g., age, contralateral hip disease, and need for revision THA), a latent class mixed model approach was used to identify unobserved classes of patients who had similar outcomes. Linear, quadratic, and piecewise-polynomial growth models were considered for class identification. The best fitting model was determined based on Bayesian information criterion. Results: A four-class model of this patient population was identified: (1) the Elderly Class, who had a mean age of 62 years at the time of primary THA; (2) the Bilateral Class, who underwent simultaneous or staged bilateral THA; (3) the Revision Class, who required at least one revision; and (4) the Youngest Class, who had a mean age of 49 years. After an initial period of improvement in all groups, the functional trajectory diverged according to classifications. Age was the strongest determinant of long-term outcome, with HSS hip scores in the Elderly Class declining after about 20 years. The Youngest Class maintained good-to-excellent hip function for over 30 years. Revision THA and contralateral THA accounted for a temporary decline in function, after which overall good function was regained for the long term. Conclusions: All classes in the study population enjoyed good-to-excellent outcomes after THA for about 20 years. Thereafter, functional decline was attributed more to aging than to the need for revision. One or more revision THA did not negatively influence long-term clinical outcomes, suggesting that, even for younger patients, symptoms, rather than the avoidance of possible revision, should be the primary determining factor when indicating THA.

DOI： 10.1007/s11420-019-09676-0

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Peripheral nerve injury (PNI) is a devastating complication following total hip arthroplasty (THA). The purpose of this study was to identify risk factors for PNI after THA using a New York Statewide Planning and Research Cooperative System (SPARCS). Methods: The SPARCS database was queried to identify patients who had undergone THA from 1996 to 2011. Patient demographics, medical history, surgical details, hospital characteristics, and in-hospital complications were recorded. Cases in which a new unilateral PNI was identified were compiled, as were control cases in which a new PNI did not occur. The characteristics of cases and controls underwent univariate testing and a multivariate logistic regression using Akaike information criterion model selection to identify risk factors for the development of PNI after THA. Results: 207,981 cases were identified, and 487 were coded as having a new PNI. Preexisting spinal conditions (odds ratio [OR] = 2.55, confidence interval [CI] = 1.61-3.83) were strongly correlated with the development of PNI postoperatively, as was dislocation (OR = 2.58, CI = 1.01-5.30) and diabetes with chronic complications (OR = 2.26, CI = 0.96-4.43). Younger age, in-hospital complications, and thromboembolic events were also associated with postoperative PNI. Conclusion: The incidence of PNI after THA was consistent with previous large-scale studies but may under-represent the true incidence because of undercoding inherent in large database studies. Previous spine disorder, chronic diabetes, younger age, and in-hospital postoperative complications all increased the risk of PNI. This study can help health-care providers and systems identify patients at higher risk of this serious complication.

DOI： 10.1016/j.arth.2019.03.043

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Postsurgical acute nerve injury is rare but potentially devastating following total hip arthroplasty (THA). Previous literature suggests a wide range of incidence from 0.1% to 7.6%. Confirmed risk factors for these injuries remain unclear. Methods: THA patients at our institution who developed nerve injury during their admission for THA between January 1, 1998, and December 31, 2013, were systematically identified and matched with 2 control subjects by surgical date. Relevant patient and surgical data were obtained through review of patient charts and electronic health records. We identified potential risk factors and calculated odds ratios (OR) using a conditional logistic regression model with a parsimonious stepwise approach. Results: We identified 93 nerve injuries in 43,761 THAs (0.21%). The mean age of cases was 63 years. Adjusting for other factors in the model, patients <45 years were found to be at increased risk of developing nerve injury (OR, 7.17; P =.033). Similarly, patients with a history of tobacco use (OR, 1.90; P =.030) and a history of spinal surgery or disease (OR, 10.06; P <.001) were also associated with increased risk of nerve injury. For every 30-minute increase in surgery time after 1 hour, risk of nerve injury risk increased (OR, 1.48; P =.034). Assignment as first operative case of the morning was associated with a decreased risk of nerve injury (OR, 0.37, P =.043). Conclusion: This study demonstrates that nerve injury is a rare complication following THA at our institution. We found risk factors that are possibly modifiable factors such as lumbar spine disease, smoking, and time of surgical scheduling.

DOI： 10.1016/j.arth.2018.09.008

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The purpose of this study was to evaluate the psychometric properties of the Patient-Reported Outcomes Measurement Information System (PROMIS) physical function computer adaptive test (PF-CAT) relative to the American Shoulder and Elbow Surgeons (ASES) score in patients with glenohumeral osteoarthritis undergoing primary anatomic total shoulder arthroplasty (TSA). Methods: A retrospective study of an institutional TSA registry was performed. Preoperative PROMIS PF-CAT and ASES scores were collected. Floor and ceiling effects were determined, and convergent validity was established through Pearson correlations. Rasch partial credit modeling was used for psychometric analysis of the validity of PF-CAT and ASES question items. Person-item maps were generated to characterize the distribution of question responses along the latent dimension of shoulder disability. Results: Responses from 179 patients (184 shoulders) were included. PF-CAT had a moderate correlation to ASES (r = 0.487; P <.001), with no floor or ceiling effects; ASES had a 1.1% floor effect and no ceiling effect. With iterative Rasch model item-reduction analysis eliminating poorly fitting question items, all possible PF-CAT items were eliminated after 6 iterations. With ASES, just 1 function question item was dropped. Person-item maps showed ASES to be superior to PROMIS PF-CAT psychometrically, with sequential and improved coverage of the latent dimension of shoulder disability. Conclusion: Despite moderate correlation with ASES, PROMIS PF-CAT demonstrated inferior validity and psychometric properties in patients undergoing TSA. PF-CAT should not replace the ASES in this population of patients.

DOI： 10.1016/j.jse.2019.02.011

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Peripheral nerve injury (PNI) is a devastating complication following total knee arthroplasty (TKA). The purpose of this study is to identify risk factors for PNI after TKA using a New York Statewide Planning and Research Cooperative System. Methods: The Statewide Planning and Research Cooperative System database was queried to identify patients who had undergone TKA from 1996 to 2014. Patient demographics, medical history, surgical details, hospital characteristics, and in-hospital complications were recorded. Cases in which a new unilateral PNI was identified were compiled, as were control cases. The characteristics of cases and controls underwent univariate testing and a multivariate logistic regression using Akaike information criterion model selection to identify risk factors for the development of PNI after TKA. Results: In total, 383,060 cases were identified and 0.12%, or 445/383,060, experienced a new PNI. Pre-existing spinal conditions (odds ratio [OR] 1.98, confidence interval [CI] 1.08-3.30) and valgus deformity (OR 4.19, CI 2.46-6.66) were strongly correlated with the development of PNI postoperatively individually, but together increased risk substantially (OR 17.28, CI 2.83-55.35). Younger age (<50 years), in-hospital complications, female gender, and bilateral surgery were all associated with postoperative PNI, as well. Conclusion: Valgus deformity and previous spine disorder together greatly increased the risk of PNI after TKA. Younger age, female gender, and in-hospital postoperative complications all increased the risk of PNI, as well. This study quantifies the relative risk each of these factors impart in the development of PNI after TKA and can help healthcare providers and systems identify and counsel patients at higher risk of this serious complication.

DOI： 10.1016/j.arth.2019.05.008

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: The purpose of this study was to perform a population-level analysis to evaluate the effect of socioeconomic markers on the use of meniscus surgery in patients with meniscus tears. Methods: We queried all hospital-based clinic visits from 2011 to 2014 in the Statewide Planning and Research Cooperative System database, which also contains all New York inpatient/outpatient visits. Patients with known prior knee surgery, meniscus tear before 2011, or other ligament injuries were excluded. The primary outcome was a meniscus procedure (meniscectomy or meniscus repair). Survival analysis was used to calculate the rate of meniscus surgery within 6 months. A multivariate model identified patient factors (age, sex, race, and payer) associated with surgical intervention. Results: There were 32,012 patients identified who met the inclusion criteria. The rate of meniscus procedure within 6 months of diagnosis was 49.6%. Meniscectomy was performed in 98.8% of cases compared with 1.2% for meniscus repair. Rates of meniscus procedures were higher in patients who were older, male, and white, as well as those first diagnosed by a surgeon. The highest rates of meniscus procedures were in those with private, worker's compensation, or other insurance types. Multivariable analysis showed that female sex, non-white race, and public or self-pay insurance were independently associated with lower rates of meniscus surgery. Conclusions: These results suggest both insurance-based and race-based disparities regarding surgical treatment. Additionally, the strongest variable for surgical management was a meniscus tear being first diagnosed by a surgeon. Level of Evidence: Level of Evidence IV, retrospective case-control study.

DOI： 10.1016/j.arthro.2018.04.020

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: To determine if new-onset perioperative atrial fibrillation during arthroplasty represents a benign response to intraoperative cardiac stress or is a risk factor for stroke, we evaluated the subsequent risk of ischemic stroke in patients with new-onset atrial fibrillation occurring during primary total knee arthroplasty (TKA) and total hip arthroplasty (THA). Methods: Discharge data of all adult patients undergoing primary TKA or THA from 1997 to 2013 were queried via the New York Statewide Planning and Research Cooperative System database to find patients with new-onset perioperative atrial fibrillation. These patients were then followed up over time to determine their risk of ischemic stroke. Results: Of the 312,636 TKA and 215,610 THA unique patient admissions, 3646 (0.7%) had a diagnosis of new-onset perioperative atrial fibrillation. The cohort of patients with this finding was 58.9% female with an average age of 73.6 years and higher prevalence of vascular risk factors. Adjusting for validated stroke risk factors, the risk of ischemic stroke within 1 year after THA or TKA in patients with new-onset atrial fibrillation was 2.7 times higher than in those without a history of atrial fibrillation (odds ratio: 2.7, 95% confidence interval: 1.5-4.8). Hospital length of stay and charges for patients with new-onset atrial fibrillation were also greater than patients with either a prior diagnosis or no diagnosis of atrial fibrillation. Conclusion: New-onset atrial fibrillation during TKA and THA may indicate risk of ischemic stroke following surgery that should warrant medical follow-up and may increase hospital length of stay and charges.

DOI： 10.1016/j.arth.2018.04.009

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Introduction: The relationship between postoperative tibiofemoral ligament balance and patient satisfaction in total knee arthroplasty (TKA) has been explored previously. However, the optimal intraoperative medial–lateral ligament balance during knee flexion in terms of postoperative patient satisfaction remains unknown. We evaluated the effect of intraoperative flexion instability on patient satisfaction after TKA. Materials and methods: This study consisted of 46 knees with varus osteoarthritis undergoing TKA. Medial–lateral component gaps at 0° knee extension and 90° flexion were measured intraoperatively using a knee balancer. Differences in postoperative patient outcomes at 3 weeks and 1 year were compared between medially tight knees in 90° flexion with a medial component gap of < 4 mm and medially loose knees in 90° flexion with a gap of ≥ 4 mm. Outcomes were measured using the 2011 Knee Society Scoring System (2011 KS). Results: The median total 2011 KS score at 1 year postoperatively in the medially loose knees [median 97; interquartile range (IQR) 75–117] was significantly lower than that in the medially tight knees (median 128; IQR 104–139, P < 0.01), while preoperative and 3-week postoperative scores were similar. In addition, medial flexion gaps were not significantly associated with total 2011 KS scores before surgery or at 3 weeks postoperatively. However, at 1 year after surgery, medial component flexion gaps were negatively associated with the total 2011 KS score (R = − 0.42; P < 0.01) and the 2011 KS satisfaction subscale score (R = − 0.36; P = 0.01). Conclusions: Excessive intraoperative medial joint laxity of ≥ 4 mm at 90° flexion progressively decreased patient satisfaction for 1 year. Since intraoperative medial laxity in flexion is likely to interfere with functional recovery after TKA, medial stabilization during TKA is important throughout knee flexion. Level of evidence: Therapeutic study, Level III.

DOI： 10.1007/s00402-018-2965-2

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Study Design. Retrospective state database analysis. Objective. To quantify the 30- A nd 90-day emergency department (ED) utilization and inpatient readmission rates after primary cervical arthrodesis, to stratify these findings by surgical approach, and to describe risk factors and conditions precipitating these events. Summary of Background Data. Limited data exist on ED utilization and hospital readmission rates after cervical spine arthrodesis. Methods. The New York State all-payer health-care database was queried to identify all 87,045 patients who underwent primary subaxial cervical arthrodesis from 1997 through 2012. Demographic data and clinical information were extracted. Readmission data were available for the entire study period, whereas ED utilization data collection began later and was therefore analyzed starting in 2005. Incidences of these events within 30 and 90 days of discharge as well as trends over time were tabulated. The conditions prompting these encounters were also collected. Data were analyzed with respect to surgical approach. Results. The hospital readmission rate was 4.2% at 30 days and 6.2% at 90 days postoperatively. Approximately 6.2% of patients were managed in the ED without inpatient admission within 30 days and 11.3% within 90 days of surgery. The most common conditions prompting such events were dysphagia or dysphonia, respiratory complications, and infection. ED utilization and readmission rates were lowest after anterior surgeries. A preoperative Charlson Comorbidity Index of 1 or greater and traumatic pathologies were associated with increased risk of subsequent ED utilization or hospital readmission. Thirty-day hospital readmission rates declined after 2010, whereas 30-day ED utilization continued to increase. Conclusion. Patient comorbidities, traumatic pathologies, and surgical approach are associated with increased postoperative complications. Anterior procedures carry the lowest risk, followed by posterior and then circumferential. Awareness of these findings should help to encourage development of strategies to minimize the rate of postoperative ED utilization and hospital readmission.

DOI： 10.1097/BRS.0000000000002518

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Despite potential concerns regarding their validity, physician-rating websites continue to grow in number and utilization and feature prominently on major search engines, potentially affecting patient decision-making regarding physician selection. Questions/Purposes: We sought to determine whether patient ratings on public physician-rating websites correlate with surgeon-specific outcomes for high-volume total knee replacement (TKR) surgeons in New York State (NYS) from 2010 to 2012. Methods: Online patient ratings were compared to surgeon-specific outcomes from the Statewide Planning and Research Cooperative System (SPARCS) database from the NYS Department of Health. For each surgeon, we determined the infection rate, re-admission rate, and revision surgery rate within the study period, as well as the mean inpatient length of stay, for TKR from the SPARCS database. Online ratings were collected from two physician-rating websites (Vitals.com and HealthGrades.com). Results: One hundred seventy-four high-volume TKR surgeons were identified in NYS from 2010 to 2012. The mean rates of in-hospital infection, 90-day infection, 30-day re-admission, 90-day re-admission, and revision surgery were 0.25, 1.00, 4.89, 8.43, and 1.31%, respectively. The mean number of ratings for individual surgeons on HealthGrades.com and Vitals.com were 24.0 (range: 0 to 109) and 19.3 (range: 0 to 114), respectively, and mean overall ratings were 4.2 and 4.1 (out of 5) stars, respectively. As with online patient ratings of individual surgeons, variability was observed in the total adverse event rate distribution for individual surgeons. Despite sufficient variability in both online patient rating and surgeon-specific outcomes for high-volume TKR surgeons in NYS, no correlation was observed. Conclusion: There was no correlation between surgeon-specific TKR outcome measures and online patient ratings. We therefore advise that patients exert caution when interpreting ratings on these websites.

DOI： 10.1007/s11420-017-9600-6

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Monitored rehabilitation has long been considered an essential part of the recovery process in total knee arthroplasty (TKA). However, the optimal setting for rehabilitation remains uncertain. We sought to determine whether inpatient rehabilitation settings result in improved functional and patient-reported outcomes after primary TKA. Methods: All patients undergoing primary TKA from May 2007 to February 2011 were identified from our institutional total joint registry. Propensity score matching was then performed, resulting in a final cohort of 1213 matched pairs for discharge destination to either home or a rehabilitation facility (inpatient rehab or skilled nursing facility). Length of stay, need for manipulation, 6-month complications, and 2-year Western Ontario and McMaster Universities Osteoarthritis Index, Lower Extremity Activity Scale, 12-item Short Form Health Survey, and Hospital for Special Surgery knee expectations surveys were compared. Results: Patients discharged to a rehab facility were noted to have a shorter hospital length of stay (5.0 vs 5.4 days). Patients discharged to inpatient rehabilitation reported more fractures at 6 months postoperatively. However, no differences in manipulation rates, 2-year outcome scores, or changes in outcome scores were found between the 2 groups. Conclusion: Inpatient rehabilitation settings did not result in lower complications at 6 months or improved functional or patient-reported outcomes at 2 years compared to discharge directly to home when patients are propensity matched for age, living situation, comorbidities, baseline functional status, and insurance status. This finding has important cost implications and calls into question whether the healthcare system should allow otherwise healthy patients to use inpatient rehabilitation services postoperatively after primary TKA.

DOI： 10.1016/j.arth.2017.12.033

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective: To identify the most appropriate imputation method for missing data in the HCUP State Inpatient Databases (SID) and assess the impact of different missing data methods on racial disparities research. Data Sources/Study Setting: HCUP SID. Study Design: A novel simulation study compared four imputation methods (random draw, hot deck, joint multiple imputation [MI], conditional MI) for missing values for multiple variables, including race, gender, admission source, median household income, and total charges. The simulation was built on real data from the SID to retain their hierarchical data structures and missing data patterns. Additional predictive information from the U.S. Census and American Hospital Association (AHA) database was incorporated into the imputation. Principal Findings: Conditional MI prediction was equivalent or superior to the best performing alternatives for all missing data structures and substantially outperformed each of the alternatives in various scenarios. Conclusions: Conditional MI substantially improved statistical inferences for racial health disparities research with the SID.

DOI： 10.1111/1475-6773.12704

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Introduction: In this we study identified potential risk factors for post−total knee arthroplasty (TKA) nerve injury, a catastrophic complication with a reported incidence of 0.3%−1.3%. Methods: Patients who developed post-TKA nerve injury from 1998 to 2013 were identified, and each was matched with 2 controls. A multivariable logistic regression model was built to calculate odds ratios (ORs). Results: Sixty-five nerve injury cases were identified in 39,990 TKAs (0.16%). Females (OR 3.28, P = 0.003) and patients with history of lumbar pathology (OR 6.12, P = 0.026) were associated with increased risk of nerve injury. Tourniquet pressure < 300 mm Hg and longer duration of anesthesia may also be risk factors. Discussion: Surgical planning for females and patients with lumbar pathology should be modified to mitigate their higher risk of neurologic complications after TKA. Our finding that lower tourniquet pressure was associated with higher risk of nerve injury was unexpected and requires further investigation. Muscle Nerve 57: 946–950, 2018.

DOI： 10.1002/mus.26045

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The rate of cervical spinal fusion has been increasing significantly. However, there is a paucity of literature describing trends based on surgical approach using complete population databases. We investigated the approach-based trends in epidemiology, indications, and in-hospital outcomes of cervical spinal fusion. Methods: New York's Statewide Planning and Research Cooperative System database was queried to identify patients who underwent primary subaxial cervical fusion from 1997 to 2012. Demographic and clinical information was obtained. Subgroup analyses were performed based on surgical approach: anterior (A), posterior (P), and circumferential (C). Results: A total of 87,045 cervical fusions were included. Over the study period, the population-adjusted annual fusion rate increased from 23.7 to 50.6 per 100,000 population (P < 0.001). A fusion was most common (85.2%), followed by P (12.3%), and C (2.5%). Mean ages were 49.8 ± 11.9, 59.9 ± 15.2, and 55.1 ± 14.5 years (P < 0.001), respectively. Although rates remained steady among younger patients, they increased for older patients. Overall, degenerative conditions were the predominant indications for surgery and increased in rate over time. The mean length of stay was: A, 3.1 ± 10.5; P, 9.1 ± 14.1; and C, 14.1 ± 22.5 days (P < 0.001). Rates of in-hospital complications were A, 3.0%; P, 10.5%; and C, 18.9% (P < 0.001), and mortality was A, 0.3%, P, 1.8%, and C, 2.5% (P < 0.001). Conclusions: The rate of subaxial spinal fusions increased 114% from 1997 to 2012 in New York State. Rates remained stable in younger patients but increased in the older population. Preoperative indications and postoperative courses differed significantly among the various approaches, with patients undergoing anterior fusion having better short-term outcomes.

DOI： 10.1016/j.wneu.2018.02.004

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Hip arthroscopy has emerged as a successful option for the treatment of femoroacetabular impingement and related hip disorders, but the procedure is technically challenging. Purpose: To define the learning curve through which surgeons become proficient at hip arthroscopy. Study Design: Cohort study; level of evidence, 3. Methods: The authors identified hip arthroscopy procedures performed by surgeons through a New York State database (Statewide Planning and Research Cooperative System) and followed those cases for additional hip surgery (total hip arthroplasty, hip resurfacing, or ipsilateral hip arthroscopy) within 5 years of the original procedure. Career volume for each case was calculated as the number of hip arthroscopy procedures that the surgeon had performed. Volume strata were identified via the stratum-specific likelihood ratio method. A Cox proportional hazards model was used to measure the effect of surgeon career volume on risk of additional hip surgery, adjusting for the following patient characteristics: age, sex, race/ethnicity, insurance type, and concurrent diagnosis of hip osteoarthritis. Results: Among 8041 hip arthroscopies performed by 251 surgeons, 989 (12.3%) cases underwent additional hip surgery within 5 years. Four strata of surgeon career volume associated with distinct frequencies of reoperation were identified: cases in the lowest stratum (0-97) had the highest frequency of additional surgery (15.4%). Frequencies declined for cases in the medium (98-388), high (389-518), and highest (≥519) strata (13.8%, 10.1%, and 2.6%, respectively). There was an increased risk of subsequent surgery in each stratum when compared with the highest stratum (hazard ratio [95% CI]: low volume, 3.22 [2.29-4.54]; medium, 3.40 [2.41-4.82]; high, 2.81 [1.86-4.25]; P <.0001 for all). Patients with a diagnosis of hip osteoarthritis had increased risk of subsequent hip arthroplasty or resurfacing (2.46 [2.09-2.89], P <.0001). Risk also increased with age: 30 to 39 vs ≤29 years (5.12 [3.29-8.00], P <.0001), 40 to 49 vs ≤29 years (11.30 [7.43-17.190], P <.0001), ≥50 vs ≤29 years (18.39 [12.10-27.96], P <.0001). Increased age and osteoarthritis were not risk factors for revision hip arthroscopy. Conclusion: The learning curve for hip arthroscopy was unexpectedly demanding. Cases performed by surgeons with career volumes ≥519 had significantly lower risk of subsequent hip surgery than those performed by lower-volume surgeons.

DOI： 10.1177/0363546517749219

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Publication of 2 (negative) randomized clinical trials (RCTs) in 2002 and 2008 demonstrating inefficacy of arthroscopic debridement of the knee (ADK) for osteoarthritis, and a 2004 national non-coverage Medicare determination, have decreased overall ADK utilization. However, because of potentially favorable outcomes associated with high volume, surgeons performing high arthroscopy volume may be slower to abandon performing ADK than would low volume surgeons. We examined the trends in ADKs performed by high and low volume surgeons before and after these 2 trials and the Medicare determination. New York state residents 40 years and older undergoing outpatient ADK from 1997 to 2010 were identified from a statewide database, and monthly population-based age and sex-adjusted ADK rates were calculated. We estimated the change in utilization trends over time, stratified by surgeon annual arthroscopy volume, for Medicare and non-Medicare patients. 1386 surgeons performed 29,658 ADKs during the study period, with the proportion performed by high volume surgeons increasing from 22% in 1997 to 66% in 2010. Overall monthly ADK rates declined from 2.4 to 1.3 per 100,000 population (45%) over the study period. Rates of ADK performed by high volume surgeons increased after the first RCT in the non-Medicare population and after the CMS decision in the Medicare population, and decreased after the second RCT. With more definitive evidence from the second negative trial, high volume surgeons performed less ADKs, suggesting that multiple RCTs with consistently negative results are needed to change practice of high volume surgeons.

DOI： 10.1016/j.conctc.2017.11.011

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: To identify the factors influencing spinal sagittal alignment, bone mineral density (BMD), and Oswestry Disability Index (ODI) outcome measures in patients with rheumatoid arthritis (RA). Methods: We enrolled 272 RA patients to identify the factors influencing sagittal vertical axis (SVA). Out of this, 220 had evaluation of bone mineral density (BMD) and vertebral deformity (VD) on the sagittal plane; 183 completed the ODI questionnaire. We collected data regarding RA-associated clinical parameters and standing lateral X-ray images via an ODI questionnaire from April to December 2012 at a single center. Patients with a history of spinal surgery or any missing clinical data were excluded. Clinical parameters included age, sex, body mass index, RA disease duration, disease activity score 28 erythrocyte sedimentation rate (DAS28-ESR), serum anti-cyclic citrullinated peptide antibody, serum rheumatoid factor, serum matrix metalloproteinase-3, BMD and treatment type at survey, such as methotrexate (MTX), biological disease-modifying anti-rheumatic drugs, and glucocorticoids. We measured radiological parameters including pelvic incidence (PI), lumbar lordosis (LL), and SVA. We statistically identified the factors influencing SVA, BMD, VD, and ODI using multivariate regression analysis. Results: Multivariate regression analysis showed that larger SVA correlated with older age, higher DAS28-ESR, MTX nonuse, and glucocorticoid use. Lower BMD was associated with female, older age, higher DAS28-ESR, and MTX nonuse. VD was associated with older age, longer disease duration, lower BMD, and glucocorticoid use. Worse ODI correlated with older age, larger PI-LL mismatch or larger SVA, higher DAS28-ESR, and glucocorticoid use. Conclusions: In managing low back pain and spinal sagittal alignment in RA patients, RA-related clinical factors and the treatment type should be taken into consideration.

DOI： 10.1007/s00586-017-5401-3

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Patients undergoing total knee arthroplasty expect pain relief, functional improvement, and a return to physical activity. The objective of this study was to determine the impact of patients' baseline physical activity level on preoperative expectations, postoperative satisfaction, and clinical outcomes in patients undergoing total knee arthroplasty. Methods: Using an institutional registry from 2007 to 2012, we retrospectively identified patients who underwent a unilateral primary total knee arthroplasty for osteoarthritis and completed a preoperative Lower Extremity Activity Scale (LEAS), a Hospital for Special Surgery Knee Replacement Expectations Survey (HSS-KRES), and a Knee injury and Osteoarthritis Outcome Score (KOOS) evaluation in addition to 2-year KOOS and satisfaction evaluations. Active patients were defined by an LEAS level of 13 to 18. Active patients (n = 1,008) were matched to inactive patients (n = 1,008) by age, sex, body mass index, and comorbidities. The cohorts were compared with regard to the association of expectations with KOOS and satisfaction, the change in LEAS level from baseline to 2 years, complications, and revision surgical procedures. Multivariable analyses identified predictors of satisfaction, KOOS, and revision surgical procedures. Results: Significantly more active patients (68.2%) expected to be back to normal with regard to the ability to exercise and participate in sports compared with inactive patients (55.5%; p < 0.0001). Although overall satisfaction was equivalent, active patients were more commonly very satisfied with regard to the ability to do recreational activities (67.2% compared with 57.7%; p = 0.001). There were no associations between expectations and satisfaction or outcomes. Only the inactive patient group improved in activity level at 2 years. At 2 years, 69.5% of the inactive patients and 27.3% of the active patients improved upon their baseline activity levels (p < 0.0001). Complications rates were similar. The revision rate was higher for active patients (3.2%) compared with inactive patients (1.6%) at 5 to 10 years postoperatively (p = 0.019). Conclusions: At 2 years following total knee arthroplasty, inactive patients improved from baseline activity levels and active patients did not. Active patients had an elevated revision risk. Therefore, active patients should be carefully counseled regarding total knee arthroplasty to give them an understanding of its limitations and the potential risk of future revision. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.17.00920

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background Patient-reported outcome measures (PROMs) are a gold standard for measuring therapeutic outcomes in research. Extending their use to informclinical care decisions, determine the appropriateness of therapeutic choices, and assess healthcare quality is attractive but will require our professional community to establish valid estimates of minimal and substantial clinical improvements. Questions/purposes The purposes of this study were (1) to assess the validity of estimates for the minimal clinically important difference (MCID) calculated using distribution and anchor-based methods by determining whether they exceed the minimal detectable change (MDC) for the Hip Disability and Osteoarthritis Outcome Score (HOOS) and the Knee Injury and Osteoarthritis Outcome Score (KOOS) domains, the HOOS, joint replacement (JR) and the KOOS, JR among patients who underwent THA or TKA; (2) to determine substantial clinical benefit thresholds for the HOOS and KOOS domains, the HOOS, JR, and the KOOS, JR among patients who underwent THA or TKA; and (3) to assess the proportions of patients who underwent THA or TKA who achieved an MCID for the HOOS and KOOS domains, HOOS, JR, and KOOS, JR based on distribution-based and anchor-based methods as well as the percentages of patients who achieved substantial clinical benefit using the anchor-based method. Methods Medicare patients enrolled in our institutional joint replacement registry who subsequently underwent THA (n = 2323) or TKA (n = 2630) between 2007 and 2012 completed HOOS or KOOS preoperatively and 2 years postoperatively. Short-form joint replacement (JR) versions of each PROM were derived from the full PROMs. Of all eligible patients, 78% (3161 of 4080) of THAs and 74% of TKAs (3815 of 5156) consented to join the registry and completed a baseline survey, 88% (2796 of 3161) of THAs and 85% (3230 of 3815) of TKAs were eligible for followup survey administration, and 83% of THAs (2323 of 2796) and 81% (2630 of 3230) of TKAs returned 2-year surveys. For each HOOS domain, KOOS domain, HOOS, JR, and KOOS, JR, we calculated the calibration variation of the instrument (MDC) with confidence intervals (CIs) reflecting 80% (MDC80), 90% (MDC90), and 95% (MDC95) certainty; we calculated the smallest difference joint health patients might detect (MCID) using distribution- and anchor-based approaches and the difference that can be considered a large improvement in joint health (substantial clinical benefit) using an anchor-based approach. Results Patients undergoing THA were 57% female with a mean (± SD) age of 73 ± 6 years, whereas patients undergoing TKA were 63% female with a mean age of 74±6 years. Depending on the CI chosen for the MDC, values ranged from 7 to 16 for the HOOS and KOOS domains and the JRs. The MCIDs ranged from 6 to 9 for the distributionbased approach and 7 to 36 for the anchor-based approach. All HOOS and KOOS domains and all JR scores are scores from 0 (worst joint health) to 100 (best joint health). The MCIDs calculated using the distribution-based approach were not valid, because they were lower than the MDC for all HOOS/KOOS domains and both JRs at every confidence level. The anchor-based receiver operating characteristic approach, on the other hand, resulted in MCIDs exceeding MDC80 for seven of eight HOOS/KOOS domains and MDC95 for both JR scores. For all domains and JR versions, substantial clinical benefits ranged from 15 to 36, exceeding MDC95 in all domains and JR scores. Across HOOS and KOOS domains as well as the JR, the proportion of patients undergoing THA who achieved an MCID ranged from 77% to 95% with the distribution-based method and from 67%to 96%using the anchor-based method. The proportion achieving substantial clinical benefit ranged from 67% to 85%. Conclusions The MDC and MCID differ greatly based on assumptions and methods used. The MCID anchor-based approach had superior construct and face validity compared with the MCID distribution-based approach, which never exceeded even small MDCs. Achieving consensus about standard definitions of meaningful improvement will be necessary to maximize utility of these PROMs to inform clinical care or performance measurement.

DOI： 10.1097/CORR.0000000000000456

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Studies of volume-outcome relationships typically subdivide volume via non-evidence-based methods, producing categories that vary widely among studies, preclude the comparison of results, and possibly obscure the true volume-outcome relationships. The goal of the current study was to use quantitative methods to derive meaningful, riskbased categories for hospital and surgeon total hip arthroplasty (THA) volume based on relationships with mortality, complications, and revision. Methods: Using New York statewide patient data (1997 to 2014; n = 187,557), we derived risk-based hospital and surgeonvolume categories for primary THA based on relationships with 90-day complications and mortality and 2-year revision. Results: The following categories, based on relationships with complications, mortality, and revision, were derived for surgeon volume: 0 to 12, 13 to 25, 26 to 72, 73 to 165, 166 to 279, and ‡280 THA/year. For hospital volume, the categories derived were 0 to 11, 12 to 54, 55 to 157, 158 to 526, and ‡527 THA/year. More than 35% of THA cases in New York State were conducted by surgeons performing £1 THA/month (0 to 12 THA/year), and these were associated with a 2 to 2.5-fold increase in the risk for complications, mortality, and revision relative to higher-volume surgeons. Similarly, 15% of THA cases in New York State were conducted in hospitals performing £1 THA/week (0 to 11 or 12 to 54 THA/year), and these were associated with a nearly 1.5-fold increase in complications and between a 4 and 6-fold increase in mortality. Traditional non-evidence-based quartile categories were concentrated at lower volumes, did not capture the full magnitude of the volume-related differences, and were a poorer representation of the outcome data, as assessed by several model metrics. Thus, quartiles showed only a <2-fold increase in complications, mortality, and revision for the lowest versus the highest surgeon-volume quartile and failed to show the increased risk for lower versus higher hospital volumes. Conclusions: The volume-outcome relationships in THA are more pronounced than previously apparent through standard statistical techniques. Volume-based strategies for improving outcomes in THA should use benchmarks that are evidencebased to achieve optimal results. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.17.00967

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Carpal tunnel release (CTR) has traditionally been performed through an open approach, although in recent years endoscopic CTR has gained in popularity. Questions/Purposes: We sought to assess whether a difference exists between the rates of nerve repair surgery following open versus endoscopic CTR in New York State (NYS). Methods: Patients undergoing endoscopic and open CTR from 1997 to 2013 were identified from the Statewide Planning and Research Cooperative System (SPARCS) database from the NYS Department of Health using Current Procedural Terminology, 4th Revision (CPT-4) codes 29848 and 64721, respectively. The primary outcome measure was subsequent nerve repair surgery (as identified using CPT-4 codes 64831–64837, 64856, 64857, 64859, 64872, 64874, and 64876). Other variables analyzed included patient age, sex, payer, and surgery year. Results: There were 294,616 CTRs performed in NYS from 1997 to 2013. While the incidence of open CTR remained higher than endoscopic CTR, the proportion of endoscopic CTR steadily increased, from 16% (2984/19,089) in 2007 to 25% (5594/22,271) in 2013. For the 134,143 patients having a single CTR, the rate of subsequent nerve repair was significantly higher following endoscopic CTR (0.09%) compared to open CTR (0.04%). The Cox model showed that factors significantly associated with a higher risk of subsequent nerve repair surgery were endoscopic CTR and younger age. Conclusions: Endoscopic CTR has been increasingly performed in NYS and associated with a higher rate of subsequent nerve repair. This rate likely underestimates the incidence of nerve injuries because it only captures those patients who had subsequent surgery. While this catastrophic complication remains rare, further investigation is warranted, given the rise of endoscopic CTR in the setting of equivalent outcomes, but favorable reimbursement, versus open CTR.

DOI： 10.1007/s11420-018-9637-1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: Knee-specific patient reported outcome measures (PROMs) are important tools in evaluating the effectiveness of sports medicine interventions. The PROMs were originally developed for paper administration, but electronic data capture technologies offer potential benefits such as increased efficiency and accuracy. The aim of this study was to assess the validity of touch screen versus paper administration using several common knee-specific and general health surveys. Methods: Agreement between scores was compared for knee-specific PROMs administered on paper versus computer; paper versus tablet; computer versus tablet in 60 patients per group undergoing ACL reconstruction. Surveys were given at pre-operative assessment and between 1 and 7 days later. Weighted kappa statistic (κ) and intraclass correlation coefficients (ICC) were calculated to test agreement between the two modalities in: IKDC Subjective Knee Form, Marx Activity Scale, Tegner Activity Level Scale, and Lysholm Knee Scale. SF-12 Physical and Mental Component Summary scores were also assessed. Results: Response rate was over 90 %. Mean age was 29.6 ± 10.9 years, with patients in the paper–computer cohort being 4 years older than in the other groups. Agreement was substantial or better for all PROMs collected: IKDC Subjective (ICC: 0.79); Marx (ICC: 0.70); Lysholm (ICC: 0.65); and Tegner (κ = 0.67). Agreement for the SF-12 PCS (ICC: 0.77) and MCS (ICC: 0.73) was also found to have substantial agreement. Conclusion: In conclusion, touch screen-based PROMs are a valid capture method, providing reliable results relative to traditional paper survey administration. Digital methods of direct data capture may also foster multi-centre collaborations and allow for more accurate comparisons of outcomes between patient groups in clinical practice and orthopaedic research. Level of evidence: II.

DOI： 10.1007/s00167-016-4189-8

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s11420-017-9544-x

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Orthopedic studies are occasionally published in high-impact general medical journals; these studies are often given high visibility and have significant potential to impact health care policy and inform clinical decision-making. The purpose of this review was to investigate the characteristics of operative orthopedic studies published in high-impact medical journals. The number of orthopedic studies published in high-impact medical journals is relatively low; however, these studies demonstrate methodological characteristics that may bias toward nonoperative treatment. Careful analysis and interpretation of orthopedic studies published in these journals is warranted.

DOI： 10.3928/01477447-20170223-04

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objectives: Proximal humerus fractures are a common injury in the elderly population that can usually be managed non-operatively. However, arthroplasty has become increasingly utilized for complex fractures and poor bone quality. We evaluated national trends in treatment, specifically looking at the adoption of reverse total shoulder arthroplasty. Methods: The incidence of proximal humerus fractures was calculated from the Nationwide Emergency Department Database (NEDD) from 2006 to 2012. The Nationwide Inpatient Sample (NIS) was used to select patients from 2000 to 2013 with proximal humerus fractures treated with open reduction and internal fixation (ORIF), total shoulder arthroplasty (TSA), reverse total shoulder arthroplasty (RSA), and hemiarthroplasty (HSA). RSA and TSA shared the same ICD-9 code until 2010. Results: The incidence of proximal humerus fracture was stable from 2006 to 2012. Hemiarthroplasty was the majority treatment choice for arthroplasty in the early 2000’s. However, in 2008, there was a large decrease in utilization, to 51.3% in 2013. During this period, utilization of TSA greatly increased, coinciding with a large increase of RSA. By 2013, RSA made up 45.1% of arthroplasty procedures. Conclusion: The rate of proximal humerus fracture appears stable, while we observed both an overall increase in operative intervention. RSA appears to be increasingly chosen over HSA for arthroplasty treatment of proximal humerus fractures, an observation more pronounced in older patients. While clinical results appear promising, it is important to remember that most proximal humerus fractures may be treated successfully with conservative management, and rapid adoption of new technology should be watched carefully to ensure appropriate use.

DOI： 10.1080/00913847.2017.1311199

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The University of California, Los Angeles (UCLA) activity scale and the Lower Extremity Activity Scale (LEAS) are the two most-widely used and rigorously developed scales for assessing activity level in patients having joint replacement. However, the two scales are not convertible, and the level of correlation between the two is not clear. Creating a crosswalk between these scales; that is, a concordance table to convert scores from one scale to the other and vice versa, will help compare results from existing studies using either scale, and pool those results for meta-analyses. It also will facilitate pooling data from multiple registries and data sources. Questions/Purpose: To create a crosswalk between the UCLA and the LEAS activity scales for patients having THA or TKA. Methods: Preoperative and 2-year postoperative UCLA and LEAS scores for a cohort of patients undergoing primary TKA or THA at the Hospital for Special Surgery between May 2007 and December 2011 were matched from two registries. The scales were self-administered by patients. Three hundred sixty-four patients having TKAs (67% women; mean age, 67 years) and 403 having THA (66% women; mean age, 66 years) had both scores available. The equipercentile equating method was used to create the crosswalk. The standard response mean was used to assess responsiveness of the converted versus actual UCLA and LEAS scores from baseline to 2 years. Crosswalk validation also included comparing the area under the receiver operating characteristic curve of the actual and converted scores to evaluate their ability to discriminate different levels of function measured using the Hip dysfunction and Osteoarthritis Outcome Score activities of daily living subscale for patients having THA and the Knee injury and Osteoarthritis Outcome Score activities of daily living subscale for patients having TKA. Difference between scores was assessed using the inequality test. Results: For patients having TKA, converted mean scores (UCLA to LEAS, 9.5 ± 3.0; LEAS to UCLA, 4.7 ± 2.1) were not different from the actual scores (UCLA, 4.8 ± 2.1; LEAS, 9.4 ± 2.9). Standard response means for the converted scores (UCLA to LEAS, 0.47; LEAS to UCLA, 0.52) were not different from those of the actual scores (UCLA, 0.48; LEAS, 0.56). The areas under the receiver operating characteristic curve also were not different for actual and converted scores for THA and TKA. Conclusion: We have developed and validated a crosswalk to easily convert UCLA to LEAS scores (and vice versa) for THA and TKA. Reproducing the crosswalk for other lower extremity conditions or surgical procedures may extend its utility to studies assessing activity in patients having these conditions or procedures.

DOI： 10.1007/s11999-016-5130-7

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Attaining stability during total knee arthroplasty (TKA) is essential for a successful outcome. Although traditional constrained total knee prostheses have generally been used in conjunction with intramedullary stems, some devices have been widely used without the use of stems, referred to as non-modular constrained condylar total knee arthroplasty (NMCCK). Questions/Purposes: The aim of this study was to compare revisions rates after total knee replacement with a non-modular constrained condylar total knee (NMCCK) compared to a posterior-stabilized (PS) design. Methods: Between 2007 and 2012, primary PS total knees were compared with NMCCK implants from the same manufacturer. Propensity score matching was performed, and implant survivorship was examined using a Cox proportional hazards model. The cohort consisted of 817 PS knees and 817 NMCCKs matched for patient demographics, surgeon volume, and pre-operative diagnosis. Results: All cause revisions occurred in 11 of 817 (1.35%) in the PS group compared to 28 of 817 (3.43%) in the NMCCK group (p = 0.0168). Excluding revisions for infection and fracture, 8 of 817 (0.98%) PS knees required revision for mechanical failure compared to 18 of 817 (2.20%) NMCCK knees (p = 0.0193). Conclusions: While revisions rates in both cohorts were low, there was a significantly higher revision rate with NMCCKs. Given that cases requiring the use of NMCCK implants are likely more complex than those in which PS implants are used, our findings support the judicious use of NMCCK prostheses.

DOI： 10.1007/s11420-016-9533-5

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Unplanned readmissions have become an important quality indicator, particularly for reimbursement; thus, accurate assessment of readmission frequency and risk factors for readmission is critical. The purpose of this study was to determine (1) the frequency of and (2) risk factors for readmissions for all causes or procedure-specific complications within 30 days after total knee arthroplasty (TKA) as well as (3) the association between hospital volume and readmission rate. Methods: The Statewide Planning and Research Cooperative System (SPARCS) database from the New York State Department of Health was used to identify 377,705 patients who had undergone primary TKA in the period from 1997 to 2014. Preoperative diagnoses, comorbidities, and postoperative complications were determined using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. Readmission was defined as all-cause, due to complications considered by the Centers for Medicare &Medicaid Services (CMS) to be TKA-specific, or due to an expanded list of TKA-specific complications based on expert opinion. Multivariable logistic regression analysis was utilized to determine the independent predictors of readmission within 30 days after surgery. Results: There were 22,076 all-cause readmissions-a rate of 5.8%, with a median rate of 3.9% (interquartile range [Q1, Q3] = 1.1%, 7.2%]) among the hospitals-within 30 days after discharge. Of these, only 11% (0.7% of all TKAs) were due to complications considered to be TKA-related by the CMS whereas 31% (1.8% of all TKAs) were due to TKA-specific complications on the expanded list based on expert opinion. Risk factors for TKA-specific readmissions based on the expanded list of criteria included an age of >85 years (odds ratio [OR] = 1.32, 95% confidence interval [CI] = 1.15 to 1.52), male sex (OR = 1.41, 95% CI = 1.34 to 1.49), black race (OR = 1.24, 95% CI = 1.14 to 1.34), Medicaid coverage (OR = 1.40, 95% CI = 1.26 to 1.57), and comorbidities. Several comorbid conditions contributed to the all-cause but not the TKAspecific readmission risk. Very low hospital volume (<90 cases per year) was associated with a higher readmission risk. Conclusions: The frequency of readmissions for TKA-specific complications was low relative to the frequency of all-cause readmissions. Reasons for hospital readmission are multifactorial and may not be amenable to simple interventions. Health-care-quality measurement of readmission rates should be calculated and risk-adjusted on the basis of procedurespecific criteria. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.16.00874

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Introduction: Bone morphogenetic protein (BMP) is considered off-label when used to augment spinal arthrodesis in children and adolescents. There is a paucity of longer-term information on BMP use in this population. The purpose of this study was to determine the rate of BMP utilization in pediatric spinal arthrodesis, assess factors associated with BMP use in this population, and evaluate long-term outcome. Methods: Spinal arthrodeses in patients 18 years and younger performed in New York State between 2004 and 2014 were identified through the Statewide Planning and Research Cooperative System database. All cases had a minimum 1-year follow-up. The primary outcome was revision arthrodesis. The primary outcome, as well as short-term and longer-term complications were identified using time-to-event analysis. Multivariable Cox proportional hazards models were used to assess the association between BMP and outcomes. Results: Of 7312 children and adolescents who underwent spinal arthrodesis, 462 (6.7%) received BMP. Utilization spiked between 2008 and 2010 when (8.6%) of cases received BMP, but subsequently BMP use returned to pre-2008 levels (2004 to 2007: 5.3%; 2011 to 2014: 5.5%). BMP was more likely to be used in children who were older (P=0.027), white and with higher mean family income (P<0.001 for race and income). BMP was more likely to be used for revision surgery, 2 to 3 level fusions, and spondylolisthesis (P<0.001 for all). Revision rates did not differ based on BMP utilization status. Patients receiving BMP did not have increased risk of short-term complications although at 5-year follow-up, BMP was associated with a statistically significant increased risk of mechanical complications (hazard ratio 1.48; 95% confidence interval, 1.02-2.14). Conclusions: Off-label use of BMP for pediatric spinal arthrodesis increased until 2008 and now appears to be decreasing. Racial/ethnic minorities and lower socioeconomic status patients are less likely to receive BMP. The rate of revision after spinal arthrodesis does not differ between those treated with and without BMP. Further long-term studies are required to delineate appropriate guidelines for BMP utilization in children. Level of Evidence: Level III.

DOI： 10.1097/BPO.0000000000000915

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Study Design. A retrospective state database analysis. Objective. The aim of this study was to describe the epidemiology and complications of as well as indications for primary isolated atlantoaxial fusion. Summary of Background Data. Atlantoaxial fusion involves unique indications, techniques, and complications. There is limited epidemiologic literature focused specifically on this procedure. Methods. New York's Statewide Planning and Research Cooperative System database, an all-payer hospitalization reporting system, was queried to identify all patients undergoing primary isolated atlantoaxial fusion in the state from 1997 to 2012. Demographic and clinical data were extracted and analyzed. United States Census Bureau figures were used to calculate population-adjusted surgical rates. Results. One thousand five hundred fifty-nine patients underwent isolated primary atlantoaxial fusion during the study period. The overall population-adjusted annual surgical rate did not change significantly over time. By 2012, individuals aged-70 years had the highest incidence of surgery [2.37 per 100,000 population; 95% confidence interval (95% CI) 1.68-3.07]. Medicare was the most common payer (44.0% of claims). Approximately 85% of patients had a Charlson/Deyo Comorbidity Index of zero or one. Over time, a significantly lower proportion of atlantoaxial fusions were attributable to rheumatic disease, and a significantly higher proportion were due to fracture. By 2012, management of fractures was the most common indication for C1-C2 fusion (44.1% of cases). Dysphagia or dysphonia occurred after 0.8% of cases, dural tear after 0.3%, infection after 0.5%, and seroma, hematoma, or hemorrhage after 0.5%. In-hospital mortality was 2.7%, of which 76% had fracture as the surgical indication. Conclusion. Isolated atlantoaxial fusions have been performed at a stable, low level over the past 16 years in New York. Although most of these patients are relatively healthy preoperatively, approximately one in 10 experience an in-hospital complication and nearly 3% die in-hospital. Knowledge of these risks will hopefully spur further efforts to minimize them and allow for more accurate counseling of patients and their families.

DOI： 10.1097/BRS.0000000000001603

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background Intraarticular injections are both diagnostic and therapeutic for patients with osteoarthritis. A potential risk of periprosthetic joint infection (PJI) after total hip arthroplasty (THA) may occur from direct inoculation and/or immune suppression by corticosteroids. Large population-level databases were used to evaluate hip injection on the 1-year rate of PJI in patients undergoing primary THA. Methods State-level ambulatory surgery and inpatient databases for Florida and California (2005-2012) were used to identify primary THA patients with 1-year preoperative and postoperative windows to evaluate possible injections or PJI, respectively. Patients were grouped as no injection or as THA performed 6-12 months, 3-6 months, or 0-3 months after injection. Risk adjustment was performed with multivariable regression. Results A total of 173,958 patients were included; 5421 (3.1%) underwent THA after an injection: 1395 (1.1%) of patients after 6-12 months, 1863 patients after 3-6 months, and 2163 (1.2%) after 0-3 months. In the 0-3 month group, PJI was significantly increased at 3 months (1.58%, P = .015), 6 months (1.76%, P = .022), and 1 year (2.04%, P = .031) compared with the noninjection control group (1.04%, 1.21%, and 1.47%, respectively). There were no differences in the 3- to 6-month and 6- to 12-month injection groups. Conclusion There is an increased risk of PJI when THA is performed within 3 months of hip injection. We recommend that patients and their surgeons consider delaying elective THA until 3 months after an injection to avoid this elevated risk of infection.

DOI： 10.1016/j.arth.2016.04.008

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Patient-reported outcome measures (PROMs) are increasingly in demand for outcomes evaluation by hospitals, administrators, and policymakers. However, assessing total hip arthroplasty (THA) through such instruments is challenging because most existing measures of hip health are lengthy and/or proprietary. Questions/purposes: The objective of this study was to derive a patient-relevant short-form survey based on the Hip disability and Osteoarthritis Outcome Score (HOOS), focusing specifically on outcomes after THA. Methods: We retrospectively evaluated patients with hip osteoarthritis who underwent primary unilateral THA and who had completed preoperative and 2-year postoperative PROMs using our hospital’s hip replacement registry. The 2-year followup in this population was 81% (4308 of 5351 patients). Of these, 2371 completed every item on the HOOS before surgery and at 2 years, making them eligible for the formal item reduction analysis. Through semistructured interviews with 30 patients, we identified items in the HOOS deemed qualitatively most important to patients with hip osteoarthritis. The original HOOS has 40 items, the four quality-of-life items were excluded a priori, five were excluded for being redundant, and one was excluded based on patient-relevance surveys. The remaining 30 items were evaluated using Rasch modeling to yield a final six-item HOOS, Joint Replacement (HOOS, JR), representing a single construct of “hip health.” We calculated HOOS, JR scores for the Hospital for Special Surgery (HSS) cohort and validated this new score for internal consistency, external validity (versus HOOS and WOMAC domains), responsiveness to THA, and floor and ceiling effects. Additional external validation was performed using calculated HOOS, JR scores in collaboration with the Function and Outcomes Research for Comparative Effectiveness in Total Joint Replacement (FORCE-TJR) nationally representative joint replacement registry (n = 910). Results: The resulting six-item PROM (HOOS, JR) retained items only from the pain and activities of daily living domains. It showed high internal consistency (Person Separation Index, 0.86 [HSS]; 0.87 [FORCE]), moderate to excellent external validity against other hip surveys (Spearman’s correlation coefficient, 0.60–0.94), very high responsiveness (standardized response means, 2.03 [95% CI, 1.84–2.22] [FORCE]; and 2.38 [95% CI, 2.27–2.49] [HSS]), and favorable floor (0.6%–1.9%) and ceiling (37%–46%) effects. External validity was highest for the HOOS pain (Spearman’s correlation coefficient, 0.87 [95% CI, 0.86–0.89] [HSS]; and 0.87 [95% CI, 0.84–0.90] [FORCE]) and HOOS activities of daily living (Spearman’s correlation coefficient, 0.94 [95% CI, 0.93–0.95] [HSS]; and 0.94 [95% CI, 0.93–0.96] [FORCE]) domains in the HSS validation cohort and the FORCE-TJR cohort. Conclusions: The HOOS, JR provides a valid, reliable, and responsive measure of hip health for patients undergoing THA. This short-form PROM is patient relevant and efficient. Level of Evidence: Level III, diagnostic study.

DOI： 10.1007/s11999-016-4718-2

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Medicare is rapidly moving toward using patient-reported outcome measures (PROMs) for outcomes assessment and justification of orthopaedic and other procedures. Numerous measures have been developed to study knee osteoarthritis (OA); however, many of these surveys are long, disruptive to clinic flow, and result in incomplete data capture and/or low followup rates. The Knee injury and Osteoarthritis Outcome (KOOS) physical function short-form (KOOS-PS), while shorter, ignores pain, which is a primary concern of patients with advanced knee OA. Questions/purposes: Our objective was to derive and validate a short-form survey focused on the patient with end-stage knee OA undergoing TKA. Methods: Using our hospital’s knee replacement registry, we retrospectively identified 2291 patients with knee OA who underwent primary unilateral TKA and had completed preoperative and 2-year postoperative PROMs. We assessed 30 items from the 42-item KOOS that were quantitatively most difficult for patients to perform before TKA and qualitatively most relevant to patients with end-stage knee OA. Rasch analysis identified the KOOS, JR, a seven-item instrument, representing a single dimension, which we define as “knee health” because it reflects aspects of pain, symptom severity, and activities of daily living (ADL) including movements or activities that are directly relevant and difficult for patients with advanced knee OA. We assessed the internal consistency, external validity (versus KOOS and WOMAC domains), responsiveness, and floor and ceiling effects of the KOOS, JR. External validation was performed using calculated KOOS, JR scores in collaboration with a nationally representative joint replacement registry, the Function and Outcomes Research for Comparative Effectiveness in Total Joint Replacement (FORCE-TJR). Results: Internal consistency for the KOOS, JR was high (Person Separation Index, 0.84; and 0.85 [FORCE]), external validity against other validated knee surveys was excellent (Spearman correlation coefficient, ρ 0.54–0.91), particularly for the KOOS pain (ρ 0.89 [95% CI, 0.88–0.91] Hospital for Special Surgery [HSS]; and 0.91 [95% CI, 0.90–0.93] [FORCE]) and KOOS ADL (ρ 0.87 [95% CI, 0.85–0.88] [HSS]; and 0.84 [95% CI, 0.81–0.87] [FORCE]). The KOOS, JR responsiveness (standardized response means, 1.79 [95% CI, 1.70–1.88] [HSS]; and 1.70 [95% CI, 1.54–1.86] [FORCE]) was high and floor 0.4–1.2%) and ceiling (18.8–21.8%) effects were favorable. Conclusions: The new short knee PROM, the KOOS, JR, provides a single score representing “knee health” as it combines pain, symptoms, and functional limitations in a single score. This short-form PROM is patient-relevant and efficient. Level of Evidence: Level III, diagnostic study.

DOI： 10.1007/s11999-016-4719-1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The rate of total ankle arthroplasty (TAA) is increasing in the United States as its popularity and indications expand. There currently is no national joint registry available to monitor outcomes, and few studies have addressed the challenges faced with TAA. The purpose of this study was to evaluate the incidence, complications, and survival rates associated with TAA using a large statewide administrative discharge database. Individuals who underwent primary TAA from 1997 to 2010 were identified in the Statewide Planning and Research Cooperative System database from the New York State Department of Health. The age, sex, comorbidities, state of residence, primary diagnosis, and readmissions within 90 days were analyzed for patients with an ICD-9- CM procedure code of 81.56 (TAA). Failure of a TAA implant was defined as revision, tibiotalar arthrodesis, amputation, or implant removal. During the 14-year period, 420 patients underwent 444 TAAs (mean patient age of 61 years, 59% women, mean Charlson-Deyo comorbidity score of 0.45, and 86% New York State residents). The primary diagnosis was 37.4% osteoarthritis, 34.3% traumatic arthritis, and 15.5% rheumatoid arthritis. Surgery for failure was associated only with a younger age (56.5 vs 62 years, P=.005). The rate of subsequent failure procedures following TAAs performed in New York State was 13.8%. The incidence of TAAs is steadily increasing. The overall survival rate in New York State is better than rates reported in other national registries, but it is not yet comparable to those of hip and knee replacements.

DOI： 10.3928/01477447-20160427-12

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Despite declines in both the incidence of and mortality following hip fracture, there are racial and socioeconomic disparities in treatment access and outcomes. We evaluated the presence and implications of disparities in delivery of care, hypothesizing that race and community socioeconomic characteristics would influence quality of care for patients with a hip fracture. Methods: We collected data fromthe New York State Department of Health Statewide Planning and Research Cooperative System (SPARCS), which prospectively captures information on all discharges from nonfederal acute-care hospitals in New York State. Records for 197,290 New York State residentswho underwent surgery for a hip fracture between 1998 and 2010 in New York State were identified from SPARCS using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. Multivariable regression models were used to evaluate the association of patient characteristics, social deprivation, and hospital/surgeon volume with time from admission to surgery, in-hospital complications, readmission, and 1-year mortality. Results: After adjusting for patient and surgery characteristics, hospital/surgeon volume, social deprivation, and other variables, black patients were at greater risk for delayed surgery (odds ratio [OR] = 1.49; 95% confidence interval [CI] = 1.42, 1.57), a reoperation (hazard ratio [HR] = 1.21; CI = 1.11, 1.32), readmission (OR = 1.17; CI = 1.11, 1.22), and 1-year mortality (HR = 1.13; CI = 1.07, 1.21) than white patients. Subgroup analyses showed a greater risk for delayed surgery for black and Asian patients compared with white patients, regardless of social deprivation. Additionally, there was a greater risk for readmission for black patients compared with white patients, regardless of social deprivation. Compared with Medicare patients,Medicaid patients were at increased risk for delayed surgery (OR = 1.17; CI = 1.10, 1.24) whereas privately insured patients were at decreased risk for delayed surgery (OR = 0.77; CI = 0.74, 0.81), readmission (OR = 0.77; CI = 0.74, 0.81), complications (OR = 0.80; CI = 0.77, 0.84), and 1-year mortality (HR = 0.80; CI = 0.75, 0.85). Conclusions: There are race and insurance-based disparities in delivery of care for patients with hip fracture, someof which persist after adjusting for social deprivation. In addition to investigation into reasons contributing to disparities, targeted interventions should be developed to mitigate effects of disparities on patients at greatest risk. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.15.00676

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose To use population-level data to (1) evaluate the conversion rate of total hip arthroplasty (THA) within 2 years of hip arthroscopy and (2) assess the influence of age, arthritis, and obesity on the rate of conversion to THA. Methods We used the State Ambulatory Surgery Databases and State Inpatient Databases for California and Florida from 2005 through 2012, which contain 100% of patient visits. Hip arthroscopy patients were tracked for subsequent primary THA within 2 years. Out-of-state patients and patients with less than 2 years follow-up were excluded. Multivariate analysis identified risks for subsequent hip arthroplasty after arthroscopy. Results We identified 7,351 patients who underwent hip arthroscopy with 2 years follow-up. The mean age was 43.9 ± 13.7 years, and 58.8% were female patients. Overall, 11.7% of patients underwent THA conversion within 2 years. The conversion rate was lowest in patients aged younger than 40 years (3.0%) and highest in the 60- to 69-year-old group (35.0%) (P <.001). We found an increased risk of THA conversion in older patients and in patients with osteoarthritis or obesity at the time of hip arthroscopy. Patients treated at high-volume hip arthroscopy centers had a lower THA conversion rate than those treated at low-volume centers (15.1% v 9.7%, P <.001). Conclusions Hip arthroscopy is performed in patients of various ages, including middle-aged and elderly patients. Older patients have a higher rate of conversion to THA, as do patients with osteoarthritis or obesity. Level of Evidence Level III, retrospective comparative study.

DOI： 10.1016/j.arthro.2015.10.002

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The goal of elective orthopedic surgery is to return patients to their expected level of activity without an increased incidence of postoperative complications. The first step is identifying patient and/or surgical characteristics responsible for these complications. Questions/Purposes: This study sought to identify predictors of a step-up in medical care after non-ambulatory elective orthopedic surgery. Methods: At a single specialty orthopedic hospital, we identified all in-hospital postoperative patients who were transferred to a higher level of medical care ((PACU) post-anesthesia care unit). The characteristics of both transferred and non-transferred patients were compared. A model was built which incorporated predictors of return to a higher level of care. Results: During a 1-year period, 155 of 7967 patients (1.95%) required transfer to the PACU within 5 days of surgery. Cardiac complications were the major reason for transfer (50.3%), followed by pulmonary (11.0%) and neurological complications (9.7%). Patients who returned to the PACU were older, had more Exlihauser comorbidities, and had obstructive sleep apnea (OSA). In a model adjusting for all patient characteristics: age, American Society of Anesthesiologists (ASA) status, congestive heart failure (CHF), the Charlson comorbidity index and OSA predicted return to the PACU. Conclusions: In an elderly population with multiple comorbidities undergoing elective common major orthopedic procedures, approximately 2% of patients required readmission to the PACU. The most common problems requiring this step-up in care were cardiac and pulmonary, which resulted in an increased length of hospital stay. Patients with OSA and multiple comorbidities undergoing total knee arthroplasty carry an increased risk for postoperative complications.

DOI： 10.1007/s11420-015-9467-3

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Limited data exist on long-term revision rates following cervical spine arthrodeses. The purposes of this study were to define reoperation rates after primary cervical arthrodeses and to identify risk factors for revisions. Methods: New York State's all-payer health-care database was queried to identify all primary subaxial cervical arthrodeses occurring in the 16 years from 1997 through 2012. A total of 87,042 patients were included in the study cohort. Demographic information was extracted. Patients' preoperative medical comorbidities, surgical indications, and operative approaches were assembled using codes from the ICD-9-CM (International Classification of Diseases, Ninth Revision, Clinical Modification). The cohort was followed to revision surgical procedures, death, or the end of the study period. All subsequent contiguous spinal arthrodeses, including in the subaxial cervical spine, were considered revisions. The overall revision risk and the risk associated with various preoperative characteristics, surgical indications, and operative approaches were assessed using a Cox proportional hazard model. Results: During the study period, 6,721 patients (7.7%) underwent revision. The median time to revision was 24.5 months. The probability of undergoing at least one revision by 192 months was 12.6%. Arthrodeses performed via anterior-only approaches had a significantly higher probability of revision (p < 0.001) at 13.4% (95% confidence interval [95% CI], 12.9% to 13.9%) than those performed via posterior approaches at 7.4% (95% CI, 6.6% to 8.4%) or circumferential (anterior and posterior) approaches at 5.2% (95% CI, 4.0% to 6.8%). This relationship persisted in multivariate analysis; compared with anterior surgical procedures, there was a significantly lower risk of revision (p < 0.001) for posterior surgical approaches at a hazard ratio of 0.76 (95% CI, 0.69 to 0.84) and circumferential approaches at a hazard ratio of 0.53 (95% CI, 0.42 to 0.66). Patient age of 18 to 34 years, white race, insurance status of Workers' Compensation or Medicare, and surgical procedures for spinal stenosis, spondylosis, deformity, and neoplasm were associated with elevated revision risk. Arthrodeses spanning few levels and those performed for fractures had a lower revision risk. Conclusions: Primary subaxial cervical spine arthrodeses had a probability of revision approaching 13% over a 16-year period, with elevated reoperation rates in patients undergoing anterior-only surgical procedures. Age, race, insurance status, surgical indication, and number of spinal levels included in the arthrodesis were also associated with reoperation risk. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.15.00938

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Disparities exist in access to outpatient pediatric orthopaedic care. The purpose of this study was to assess whether disparities also exist in elective pediatric orthopaedic surgical procedures such as implant removal, and to determine which demographic and socioeconomic factors may be associated with differences in treatment. Methods: Children aged 7 to 18 inclusive who sustained femoral shaft fractures between the years 1997 and 2010 were identified in the New York State SPARCS database. Patient age, sex, race/ethnicity, insurance status, education, and poverty were identified. Factors associated with the method of fracture treatment were assessed through multivariate regression analysis. The subset of patients that received internal fixation were followed up until 2011 inclusive for implant removal. Factors associated with implant removal were assessed using a Cox proportional hazards survival analysis (time to implant removal). Results: Of the 3220 closed femoral shaft fractures identified, 2609 (81%) were treated with internal fixation, 9 (0.3%) had open treatment without implants, 203 (6.3%) were treated with external fixation, and 399 (12.4%) with closed methods. Patients with No Fault/Accident insurance by No Fault/Accident insurance were more likely to undergo internal fixation compared with patients with private insurance (P<0.001). Of the 3220 patients, 2572 were included in the implant removal subanalysis. Implant removal was performed in 725 (28.2%) patients. In the multivariate model, patients were more likely to undergo removal if they were younger (P<0.001), white [vs. black (P<0.001), vs. Hispanic (P=0.035), vs. other (P=0.001)], and lived in neighborhoods with less poverty (P=0.016). Insurance status was not a statistically significant predictor of implant removal. Conclusions: There is an association between implant removal and younger age, white race, and higher socioeconomic status in children. Awareness of these disparities should prompt further evaluation of causation, whether it be from lack of evidence-based guidelines for implant removal, surgeon bias, variations in reimbursement, or disparities in access to care. Further study is recommended to better elucidate the indications for implant removal in children and the causes for the disparities identified here.

DOI： 10.1097/BPO.0000000000000494

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Previous studies of racial disparities in total joint replacement, particularly total knee arthroplasty, in the U.S. have predominantly focused on disparities between blacks and whites and were limited to Medicare patients or veterans, populations that are not representative of the entire U.S. population. We sought to study racial disparities in the utilization of total knee arthroplasty, the use of high-volume hospitals, and total knee arthroplasty outcomes, including mortality and complications, using all-payer databases. Methods: We analyzed data from 8 years and 8 racially diverse states in the State Inpatient Databases (SID). Patient race was categorized according to the SID as white, black, Hispanic, Asian, Native American, and mixed race. Both crude and adjusted racial and/or ethnic disparities were evaluated. Results: In comparison with whites (4.65 per 1000 population per year), black (3.90), Hispanic (3.71), Asian (3.89), Native American (4.40), and mixed-race (3.69) populations had lower rates of total knee arthroplasty utilization (p < 0.0001). After risk adjustment, the rate of total knee arthroplasty utilization was significantly lower for blacks (odds ratio [OR] = 0.87 [95% confidence interval (CI), 0.85 to 0.89]; p < 0.0001), Hispanics (OR = 0.76 [95% CI, 0.68 to 0.83]; p < 0.0001), Asians (OR = 0.83 [95%CI, 0.78 to 0.89]; p < 0.0001), Native Americans (OR = 0.87 [95%CI, 0.81 to 0.93]; p < 0.0001), and mixed race (OR = 0.84 [95% CI, 0.79 to 0.90]; p < 0.0001) compared with the rate for whites. Lower rates of total knee arthroplasty utilization for blacks, Hispanics, and mixed-race groups becameworse over the years. Patients fromminority groups were less likely to undergo total knee arthroplasty in high-volume hospitals than were whites. Moreover, the rates of mortality were significantly higher for blacks (OR = 1.52 [95% CI, 1.17 to 1.97]; p = 0.0017), Native Americans (OR = 6.52 [95% CI, 4.63 to 9.17]; p < 0.0001), and mixed-race patients (OR = 4.35 [95% CI, 3.24 to 5.84]; p < 0.0001). Blacks (OR = 1.08 [95% CI, 1.01 to 1.15]; p = 0.01) and mixed-race patients (OR = 1.17 [95% CI, 1.001 to 1.36]; p = 0.04) had higher rates of complications than whites. Conclusions: Minorities had lower rates of total knee arthroplasty utilization but higher rates of adverse health outcomes associated with the procedure, even after adjusting for patient-related and health-care system-related characteristics. Utilization rates were based on overall population as the proportion of the population with osteoarthritis requiring arthroplasty is unknown. Future studies that consider specific patient-level information with psychosocial and behavioral factors are needed. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.15.01009

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Increasing evidence supports the finding that patients undergoing a total knee arthroplasty with high-volume physicians and hospitals achieve better outcomes. Unfortunately, the existing definitions for high-volume surgeons and hospitals are highly variable and entirely arbitrary. The aim of this study was to identify a set of meaningful hospital and surgeon total knee arthroplasty volume thresholds. Methods: Using 289,976 patients undergoing primary total knee arthroplasty from an administrative database, we applied stratum-specific likelihood ratio (SSLR) analysis of a receiver operating characteristic (ROC) curve to generate sets of volume thresholds most predictive of adverse outcomes. The outcomes considered for surgeon volume included 90-day complication and 2-year revision. For hospital volume, we considered 90-day complications and 90-day mortality. Results: SSLR analysis of the ROC curves for 90-day complication and 2-year revision rates by surgeon volume identified four volume categories: 0 to 12, 13 to 59, 60 to 145, and >146 total knee arthroplasties per year. Complication rates decreased significantly (p< 0.05) in progressively higher-volume categories. Revision rates followed a similar pattern, but did not decrease between surgeons performing 60 to 145 arthroplasties per year and those performing >146 arthroplasties per year. SSLR analysis of 90 day complication and 90-day mortality rates by hospital volume also identified four volume categories: 0 to 89, 90 to 235, 236 to 644, and >645 total knee arthroplasties per year. Complication rates decreased significantly (p < 0.05) in progressively higher-volume categories, but the rates did not decrease between hospitals performing 236 to 644 arthroplasties per year and those performing >645 arthroplasties per year. Mortality rates for hospitals with >645 total knee arthroplasties per year were significantly lower (p < 0.05) than those below the threshold. Conclusions: Our study supports the use of SSLR analysis of ROC curves for risk-based volume stratification in total knee arthroplasty volume-outcomes research. SSLR analysis established meaningful volume definitions for low, medium, high, and very high-volume total knee arthroplasty surgeons and hospitals. This should help patients, surgeons, hospitals, and policymakers to make decisions with regard to the optimal delivery of total knee arthroplasty. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.15.01365

記述言語：英語   掲載種別：研究論文（学術雑誌）  

We sought to determine if prolonged length of stay (pLOS) is an accurate measure of quality in total hip and knee arthroplasty (THA and TKA). Coded complications and pLOS for 5967 TKA and 4518 THA patients in our hospital discharged between 2009 and 2011 were analyzed. Of 727 patients with pLOS, only 170 also had a complication, yielding a sensitivity of 41.4% (95% CI: 36.7, 46.2) with a positive predictive value (PPV) of just 23.4% (95% CI: 20.3, 26.4). Specificity (94.5% [95% CI: 94.0, 94.9]) and negative predictive value (NPV) (97.5% [95% CI: 97.2, 97.8]) were high, due to the large number of patients without complications or pLOS. This suggests that risk-adjusted pLOS is an inadequate measure of patient safety in primary THA and TKA.

DOI： 10.1016/j.arth.2015.05.019

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Whereas most proximal humerus fractures are treated nonoperatively, complex 3- and 4-part fractures may require shoulder arthroplasty. Hemi-shoulder arthroplasty (HSA) has been the standard treatment, but recently there has been discussion and utilization of reverse total shoulder arthroplasty (RTSA) as a viable treatment option. This study evaluated the national utilization of RTSA and HSA for proximal humerus fractures and compared patient and hospital characteristics associated with each procedure. Methods: This study used the Nationwide Inpatient Sample database for 2011, which allows national estimates of inpatient hospital discharges. Patients were selected by diagnosis and procedure codes to identify those who underwent RTSA or HSA for treatment of proximal humerus fractures. Patient and hospital characteristics associated with each procedure as well as in-hospital complication rates were identified. Results: An estimated 7714 patients with proximal humerus fractures were selected, 27.4% of whom were treated with RTSA. Except for increased age, patient characteristics were similar between groups, as were complication rates. RTSA was more likely to be performed over HSA in small, rural, nonteaching hospitals and also in those that had already adopted and performed a high volume of RTSA procedures for other diagnoses. Conclusions: Although HSA remains the most common arthroplasty choice for proximal humerus fractures, RTSA is becoming widely used. Patient characteristics and complications were similar between the 2 procedures, and as clinical evidence appears to show improved outcomes with RTSA, it is likely that acceptance of RTSA will continue to grow.

DOI： 10.1016/j.jse.2015.03.018

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Despite the success of total knee arthroplasty (TKA), numerous studies report that nearly one in five patients who underwent TKA was unsatisfied with their outcome. The purpose of our study was to identify the preoperative factors predictive of satisfaction following well-performed TKA. Using improvement in patient-reported outcomes less than the minimally clinically important change as an indicator of dissatisfaction in a cohort of primary TKA patients, we found that patients with greater preoperative pain and disability with less severe degradation in health-related quality of life were more likely to be satisfied with the result of TKA. Balancing severity of symptoms and impact to quality of life is important when counseling patients considering TKA.

DOI： 10.1016/j.arth.2015.01.039

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Assessment of clinical outcomes and patient quality of life after total hip arthroplasty continues to grow in importance with the focus on how bearing surfaces affect long-term survival, wear, and cost. Further, as quality measures have become incorporated into reimbursement, there is a need to quantify factors which may influence these outcomes. Currently, there is a paucity of literature regarding the effects of the femoral head composition on clinical outcomes or quality of life. Questions/Purposes: We sought to determine if any difference in quality of life measures could be detected in patients treated with total hip replacement implanted with cobalt-chrome (CoCr) versus ceramic femoral heads at 2-year follow-up. Methods: We compared the hip disability and osteoarthritis outcome score (HOOS) and EuroQOL (EQ5D) scores of a matched set of patients that underwent primary total hip arthroplasty with highly cross-linked polyethylene (HXLPE) and a single implant system consisting of either a metal or a ceramic femoral head. Results: Clinical outcomes and quality of life improved for both groups after hip replacement surgery. Patients with a ceramic head showed greater improvement than those with a metal head in HOOS pain and EQ5D VAS scores by a statistically significant margin (p = 0.0417 and 0.019, respectively), but the differences between the HOOS and EQ5D VAS scores (3.4 and 0.04, respectively) do not demonstrate a clinically significant difference. Conclusions: We found that the femoral head composition has no effect on clinical outcomes or patient quality of life at 2 years.

DOI： 10.1007/s11420-015-9433-0

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Healthcare reorganization and bundled payment schemes have resulted in increased patient travel distances in orthopedics. Travel distance has been previously associated with increased complication risk but has yet to be studied in orthopedics. We analyzed the impact of patient travel distance on short-term complications. We reviewed 38,887 TJAs performed between 2008 and 2011 and identified 1606 complications in 1110 procedures. There was no significant association between complication risk and patient travel distance. Complication risk was associated with age, ASA class, Medicare and Medicaid status (P<. 0.0001 for all). Regional centers of excellence appear to be a viable model in healthcare reorganization however continued attention should be paid to attenuating the individual patient factors associated with complication at these institutions.

DOI： 10.1016/j.arth.2015.01.015

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The foot and ankle outcome score (FAOS) has been evaluated for many conditions of the foot and ankle. We evaluated its construct validity in 136 patients with osteoarthritis of the ankle, its content validity in 37 patients and its responsiveness in 39. Data were collected prospectively from the registry of patients at our institution. All FAOS subscales were rated relevant by patients. The Pain, Activities of Daily Living, and Quality of Life subscales showed good correlation with the Physical Component score of the Short-Form-12v2. All subscales except Symptoms were responsive to change after surgery. We concluded that the FAOS is a weak instrument for evaluating osteoarthritis of the ankle. However, some of the FAOS subscales have relative strengths that allow for its limited use while we continue to seek other satisfactory outcome instruments.

DOI： 10.1302/0301-620X.97B5.33940

記述言語：英語   掲載種別：研究論文（学術雑誌）  

We used a large prospective institutional registry to determine if there is a 'safe zone' that exists for acetabular component position within which the risk of hip dislocation is low and if other patient and implant factors affect the risk of hip dislocation. Patients who reported a dislocation event within six months after hip arthroplasty surgery were identified, and acetabular component position was measured with anteroposterior radiographs. The frequency of dislocation was 2.1% (147 of 7040 patients). No significant difference was found in the number of dislocated hips among the radiographic zones (± 5°, ± 10°, ± 15° boundaries). Dislocators < 50. years old were less active preoperatively than nondislocators (P=0.006). Acetabular component position alone is not protective against instability.

DOI： 10.1016/j.arth.2014.07.009

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Regionalization of total joint arthroplasty (TJA) to high volume hospitals (HVHs) may affect access to care and complication risk. Using administrative data, 2,560,314 patients who underwent primary total hip or knee arthroplasty from 1991 to 2006 were categorized by whether an HVH (>. 200 annual TJAs) was available locally. Associations among patient characteristics, hospital utilization, and in-hospital complications were estimated using regression modeling. The complication risk was higher (Odds Ratio 1.18 [95% CI: 1.16, 1.20]) if patients went to a local low volume hospital. Black and Medicaid patients were more likely to utilize the local low volume hospital than a local HVH. Utilizing a local HVH is associated with lower complication risks. However, patients from vulnerable groups were less likely to utilize these patterns.

DOI： 10.1016/j.arth.2014.08.017

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The substantial increase in the utilization of shoulder arthroplasty in the United States during the past decade is partly attributable to the growing acceptance of reverse shoulder arthroplasty (RSA). This study compared the national utilization of and indications for shoulder hemiarthroplasty, total shoulder arthroplasty (TSA), and RSA. Methods: The Nationwide Inpatient Sample was used to identify shoulder arthroplasty procedures performed in the United States in 2011. Indicating diagnoses, demographics, and hospital characteristics were identified for each shoulder arthroplasty procedure. Multivariable regression identified factors associated with long hospital stays. Results: An estimated 66,485 shoulder arthroplasty procedures were identified (33% RSA, 44% TSA, and 23% hemiarthroplasty). Common diagnoses for RSA were rotator cuff tear and arthritis (80%) and proximal humerus fracture (10%). TSA was performed for osteoarthritis in 93% of cases. Hemiarthroplasty was performed for osteoarthritis (45%) and proximal humerus fracture (38%). One quarter of proximal humerus fractures treated with arthroplasty received RSA compared with 69.8% that underwent hemiarthroplasty. Mortality occurred in 0.08% of patients with atraumatic diagnoses but in 0.53% of patients with proximal humerus fractures (. P<.001). Older patients with comorbidities often had longer hospital stays, as did those with government insurance. Conclusions: RSAs accounted for one third of all shoulder arthroplasty procedures in the United States in 2011. Whereas the majority of RSAs are performed for rotator cuff tear arthropathy, one quarter of proximal humerus fractures are treated with RSA, suggesting the strong uptake of this relatively new procedure in the United States.

DOI： 10.1016/j.jse.2014.08.026

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Methods: We developed four computerized scenarios for all combinations of race (white or black) and sex (male or female) for otherwise similar patients with end-stage knee osteoarthritis. Patients gave an orthopaedic history of 2 years worsening pain with decreased functional status and failure of oral antiinflammatory medications and corticosteroid intraarticular injections. Orthopaedic surgeons attending the 2012 annual meetings of the New York State Society of Orthopaedic Surgeons and American Association of Hip and Knee Surgeons were recruited for the study. Surgeons passing an open recruitment table at each meeting were asked to participate. Of the 1111 surgeons in attendance at either meeting, 113 (10.2%) participated in the study. All participants viewed the “control” patient’s story (white male) and were randomized to view one of the three “experimental” scenarios (white female, black male, black female). After viewing each scenario, the participants were anonymously asked whether they would recommend TKA. An a priori power analysis showed that 112 participants were needed to detect a 15% difference in the likelihood of recommending surgery for white versus nonwhite patients in the test scenarios evaluated with 90% power at a level of significance of 0.05.
Questions/purpose: Using an experimental approach with standardized patient scenarios, we sought to evaluate surgeon recommendations regarding TKA, specifically to determine whether recommendations for TKA are influenced by (1) patient race, and (2) patient sex.
Background: Prior investigations have suggested that physician-related factors may contribute to differential use of TKA among women and ethnic minorities. We sought to evaluate the effect of surgeon bias on recommendations for TKA.
Results: Of the 39 surgeons who viewed the white male plus black female scenario, there were 33 (85%) concordant responses (TKA offered to both patients) and six discordant responses (TKA offered to only one of the patients), with no effect of patient race and sex (p = 0.99). Of the 37 surgeons who viewed the white male plus black male scenario, there were 33 (89%) concordant responses and four discordant responses, with no effect of patient race (p = 0.32). Of the 37 surgeons who viewed the white male plus white female scenario, there were 30 (77%) concordant responses and seven discordant responses, with no effect of patient sex (p = 0.71).
Conclusion: After orthopaedic surgeons viewed video scenarios of patients with end-stage knee osteoarthritis, patient race and sex were not associated with a different likelihood of a surgical recommendation. Our findings support the notion that patient race and sex may be less influential on decision making when there are strong clinical data to support a decision. Physician bias may have a greater effect on decision making in situations where the indications for surgery are less clear.

DOI： 10.1007/s11999-014-4003-1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

OBJECTIVES: We aimed to assess the long-term safety and tolerability of imatinib in diffuse cutaneous systemic sclerosis (dcSSc).
METHODS: In this open-label, single-arm, extension-phase clinical trial, patients continued imatinib for 24 months following 12 months of initial treatment.
RESULTS: Seventeen patients were enrolled. Forty of 92 adverse events (AE) and 0/6 serious (S) AEs were possibly related to medication. The MRSS decreased from a median of 21 to 16, (p=0.002).
CONCLUSIONS: This study demonstrates long-term safety and tolerability of imatinib in a substantial proportion of patients with dcSSc. This is important in evaluating the relevance of this therapy in a chronic disease such as SSc.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Conflicting evidence exists with regard to weight loss after total hip arthroplasty or total knee arthroplasty. The purposes of this study were to determine whether patients lose weight after total hip arthroplasty or total knee arthroplasty, whether there are predictors of weight change after total hip arthroplasty or total knee arthroplasty, and whether weight changes after total hip arthroplasty or total knee arthroplasty affect patient-reported outcomes. Methods: Using our institutional registry, we evaluated the two-year change in self-reported body mass indices for all patients who underwent elective, unilateral total hip arthroplasty or total knee arthroplasty for osteoarthritis. A 5% change in body mass index was considered clinically meaningful. Patient-reported outcomes were compared between patients who underwent total hip arthroplasty and those who underwent total knee arthroplasty and between obesity classes, on the basis of whether patients gained, lost, or maintained weight. Results: We reviewed 3893 total hip arthroplasties and 3036 total knee arthroplasties. Of the patients who underwent total joint arthroplasty, 73% (2850 patients) in the total hip arthroplasty group and 69% (2090 patients) in the total knee arthroplasty group demonstrated no change in body mass index. Patients who underwent total knee arthroplasty were more likely to lose weight than patients who underwent total hip arthroplasty. Increasing preoperative obesity correlated with a greater likelihood of weight loss. Patients who underwent total knee arthroplasty and lost weight demonstrated better clinical outcome scores, but weight gain in general was associated with inferior clinical outcomes. Greater body mass index, total knee arthroplasty, and female sex were significant predictors of weight loss (p < 0.05). Better preoperative functional status was significantly associated with a lower likelihood of weight gain (p < 0.05). Conclusions: Most patients maintained their body mass index after total hip arthroplasty or total knee arthroplasty. Female patients, patients with higher preoperative body mass index, and those who underwent total knee arthroplasty were more likely to lose weight after surgery.

DOI： 10.2106/JBJS.N.00232

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: There have been no population-based studies to evaluate the rate of pediatric anterior cruciate ligament (ACL) reconstruction. Purpose: The primary aim of the current study was to determine the yearly rate of ACL reconstruction over the past 20 years in New York State. Secondary aims were to determine the age distribution for ACL reconstruction and determine whether patient demographic and socioeconomic factors were associated with ACL reconstruction. Study Design: Descriptive epidemiology study. Methods: The Statewide Planning and Research Cooperative System (SPARCS) database contains a census of all hospital admissions and ambulatory surgery in New York State. This database was used to identify pediatric ACL reconstructions between 1990 and 2009; ICD-9-CM (International Classification of Diseases, 9 Revision, Clinical Modification) and CPT-4 (Current Procedural Terminology, 4th Revision) codes were used to identify reconstructions. Patient sex, age, race, family income, education, and insurance status were assessed. Results: The rate of ACL reconstruction per 100,000 population aged 3 to 20 years has been increasing steadily over the past 20 years, from 17.6 (95% confidence interval [CI], 16.4-18.9) in 1990 to 50.9 (95% CI, 48.8-53.0) in 2009. The peak age for ACL reconstruction in 2009 was 17 years, at a rate of 176.7 (95%CI, 160.9-192.5). In 2009, the youngest age at which ACL reconstruction was performed was 9 years. The rate of ACL reconstruction in male patients was about 15% higher than in females, and ACL reconstruction was 6-fold more common in patients with private health insurance compared with those enrolled in Medicaid. Conclusion: This study is the first to quantify the increasing rate of ACL reconstructions in the skeletally immature. Only ACL reconstructions were assessed, and it is possible that some ACL tears in children are not diagnosed or are treated nonoperatively. The rate of ACL tears in New York State is likely higher than the rate of reconstructions reported in this study. Significance: This study quantifies the increasing rate of ACL reconstruction in the skeletally immature and suggests that there may be some disparities in care based on insurance status.

DOI： 10.1177/0363546513518412

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Patellar crepitation and clunk (PCC) is an important and modifiable complication of total knee arthroplasty (TKA). We calculated the incidence of PCC using a modern fixed-bearing TKA prosthesis, assessed whether PCC is associated with knee range of motion, and determined if there were any radiographic variables associated with the development of PCC in this prosthetic design. Five hundred seventy primary TKAs were evaluated after a mean follow-up of 24. months (range 12-81). Thirty-four knees developed PCC (6%); 6 required arthroscopic debridement. With each degree increase in the flexion angle, the likelihood of developing PCC increased by 4.2%. The incidence of PCC was low but increased with postoperative flexion ≥ 110°. No radiographic parameters were associated with the development of PCC.

DOI： 10.1016/j.arth.2013.08.008

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective: Rising anti-double-stranded (ds) DNA titers have been shown by some, but not all, studies to be predictive of disease flares in systemic lupus erythematosus (SLE). We hypothesized that a rapid and substantial rise in anti-dsDNA titer (anti-dsDNA surge) would be a good predictor of a clinically important SLE flare. Methods: A matched case-control study was conducted in an academic rheumatology practice setting. Our primary endpoint was the occurrence of a severe SELENA-SLEDAI (SS) flare within six months of an anti-dsDNA surge, and secondary endpoints were mild/moderate SS flares, as well as BILAG A and B renal flares. Cases were identified as those patients whose disease course included a surge of anti-dsDNA, defined as an increase of anti-dsDNA titer by the Crithidia luciliae immunofluorescence (CLIF) assay from 0 to 3+/4+, or from 1+ to 4+, within a period of less than 12 months. The date of the anti-dsDNA surge was defined as Day 0. Two control SLE patients were identified for each case and were matched for age, sex, race, and visit date closest to case Day 0, but without an anti-dsDNA surge. Logistic regression models were used to detect associations between anti-dsDNA surges and severe SS flares. Result: A higher proportion of cases, compared to controls, experienced a severe SS flare within six months of Day 0 (OR 6.3 (95% confidence intervals 2.0-19.9), p=0.02). Associations with all flares and hospitalizations for flares were also observed. However, an anti-dsDNA surge was not predictive of a renal flare. Conclusion: An anti-dsDNA surge predicts the subsequent development of a severe SS flare within six months. Physicians should closely monitor such patients and treat promptly at the first sign of clinical activity.

DOI： 10.1177/0961203313515763

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Adverse local tissue reactions (ALTR) around metal-on-metal (MOM) hip arthroplasties are increasingly being recognized as a cause of failure. These reactions may be associated with intraoperative tissue damage and complication rates as high as 50% after revision. Although MRI can identify ALTR in MOM hips, it is unclear whether the MRI findings predict those at revision surgery. Questions/purposes: We therefore (1) identified which MRI characteristics correlated with histologically confirmed ALTR (using the aseptic lymphocytic vasculitis-associated lesions [ALVAL] score) and intraoperative tissue damage and (2) developed a predictive model using modified MRI to detect ALVAL and quantify intraoperative tissue damage. Methods: We retrospectively reviewed 68 patients with failed MOM hip arthroplasties who underwent preoperative MRI and subsequent revision surgery. Images were analyzed to determine synovial volume, osteolysis, and synovial thickness. The ALVAL score was used to grade tissue samples, thus identifying a subset of patients with ALTR. Intraoperative tissue damage was graded using a four-point scale. Random forest analysis determined the sensitivity and specificity of MRI characteristics in detecting ALVAL (score ≥ 5) and intraoperative tissue damage. Results: Maximal synovial thicknesses and synovial volumes as determined on MRI correlated with the ALVAL score and were higher in cases of severe intraoperative tissue damage. Our MRI predictive model showed sensitivity and specificity of 94% and 87%, respectively, for detecting ALVAL and 90% and 86%, respectively, for quantifying intraoperative tissue damage. Conclusions: MRI is sensitive and specific in detecting ALVAL and tissue damage in patients with MOM hip implants. MRI can be used as a screening tool to guide surgeons toward timely revision surgery. Level of Evidence: Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

DOI： 10.1007/s11999-013-2788-y

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The aims of this study were to determine the rates of in-hospital complications, discharge disposition, and length of stay for patients with varying degrees of obesity. We identified 4718 patients who underwent TKA between 2007 and 2010. After adjusting for age, sex, race, education, Deyo-Charlson comorbidity index, insurance, and discharge disposition, obese patients were more likely to develop any in-hospital complication (6.4% vs. 4.8%, respectively; P= 0.0097; OR = 1.5). When analyzing specific in-hospital complications, obese patients were more likely to suffer urinary tract infections (P= 0.0029). They were also more likely to be discharged to a rehabilitation facility (P= 0.001). There was no significant difference in other postoperative complications. In summary, obese patients undergoing primary TKA are at increased risk for all-cause in-hospital complications and urinary tract infections and are more likely to be discharged to a rehabilitation facility.

DOI： 10.1016/j.arth.2014.02.013

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective Although rates of arthroplasty have increased dramatically, rates among patients with rheumatoid arthritis (RA) are reported to be decreasing. It is not known if this is also the case among patients with other inflammatory arthritides. This study was undertaken to evaluate rates of arthroplasty due to RA, juvenile idiopathic arthritis (JIA), spondyloarthritis (SpA), and a composite group of patients with inflammatory arthritides (IA), compared to arthroplasty rates among patients without inflammatory or autoimmune conditions. Methods Administrative discharge databases (State Inpatient Databases of the Healthcare Cost and Utilization Project, New York Department of Health Statewide Planning and Research Cooperative System, California Statewide Health Planning and Development) were used to compare rates of knee, hip, and shoulder arthroplasty occurring from 1991 to 2005. Results Of 2,839,325 arthroplasties in 1991-2005, 2.7% were performed in patients with IA. The rate of arthroplasty for noninflammatory conditions doubled (124.5 per 100,000 persons in 1991 versus 247.5 per 100,000 persons in 2005), while the rate for IA remained stable at 5.1 per 100,000. Rates of arthroplasty for RA decreased slightly (4.6 per 100,000 versus 4.5 per 100,000) and those for JIA decreased by nearly 50% (0.22 per 100,000 versus 0.13 per 100,000), but the rate of arthroplasty for SpA increased by nearly 50% (0.22 per 100,000 versus 0.31 per 100,000). Age at the time of arthroplasty increased for patients with RA (mean ± SD 63.4 ± 12.7 years versus 64.9 ± 12.8 years), JIA (30.9 ± 12.2 years versus 36.7 ± 14.9 years), and SpA (54.3 ± 16.1 years versus 60.4 ± 13.9 years). However, the mean age at the time of arthroplasty among non-IA cases decreased (71.5 ± 11.8 years versus 69.0 ± 12.0 years). Conclusion This population-based study is the first to show that arthroplasty rates have decreased significantly among patients with JIA and minimally among patients with RA, and have increased among patients with SpA. The increased age at the time of arthroplasty among patients with JIA and SpA suggests that these patients are increasingly able to defer surgical interventions. Further research is needed to assess the ongoing effect of biologic agents on the need for arthroplasties in patients with IA.

DOI： 10.1002/art.38384

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: The case of a patient with knee valgus and instability due to combined ACL-MCL laxity who underwent lateral opening wedge distal femoral osteotomy (DFO) is presented. The symptoms of instability resolved following the surgery. It was unclear whether the increase in valgus stability was related only to a decrease in valgus moments during stance or also to a medial tensioning effect. We therefore performed a laboratory cadaveric study. The purpose of this study was to examine whether after MCL and ACL sectioning, lateral opening wedge DFO would result in decrease in medial opening under static conditions of valgus stress. Methods: Medial knee opening under valgus load of 9.8 Nm was tested in 8 cadaveric specimens in scenarios of MCL and ACL sectioning and compared before and after performing lateral opening wedge DFO. Results: When the superficial MCL was sectioned, medial knee opening in 30° flexion decreased after lateral opening wedge DFO compared to medial opening before the osteotomy (i.e. from 6.5 ± 0.5° to 5.6 ± 0.5°, p = 0.01). When the superficial MCL, deep MCL, and ACL were all sectioned, medial knee opening in extension decreased after lateral opening wedge DFO compared to medial opening before the osteotomy but this was not significant (i.e. from 6.8 ± 0.5° to 6.1 ± 0.5°, p = n.s.). Conclusion: In superficial MCL-transected knees, medial laxity at 30° of knee flexion decreased after lateral opening wedge DFO. However, the clinical relevance of the laxity decrease observed remains uncertain since the reduction was small in magnitude. Level of evidence: Controlled laboratory study.

DOI： 10.1007/s00167-013-2405-3

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Previous research has demonstrated both greater difficulty in obtaining follow-up appointments and increased likelihood of return visits to the emergency department (ED) for patients with government-funded insurance plans. The purpose of the current study is to determine whether socioeconomic factors, such as race and insurance type, are associated with the frequency of repeat ED visits in pediatric patients with closed fractures. Methods: A review of ED visit data over a 2-year period from a statewide hospital discharge database in New York was conducted. Discharges for patients with a unique person identifier in the database age 17 years and younger were examined for an ICD-9 diagnosis of closed upper or lower extremity fracture. Age, sex, race, and insurance type for patients with a return ED visit within 8 weeks for the same fracture diagnosis were compared with those without a return visit using standard univariate statistical tests and logistic regression analyses. Results: Of the 68,236 visits reviewed, the revisit rate was 0.85%. Patients of nonwhite or unidentified race were significantly more likely to have a revisit than white patients (OR, 1.27; P=0.006). Patients with government-funded insurance were significantly more likely to have a revisit than those without government-funded insurance (OR, 1.55; P<0.001). Patients with private insurance were significantly less likely to have a revisit than those without private insurance (OR, 0.72; P=0.001). Conclusions: Our analysis revealed that nonwhite patients are more likely to return to the ED within 8 weeks for the same fracture diagnosis. Patients with government insurance are 55% more likely to have a revisit, whereas patients with private insurance are 28% less likely to have a revisit. Our results suggest that socioeconomic disparities exist in access to orthopaedic care for closed fractures in a pediatric population. Physicians and policy makers should be mindful of these health care disparities when striving to improve access to care among patients and resource utilization in the ED. Level of evidence: Prognostic level II.

DOI： 10.1097/BPO.0000000000000143

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: An in-depth understanding of risk factors for revision TKA is needed to minimize the burden of revision surgery. Previous studies indicate that hospital and community characteristics may influence outcomes after TKA, but a detailed investigation in a diverse population is warranted to identify opportunities for quality improvement. Questions/purposes: We asked: (1) What is the frequency of revision TKA within 10 years of primary arthroplasty? (2) Which patient demographic factors are associated with revision within 10 years of TKA? (3) Which community and institutional characteristics are associated with revision within 10 years of TKA? Methods: We identified 301,955 patients who underwent primary TKAs in New York or California from 1997 to 2005 from statewide databases. Identifier codes were used to determine whether they underwent revision TKA. Patient, community, and hospital characteristics were analyzed using multivariable regression modeling to determine predictors for revision. Results: The frequency of revision was 4.0% at 5 years after the index arthroplasty and 8.9% at 9-years. Patients between 50 and 75 years old had a lower risk of revision than patients younger than 50 years (hazard ratio [HR], 0.47; 95% CI, 0.44, 0.50). Black patients were at increased risk for needing revision surgery (HR, 1.39; 95% CI, 1.29, 1.49) after adjustment for insurance type, poverty level, and education. Women (HR, 0.82; 95% CI, 0.79, 0.86) and Medicare recipients (HR, 0.82; 95% CI, 0.79, 0.86) were less likely to undergo revision surgery, whereas those from the most educated (HR, 1.09; 95% CI, 1.02, 1.16) and the poorest communities (HR, 1.08; 95% CI, 1.01, 1.15) had modest increases in risk of revision. Mid-volume hospitals (200-400 annual cases) had a reduction of early revision (HR, 0.91; 95% CI, 0.83, 0.99) compared with those performing less than 200 cases annually, whereas higher-volume hospitals (greater than 400 cases) showed little effect compared with low-volume hospitals. Conclusions: Patient, community, and institutional characteristics affect the risk for revision within 10 years of index TKA. These data can be used to develop process improvement and implant surveillance strategies among high-risk patients. Level of Evidence: Level III, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

DOI： 10.1007/s11999-013-3416-6

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective. Revision total hip arthroplasty (THA) is associated with increased cost, morbidity, and technical challenge compared to primary THA. A better understanding of the risk factors for early revision is needed to inform strategies to optimize patient outcomes. Methods. A total of 207,256 patients who underwent primary THA between 1997-2005 in California and New York were identified from statewide databases. Unique patient identifiers were used to identify early revision THA (<10 years from index procedure). Patient characteristics (demographics, comorbidities, insurance type, and preoperative diagnosis), community characteristics (education level, poverty, and population density), and hospital characteristics (annual THA volume, bed size, and teaching status) were evaluated using multivariable regression to determine risk factors for early revision. Results. The probabilities of undergoing early aseptic revision and early septic revision were 4% and <1% at 5 years, respectively. Women were 29% less likely than men to undergo early septic revision (P < 0.001). Patients with Medicaid and Medicare were 91% and 24%, respectively, more likely to undergo early septic revision than privately insured patients (P = 0.01 and P < 0.001, respectively). Hospitals performing <200 THAs annually had a 34% increased risk of early aseptic revision compared to hospitals performing >400 THAs annually (P < 0.001). Conclusion. A number of identifiable factors, including younger age, Medicaid, and low hospital volume, increase the risk of undergoing early revision THA. Patient-level characteristics distinctly affect the risk of revision within 10 years, particularly if due to infection. Our findings reinforce the need for continued investigation of the predictors of early failure following THA.

DOI： 10.1002/acr.22240

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Constrained primary total knee arthroplasty (TKA) can provide stability in the face of incompetent collateral structures or irreconcilable flexion-extension imbalances. However, little is known about its effect on overall knee range of motion (ROM). This study determines whether TKA with increased constraint affects postoperative ROM. Methods: Patients undergoing primary TKA using either posterior stabilized (PS) or constrained condylar knee (CCK) inserts were match-paired based on body mass index, preoperative ROM, and direction and severity of the coronal deformity, yielding 68 pairs. ROM and Knee Society Score (KSS) were obtained preoperatively and at 6. weeks, 4. months, and 1. year. Results: When the 68 matched pairs were considered, all outcome variables related to ROM between the PS and CCK groups at each of the postoperative intervals were similar. Additionally, both the individual items and combined scores of the KSS were similar between groups at all time points. Conclusions: We demonstrate that the use of increased constraint does not affect ROM, relief of pain, or function after TKA. Level of evidence: Level III (retrospective case-controlled study, based on prospectively collected data).

DOI： 10.1016/j.knee.2013.07.002

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Many patients change hospitals for revision total joint arthroplasty (TJA). The implications of changing hospitals must be better understood to inform appropriate utilization strategies. Questions/purposes: (1) How frequently do patients change hospitals for revision TJA? (2) Which patient, community, and hospital characteristics are associated with changing hospitals? (3) Is there an increased complication risk after changing hospitals? Methods: We identified 17,018 patients who underwent primary TJA and subsequent same-joint revision in New York or California (1997-2005) from statewide databases. Medicare was the most common payer (56%) followed by private insurance (31%). We identified patients who changed hospitals for revision TJA and those who experienced in-hospital complications. Patient, community, and hospital characteristics were analyzed to determine predictors for changing hospitals for revision TJA and the effect of changing hospitals on subsequent complications. Results: Thirty percent of patients changed hospitals for revision. Older patients were less likely to change hospitals (odds ratio [OR], 0.84; 95% confidence interval [CI], 0.73-0.96); no other patient characteristics were associated with changing hospitals. Patients who had index TJA at the highest-volume hospitals were less likely to change hospitals (OR, 0.52; 95% CI, 0.48-0.57). Overall, changing hospitals was associated with higher complication risk (OR, 1.19; 95% CI, 1.03-1.39). Changing to a lower-volume hospital (6% of patients undergoing revision TJA) was associated with a higher risk of complications (OR, 1.36; 95% CI, 1.05-1.74). A post hoc number needed-to-treat analysis indicates that 234 patients would need to be moved from a lower volume hospital to a higher volume hospital to avoid one overall complication event after revision TJA. Conclusions: Although the complication risk was higher if changing hospitals, this finding was sensitive to the type of change. Our findings build on the existing evidence of a volume-outcomes benefit for revision TJA by examining the effect of volume in view of potential patient migration. Level of Evidence: Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.1007/s11999-014-3515-z

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Bleeding remains an ongoing concern after total knee arthroplasty (TKA). Intraarticular application of human fibrinogen with a topical thrombin has been described to stop diffuse bleeding in knee arthroplasty. Questions/purposes: It was hypothesized that the use of human fibrinogen as a topical agent would result in a reduction of bleeding and transfusions required after TKA; secondary end points included comparison of early clinical results including pain scores and range of motion (ROM) at 6 weeks and complications after surgery. Methods: Two hundred patients undergoing TKA were randomized into a double-blind clinical trial to receive either intraarticular fibrinogen 2 minutes before tourniquet release or no such treatment. Postoperative hemoglobin and hematocrit levels, drain output, and transfusion requirements were recorded and blood loss was calculated. Clinical outcomes and adverse events were tracked prospectively. Descriptive analysis was performed using a two-sample t-test. Results: There were no differences in calculated blood loss between the fibrinogen and the control groups; the mean postoperative drain output was 780 ± 378 mL in the fibrinogen group compared with 673 ± 301 mL in the control group (p = 0.029), but the hemoglobin drop at Day 2 was 3.47 ± 1.53 g/L in the fibrinogen group and 3.84 ± 1.24 g/Ll in the control group (p = 0.051). There were no differences in in transfusions, early ROM, visual analog pain scores, or complications between the groups. Conclusions: The use of fibrinogen in TKA did not lead to a significant reduction of blood loss or transfusions in primary TKA for osteoarthritis. Given the lack of benefits and the costs this procedure adds to TKA, its routine use cannot be justified during primary TKA for osteoarthritis. Level of Evidence: Level I, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

DOI： 10.1007/s11999-013-3036-1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The multiple-ligament-injured knee represents a special challenge, being an uncommon injury that is both severe and complicated to treat. Many studies have evaluated patients treated for this injury, but most are limited in their scope. The evaluation of this injury and its treatment using an administrative database might provide a different perspective. Questions/purposes: Using a large administrative database, we determined (1) the number of multiligament knee reconstructions in New York State, (2) the rate of 90-day hospital readmission, and (3) the frequency of subsequent knee surgery. We examined the rates of these outcomes as a function of diagnosis, admission type, discharge status, comorbidity burden, and patient demographic factors. Methods: We used the New York Department of Health Statewide Planning and Research Cooperative System (SPARCS), a database with information on patient characteristics, diagnoses, and treatments, to identify patients who underwent a multiligament procedure in a nonfederal facility from 1997 to 2005 using ICD-9-CM and Current Procedural Terminology codes. SPARCS collects data from all nonfederal acute care facilities, with an estimated reporting completeness of almost 99% for the years in this study. We evaluated data on patient age, sex, admission type, discharge status, and comorbidity burden (using Elixhauser comorbidities) and developed a multivariable logistic regression model to assess the influence of confounding variables. Results: We identified 1032 patients in this database who underwent multiligament knee reconstruction in New York State from 1997 to 2005. The frequency of readmission within 90 days was 4.8% (n = 49). Readmission was more likely for patients who underwent inpatient multiligament reconstruction (odds ratio [OR] = 2.3; 95% CI: 1.2-4.4; p = 0.014), had a diagnosis of dislocation (OR = 2.2; 95% CI: 1.2-3.9; p = 0.011), or had various Elixhauser comorbidities, including chronic lung disease (OR = 6.4; 95% CI: 1.5-27.2; p = 0.013), fluid and electrolyte disorders (OR = 19.7; 95% CI: 2.5-155.7; p = 0.005), and anemia deficiency (OR = 5.6; 95% CI: 1.05-29.4; p = 0.044). Two hundred eighty-seven patients (28%) underwent subsequent knee surgery between their index procedure and 2006. Subsequent surgery was more likely for patients who underwent inpatient multiligament reconstruction (OR = 1.4; 95% CI: 1.1-1.9; p = 0.011) or were readmitted within 90 days of the index surgery (OR = 4.2; 95% CI: 2.3-7.6; p < 0.001). Conclusions: Our findings have the potential to aid clinicians in identifying their patients with multiligament reconstruction at highest risk for 90-day readmission and subsequent knee surgery. Future research, particularly large prospective studies evaluating surgical approaches and timing, will be critical in advancing the treatment of multiligament knee injuries. Level of Evidence: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.1007/s11999-014-3653-3

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Venous thromboembolism (VTE) continues to be one of the most important, and highly controversial, topics in orthopaedics. While many surgeons have discussed the incidence and treatment of this potentially life-threatening complication, little has been published about the clinical outcomes of patients who receive treatment and recover from these conditions. We evaluated the clinical outcomes of patients who suffered non-fatal VTE and compared them to a matched cohort with no complications after total knee arthroplasty using our institution's joint arthroplasty registry. At two years, the patient-reported clinical outcomes were equivalent between the groups. While VTE remains an important consideration in total knee arthroplasty, it is helpful for surgeons to know that patient outcomes are not negatively affected after appropriate treatment of these complications.

DOI： 10.1016/j.arth.2013.04.013

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Pulmonary hypertension (PH) is regarded as a risk factor for perioperative complications in patients undergoing noncardiac surgery. Questions/Purposes: The objective of this retrospective case-control study was to evaluate the adverse outcomes of pulmonary hypertension patients undergoing elective unilateral hip replacements. Methods: We performed a retrospective case-control study of total hip replacement patients with pulmonary hypertension (cases) and without pulmonary hypertension (control). From the years 2003 to 2008, we identified a total of 132 patients undergoing primary total hip replacements with a diagnosis of pulmonary hypertension (right ventricular systolic pressure >35). The primary outcome assessed was the incidence of adverse events that occurred during the postoperative hospital stay. Secondary outcomes studied included length of hospital stay, mortality, and ability to reach certain physical therapy milestones. Results: The PH group had significantly more adverse events than the control group. Nonlethal cardiac dysrhythmias comprised the most common adverse outcome among the PH group. Overall, the PH group had a morbidity rate of 34.7% while the control had a rate of 21%. The PH group had longer hospital stay (6.7 days vs. 5.9). Both groups had zero mortality during the hospital stay. The PH group had comparable rehabilitation recovery times than the control group. Conclusion: This retrospective case-control study demonstrates that pulmonary hypertension patients undergoing total hip arthroplasty are more prone to adverse outcomes, especially cardiac dysrhythmias, and longer hospital stays.

DOI： 10.1007/s11420-014-9391-y

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1136/eb-2014-101731

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective:To evaluate population-based systemic lupus erythematosus (SLE) arthroplasty rates and compare them with rates in patients with no inflammatory or autoimmune conditions.Methods: Administrative hospital discharge databases from 10 American states were used to compare knee, hip, and shoulder arthroplasty rates from 1991 to 2005 in patients with SLE and in patients with no inflammatory or autoimmune conditions. Results: Arthroplasties were performed on patients with SLE (n = 4253) and patients with noninflammatory conditions (n = 2,762,660). Arthroplasty rates for patients with noninflammatory conditions almost doubled from 1991 to 2005 (124.5 cases/100,000 persons vs 247.5/100,000; p < 0.001). A similar trend was observed for SLE (0.17/100,000 vs 0.38/100,000; p < 0.001). The mean age at arthroplasty in patients with noninflammatory conditions decreased (71.5 ± 11.8 vs 69.0 ± 12.0; p < 0.001), whereas the mean age in patients with SLE increased (47.3 ± 17.0 vs 56.8 ± 16.0; p < 0.001). When stratified by age and sex, arthroplasty in cases of SLE increased in all groups except for women < 44 years old. In 1991, osteonecrosis accounted for 53% and osteoarthritis (OA) 23% of cases of SLE; by 2005 this relationship had reversed, with osteonecrosis accounting for 24% and OA 61% of cases of SLE. Conclusion: From 1991 to 2005, arthroplasty rates increased in patients with SLE in similar proportions to overall joint replacement rates. The age of patients with SLE arthroplasty increased and fewer cases were due to osteonecrosis. These data suggest significant changes are occurring - patients with SLE are now living long enough to develop OA and are healthy enough to undergo elective surgery.

DOI： 10.3899/jrheum.130617

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Previous research suggests that a substantial percentage of meniscal repairs fail, resulting in a subsequent meniscectomy. Risk factors for failure have been investigated using small cohorts, providing ambiguous results. Purpose: To measure the frequency of and elucidate risk factors for subsequent meniscectomies after meniscal repair using a large study population from multiple surgical centers. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 9529 patients who underwent 9609 outpatient meniscal repairs between 2003 and 2010 were identified from a statewide database of all ambulatory surgery in New York. Patients who subsequently underwent a meniscectomy were then identified. A Cox regression analysis was used to calculate the hazard ratio and 95% confidence intervals. The model included patient age, sex, comorbidities, concomitant arthroscopic procedures, laterality of the meniscus, and surgeon's yearly meniscal repair volume. Results: The overall frequency of subsequent meniscectomies was 8.9%. Patients were at a decreased risk for subsequent meniscectomies if they underwent a concomitant anterior cruciate ligament (ACL) reconstruction (P < .001). Patients undergoing isolated meniscal repairs (without concomitant ACL reconstruction) were at a decreased risk if they were older (P<.001), had a lateral meniscal injury (P = .002), or were operated on by a surgeon with a higher annual meniscal repair volume (>24 cases/year; P<.001). Conclusion: A meniscectomy after meniscal repair is performed infrequently, supporting the notion that repairing a meniscus is a safe and effective procedure in the long term. The risk for undergoing subsequent meniscectomies is decreased in patients undergoing a concomitant ACL reconstruction, in cases of isolated meniscal repairs for patients of older age, and in patients undergoing meniscal repair by surgeons with a high case volume.

DOI： 10.1177/0363546513503444

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Syndesmosis sprains in the National Football League (NFL) can be a persistent source of disability, especially compared with lateral ankle injuries. This study evaluated syndesmosis and lateral ankle sprains in NFL players to allow for better identification and management of these injuries. Syndesmosis and lateral ankle sprains from a single NFL team database were reviewed over a 15-year period, and 32 NFL team physicians completed a questionnaire detailing their management approach. A comparative analysis was performed analyzing several variables, including diagnosis, treatment methods, and time lost from sports participation. Thirty-six syndesmosis and 53 lateral ankle sprains occurred in the cohort of NFL players. The injury mechanism typically resulted from direct impact in the syndesmosis and torsion in the lateral ankle sprain group (P5.034). All players were managed nonoperatively. The mean time lost from participation was 15.4 days in the syndesmosis and 6.5 days in the lateral ankle sprain groups (P≤.001). National Football League team physicians varied treatment for syndesmosis sprains depending on the category of diastasis but recommended nonoperative management for lateral ankle sprains. Syndesmosis sprains in the NFL can be a source of significant disability compared with lateral ankle sprains. Successful return to play with nonoperative management is frequently achieved for syndesmosis and lateral ankle sprains depending on injury severity. With modern treatment algorithms for syndesmosis sprains, more aggressive nonoperative treatment is advocated. Although the current study shows that syndesmosis injuries require longer rehabilitation periods when compared with lateral ankle sprains, the time lost from participation may not be as prolonged as previously reported.

DOI： 10.3928/01477447-20131021-18

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: We investigated the incidence, natural history, and functional consequences of a newly developed flexion contracture after total knee arthroplasty (TKA). Methods: Forty patients with full knee extension preoperatively who developed a postoperative flexion contracture were match-paired 1:2 with 80 patients who had full extension. The incidence of a newly developed flexion contracture, ROM, and Knee Society scores (KSS) at six weeks, four months, and one year were analysed. Results: The incidence of a new flexion contracture at six weeks was 14 %, but diminished to 5 % and 0.3 % at four months and one year, respectively. One year after surgery, there was no difference in the KSS (p = 0.5). Conclusions: This study showed that the majority of patients who developed a new flexion contracture after TKA have full knee extension one year postoperatively. Moreover, knee extension and KSS at one year are equivalent to those patients who did not developed a flexion contracture.

DOI： 10.1007/s00264-013-1993-3

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: We used a statewide database to determine the incidence of pulley reconstruction and to evaluate the influence of demographics on reoperation. We hypothesized that age, insurance status, and concomitant nerve or tendon procedure would influence the likelihood of reoperation. Methods: We used the Statewide Planning and Research Cooperative System ambulatory surgery database from New York, which represents all outpatient surgery in the state. Patients who had flexor pulley reconstruction from 1998 to 2009 were identified using Current Procedural Terminology 4 codes. Subsequent surgery records for these patients were identified through 2010, allowing at least 1 year follow-up. Concomitant nerve procedure and flexor tendon repair/reconstruction were identified. The type and timing of subsequent procedures, including tenolysis and repeat pulley reconstruction, were recorded. Univariate statistics were calculated to compare age, sex, and payer type between patients with and without reoperation. A multivariable, logistic regression model was used to evaluate the association of the demographics with the chances of having reoperation. Results: There were 623 patients who had flexor pulley reconstruction from 1998 to 2009. The incidence of pulley reconstruction was 0.27 per 100,000 persons, with an annual frequency of 52 procedures. There were 39 (6%) reoperations. There was no difference in age, concomitant nerve or tendon repair, or workers' compensation between patients with and without reoperation. Regression modeling showed a higher likelihood among men of having reoperation. Conclusions: Flexor pulley reconstructions are rare. One-quarter of surgeons performed only one flexor pulley reconstruction over a 12-year period. The 6% reoperation rate is similar to our previous findings for flexor tendon repair using similar methodology. Our report provides information that may be useful in counseling patients. Type of study/level of evidence: Prognostic II.

DOI： 10.1016/j.jhsa.2013.05.015

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Obesity affects a disproportionate proportion of total knee arthroplasty (TKA) patients. Our study explores pre-operative characteristics between obese and non-obese patients undergoing TKA surgery. A cohort of 4718 osteoarthritic patients, undergoing primary TKA, was studied. Patients were stratified according to BMI classes. Each class was compared in terms of age, race, gender, level of education, insurance status, pre-operative WOMAC, SF-36, and Elixhauser comorbidities. There was a positive relationship between BMI and female gender, non-white race, Medicaid, private insurance, and self-pay. A negative relationship was observed between BMI and age, Medicare, WOMAC and SF-36. Obese TKA candidates differ from their non-obese counterparts in a number of demographic, socioeconomic, and clinical characteristics.

DOI： 10.1016/j.arth.2012.10.028

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Introduction: The American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Score has been under recent scrutiny. The Foot and Ankle Outcome Score (FAOS) is an alternative subjective survey, assessing outcomes in 5 subscales. It is validated for lateral ankle instability and hallux valgus patients. The aim of our study was to validate the FAOS for assessing outcomes in flexible adult acquired flatfoot deformity (AAFD). Methods: Patients from the authors' institution diagnosed with flexible AAFD from 2006 to 2011 were eligible for the study. In all, 126 patients who completed the FAOS and the Short-Form 12 (SF-12) on the same visit were included in the construct validity component. Correlation was deemed moderate if the Spearman's correlation coefficient was .4 to .7. Content validity was assessed in 63 patients by a questionnaire that asked patients to rate the relevance of each FAOS question, with a score of 2 or greater considered acceptable. Reliability was measured using intraclass correlation coefficients (ICCs) in 41 patients who completed a second FAOS survey. In 49 patients, preoperative and postoperative FAOS scores were compared to determine responsiveness. Results: All of the FAOS subscales demonstrated moderate correlation with 2 physical health related SF-12 domains. Mental health related domains showed poor correlation. Content validity was high for the Quality of Life (QoL; mean 2.26) and Sports/Recreation subscales (mean 2.12). All subscales exhibited very good test-retest reliability, with ICCs of .7 and above. Symptoms, QoL, pain, and daily activities (ADLs) were responsive to change in postoperative patients (P < .05). Conclusion: This study has validated the FAOS for AAFD with acceptable construct and content validity, reliability, and responsiveness. Given its previous validation for patients with ankle instability and hallux valgus, the additional findings in this study support its use as an alternative to less reliable outcome surveys. Level of Evidence: Level II, prospective comparative study.

DOI： 10.1177/1071100713483117

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Radiographic assessment of skeletal age in pediatric patients is a common practice among orthopaedic surgeons. Current methods of assessment remain labor intensive and require special resources. This study sought to investigate a novel, abridged method of bone age assessment that may serve as a simpler and more efficient alternative to the current standard. METHODS: A shorthand bone age (SBA) method developed at our institution was compared against the Greulich and Pyle method from which it was derived. Standard left hand bone age radiographs of 140 male and 120 female patients, previously assigned skeletal ages ranging from 12.5 to 16 years in males and 10 to 16 years in females by musculoskeletal radiologists using the Greulich and Pyle radiographic atlas, were read using the shorthand method by 3 attending pediatric orthopaedic surgeons and an orthopaedic surgery resident. The shorthand method utilizes a single, univariable criterion for each age, rather than a multivariable subjective comparison to a radiographic atlas. All reviewers were blinded to the original bone age determination. Interobserver reliability, intraobserver reliability, and agreement with the previous records utilizing the atlas were calculated using weighted κ. RESULTS: The SBA method readings demonstrated substantial agreement with readings by the Greulich and Pyle atlas, demonstrating weighted κ values ranging from 0.71 to 0.75. The SBA method also demonstrated substantial to almost perfect interobserver and intraobserver reliability, with values ranging from 0.77 to 0.87 and from 0.87 to 0.95, respectively. CONCLUSIONS: These results are comparable or superior to previous reports which investigate the validity and reliability of other skeletal age assessment tools. The SBA assessment tool offers a simple and efficient alternative to current methods. LEVEL OF EVIDENCE: Diagnostic study, level III.

DOI： 10.1097/BPO.0b013e318293e5f2

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The use of interscalene blocks (ISBs) for shoulder surgery improves postoperative pain control, reduces recovery room times, and reduces overall hospital stays. The most common and potentially disabling adverse effect associated with ISBs is phrenic nerve paresis. Fortunately, persistent phrenic nerve paresis (PPNP) is rare. There are only 4 case reports of PPNP in the English literature. At our institution, we identified 9 cases of PPNP over a 9-year period, representing an incidence of 1 (0.048%) in 2069. In conducting a case-control series, we found that symptomatic cervical spine disease is a risk factor for the development of PPNP. Patients with PPNP had a significantly higher incidence of cervical spine disease (85.7%) compared with the control group (30.9%), P < 0.01. Persistent phrenic nerve paresis remains a perplexing complication of ISB, and many questions remain unanswered. Our data identify an important risk factor that can aid in the risk stratification of patients undergoing ISB.

DOI： 10.1097/AAP.0b013e318289e922

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objectives. Two prior studies suggested that coeliac disease (CD) has a higher prevalence rate (8%) in SSc than in the general population (1%), but these studies were limited by small numbers and the use of traditional coeliac screening antibody tests, where newer ones with improved accuracy have since emerged. Our aim was to determine the prevalence of CD in a larger SSc population using a more modern serological approach to coeliac testing and to correlate coeliac antibody status with gastrointestinal symptoms.Methods. Stored sera from 72 SSc patients in the Scleroderma Registry at the Hospital for Special Surgery were tested for anti-tissue transglutaminase (traditional) and anti-deamidated gliadin peptide (novel) antibodies. If any of these antibodies were positive, anti-endomysial antibodies were tested and confirmatory small-bowel endoscopy and biopsy were obtained. Registry clinical data were used to determine whether antibody status correlated with gastrointestinal symptoms.Results. The prevalence of coeliac antibodies in our SSc population was 3/72 (4%). No significant differences with respect to gastrointestinal symptoms were seen in the coeliac antibody-positive compared with -negative SSc patients. No cases of confirmed CD were seen in our cohort.Conclusion. Contrary to the only two previously published studies, the low prevalence of CD that we found does not suggest that concurrent CD is a common cause of gastrointestinal complaints in SSc patients.

DOI： 10.1093/rheumatology/kes390

記述言語：英語   掲載種別：研究論文（学術雑誌）  

While obesity is associated with increased need for total hip arthroplasty (THA), the relationship between body mass index (BMI) and operative duration is unknown. We reviewed a series of 425 primary THAs implanted by one surgeon from 2004 to 2010. Patients were grouped by BMI based on the World Health Organization's categorization. Intraoperative time measurements (Total Room Time, Anesthesia Induction Time, Surgery Time) were compared across groups. Mean times were analyzed using a one-way ANOVA with post-hoc least squares difference test. Operating time increased progressively with increasing BMI category. Significant differences were found between normal weight patients and all 3 obesity groups in total room and surgery times. Obese patients spend more time in the OR during THA, reflecting the burden obesity poses to surgeons and hospitals.

DOI： 10.1016/j.arth.2012.06.037

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Study design: Retrospective cohort study. Objective: To evaluate falls among elective orthopaedic inpatients at a musculoskeletal hospital. Background: Falls are the most commonly reported hospital incidents. Approximately 30% of in-hospital falls result in minor injury, and up to 8% of falls result in moderate to severe injury. Given the projected rise in elective orthopaedic procedures, it is important to better understand fall patterns in this population. Methods: A retrospective review of electronic medical records and patient charts (2000-2009) was conducted to identify falls in patients admitted for elective orthopaedic procedures. Results: There were 868 falls among orthopaedic patients older than 18 years. The fall rate was 0.9% of admissions, or 2.0 falls per 1000 inpatient days. The average age of the patients who had fallen was 68 years, and 57.6% were women. Knee replacements (38.2%), spine procedures (18.5%), and hip replacements (14.7%) were the procedures most commonly associated with falls. Three hundred eighty-six falls (45.8%) involved bathroom usage. One hundred ten first falls (13.1%) resulted in injuries. Twenty-eight falls (3.3%) resulted in serious events, including 5 returns to the operating room, 3 transfers to a higher level of care, 14 prosthesis dislocations, 6 fractures, 2 intracranial bleeds, and 1 hemorrhage. Patients with serious injuries were more likely to fall earlier (mean postoperative days, 2.7 versus 4.1; mean difference, 1.4 days; 95% confidence interval: 0.51, 2.3; P = .003) and to have had hip replacement (odds ratio = 3.7; 95% confidence interval: 1.7, 8.2). Serious injuries were not associated with body mass index, age, gender, hospital location, day, or fall history. Conclusion: Falls are avoidable events that are poorly described among orthopaedic patients having elective procedures. This large series identifies hip replacement patients as being at almost 4-fold risk of having a serious adverse event after falling. Larger prospective trials are needed to confirm results and to inform prevention strategies.

DOI： 10.2519/jospt.2013.4349

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: To determine the incidence of elbow contracture requiring release after surgically treated elbow trauma and to identify patient, injury, and treatment factors that may predict contracture development. Methods: The New York Statewide Planning and Research Cooperative System database identified 32,708 patients who were surgically treated for elbow trauma from 1997 to 2009. The database identified 270 of those patients who underwent subsequent contracture release. The median time from index fracture procedure to contracture release was 31 weeks. Results: Patients requiring a contracture release were younger (43 vs 56 y) and more commonly male (57%). Injuries classified as severe were more common in the contracture group (11% vs 5%), as were open fractures (17% vs 11%). A multivariate regression analysis revealed that patients with burns were 16 times more likely to require surgical contracture release, and the use of internal fixation to treat the fracture was protective against contracture development. Conclusions: The incidence of elbow contractures treated with release after surgically treated elbow trauma was low but increased with the severity of the initial trauma. Level of evidence: Prognostic II.

DOI： 10.1016/j.jhsa.2013.05.005

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Patients with poor health literacy often lack the knowledge needed to manage their treatment. Objective: The aim of this cross-sectional study is to determine whether health literacy is a predictor of health knowledge and/or adherence to medication treatment in patients with rheumatoid arthritis. Method: The study was completed in an urban, outpatient rheumatology setting. Health literacy was measured using the Test of Functional Health Literacy in Adults. The Arthritis Knowledge Questionnaire was modified to measure medication specific health knowledge, and the Morisky Medication Adherence scale was used to measure adherence. Researchers used regression analyses to determine if health literacy was a predicator of knowledge and/or adherence. Results: Participants (N = 125) had high mean health literacy scores. The average medication knowledge score was 0. 73. Adherence to medication regimen was 0. 84. Controlling for patient covariates, health literacy was positively associated with education, race, and age. In adjusted analyses, health literacy was a significant predictor of health knowledge but not adherence. Race, neighborhood income, and confidence with contacting provider about medications were predictors of adherence. Conclusion: Study findings indicate that health literacy is independently associated with medication knowledge but not medication adherence in patients with rheumatoid arthritis. These results provide useful information for planning initiatives to support individuals with disease self-management.

DOI： 10.1007/s11420-012-9308-6

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: To compare hip morphology between young men and women who presented with hip pain and labral tears. Methods: A retrospective review of our hip arthroscopy registry from March 2008 to June 2010 was completed. We identified 217 patients (249 hips) who were between the ages of 18 to 30 years. The inclusion criteria were (1) insidious-onset hip pain or worsening pain after low-energy sports trauma, (2) positive hip impingement sign, (3) Tönnis grades 0 to 1, (4) magnetic resonance imaging showing labral tear, and (5) primary hip arthroscopy confirming labral tear. Forty-five patients (52 hips) were excluded for the following reasons: (1) revision hip arthroscopy, (2) high-energy hip trauma, (3) history of surgery involving the femur or pelvis, (4) previous fractures of the femur or pelvis, (5) Tönnis grades 2 or above, (6) proliferative disease of the hip (i.e., synovial chondromatosis, pigmented villonodular synovitis), (7) neuromuscular disease (i.e., cerebral palsy), and (8) deformities related to Legg-Calvé-Perthes disease or developmental dysplasia of the hip. Therefore, the cohort study group included 105 (61%) men (123 [62.4%] hips) and 67 (39%) women (74 [37.6%] hips). Sex comparisons were made for the following variables measured on preoperative hip computed tomography scans: alpha angle, acetabular version, femoral version, lateral center-edge angle, and neck-shaft angle. Results: Women had smaller alpha angles (47.8° v 63.6°, P <.001), increased acetabular version (17.3° v 13.9°, P <.001), and increased femoral anteversion (14.4° v 12.1°, P =.05). Conclusions: In young adults with hip pain and labral tears, women have smaller alpha angles and hips that are generally more anteverted. Therefore, in women, cam lesions may be more subtle, preoperative hip version analyses should be encouraged, and rim trimming may need to be cautiously planned to avoid increasing contact stresses at weight-bearing areas after such a procedure. Level of Evidence: Level III, retrospective comparative study.

DOI： 10.1016/j.arthro.2012.07.008

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The aim of this study was to quantify the effects of distal femoral cut height on maximal knee extension and coronal plane knee laxity. Methods: Seven fresh-frozen cadaver legs from hip-to-toe underwent a posterior stabilized TKA using a measured resection technique with a computer navigation system equipped with a robotic cutting guide. After the initial femoral resections were performed, the posterior joint capsule was sutured until a 10° flexion contracture was obtained with the trial components in place. Two distal femoral recuts of +. 2. mm each were then subsequently made and the trials were reinserted. The navigation system was used to measure the maximum extension angle achieved and overall coronal plane laxity [in degrees] at maximum extension, 30°, 60° and 90° of flexion, when applying a standardized varus/valgus load of 9.8 [Nm] across the knee. Results: For a 10. degree flexion contracture, performing the first distal recut of +. 2. mm increased overall coronal plane laxity by approximately 4.0° at 30° of flexion (p = 0.002) and 1.9° at 60° of flexion (p = 0.126). Performing the second +. 2. mm recut of the distal femur increased mid-flexion laxity by 6.4° (p. <. 0.0001) at 30° and 4.0° at 60° of flexion (p = 0.01), compared to the 9. mm baseline resection (control). Maximum knee extension increased from 10° of flexion to 6.4° (±. 2.5°. SD, p. <. 0.005) and to 1.4° (±. 1.8° SD, p. <. 0.001) of flexion with each 2. mm recut of the distal femur. Conclusions: Recutting the distal femur not only increases the maximum knee extension achieved but also increases coronal plane laxity in midflexion.

DOI： 10.1016/j.knee.2012.05.007

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Patient-reported outcome questionnaires such as the Foot and Ankle Outcome Score (FAOS) are useful in evaluating results after orthopedic interventions. However, despite being frequently used in the literature, its validity has not been established for forefoot disorders. Our study aimed to validate the FAOS for use in assessing outcomes of hallux valgus surgery. Methods: From 2006 to 2009, 195 patients with nonarthritic hallux valgus were included in the construct validity portion of the study. Patients had a SF-36 and a FAOS completed. Forty additional patients, both preoperative and postoperative, were given questionnaires to assess the relevance of each of the FAOS questions as it pertained to their bunions. Patients were also given the FAOS 1 month after the first to assess FAOS reliability. Responsiveness of the FAOS was included with 40 patients who had both preoperative and postoperative FAOS scores. Results: Four out of five FAOS subscales demonstrated acceptable correlation with the SF-36. The FAOS symptoms subscale showed the least correlation with SF-36, demonstrating the foot-specific nature of the questions. Both preoperative and postoperative patients rated the FAOS quality of life questions as the most relevant. All five subscales achieved acceptable test-retest reliability. The FAOS sports and recreation subscale was the least responsive. Conclusion: Patient-based assessments have become increasingly important in evaluating treatment effectiveness. This study has shown that the FAOS has acceptable construct validity, reliability, and responsiveness in hallux valgus patients and is a useful patient-based tool in assessing these patients.

DOI： 10.3113/FAI.2012.1145

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Component malalignment can be associated with pain following total knee replacement (TKR). Using MRI, we reviewed 50 patients with painful TKRs and compared them with a group of 16 asymptomatic controls to determine the feasibility of using MRI in evaluating the rotational alignment of the components. Using the additional soft-tissue detail provided by this modality, we also evaluated the extent of synovitis within these two groups. Angular measurements were based on the femoral transepicondylar axis and tibial tubercle. Between two observers, there was very high interobserver agreement in the measurements of all values. Patients with painful TKRs demonstrated statistically significant relative internal rotation of the femoral component (p = 0.030). There was relative internal rotation of the tibial to femoral component and combined excessive internal rotation of the components in symptomatic knees, although these results were significant only with one of the observers (p = 0.031). There was a statistically significant association between the presence and severity of synovitis and painful TKR (p < 0.001). MRI is an effective modality in evaluating component rotational alignment.

DOI： 10.1302/0301-620X.94B9.28489

記述言語：英語   掲載種別：研究論文（学術雑誌）  

This study evaluated concordance between self-reports and surgeon assessments of short-term complications. A total of 3976 primary total hip arthroplasty patients consented for an institutional registry (5/2007-12/2008); 3186 (80.1%) completed a 6-month survey; 137 (4.4%) reported deep venous thrombosis, pulmonary embolism, major bleeding, fracture, or dislocation. Patients reporting complications were called. Positive predictive values and 95% confidence intervals (95% CI) for patient self-report were measured, using surgeon assessment for comparison: pulmonary embolism, 88.9% (95% CI, 78.4%-99.4%); dislocation, 81.1% (95% CI, 75.9%-86.5%); fracture, 73.7% (95% CI, 63.8%-83.5%); deep venous thrombosis, 69.7% (95% CI, 61.9%-77.5%); major bleeding, 32.0% (95% CI, 19.4%-44.5%); any bleeding, 88.0% (95% CI, 75.3%-99.9%). Of 97 confirmed complications, 64.95% presented to outside institutions. Registry data on self-reported complications may overcome limitations of traditional methods, but data should be interpreted cautiously. Concordance was high for PE and dislocation but low for major bleeding.

DOI： 10.1016/j.arth.2011.10.031

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Introduction: Blood loss following total knee arthroplasty can lead to substantial morbidity and the need for blood transfusions. Hemostatic agents have been used to minimize blood loss and to decrease transfusion rates. Floseal is a thrombinbased hemostatic agent with unknown efficacy for achieving these goals in patients undergoing total knee arthroplasty. Methods: We performed a prospective randomized controlled trial on the use of Floseal in patients undergoing total knee arthroplasty, with the primary end point being blood loss as measured through drain output. Demographic characteristics, operative side, diagnosis, intraoperative details, implant choice, hospital course, laboratory values, visual analog scale pain scores, knee range of motion, adverse events, transfusion rates, and deviations from protocol were recorded. Results: A total of 196 patients were enrolled, with ninety-seven patients being randomized to the Floseal group and ninety-nine patients being randomized to the control group. There were no significant differences between the Floseal and control groups in terms of drain output at twenty-four hours (711 compared with 702 mL; p = 0.823). No differences were noted between the groups in terms of operative side, diagnosis, intraoperative details, implant choice, hospital course, laboratory values, visual analog scale pain scores, knee range of motion, or transfusion rates. Complications occurred infrequently. In the acute postoperative period, there were two cases of cellulitis (one in each group), two deep venous thromboses (one in each group), and one paralytic ileus (in the control group), all of which resolved with nonoperative measures. At the six-week follow-up, one patient in the Floseal group had died from a cause unrelated to surgery, two patients (one in each group) had suture abscesses with cellulitis that resolved with postoperative antibiotics, and four patients (two in each group) underwent knee manipulation under anesthesia to achieve improved knee motion. With the numbers available, there was no significant association between Floseal use and the occurrence of these adverse events. Conclusions: The present study showed that Floseal had no demonstrable effect on blood loss as measured through drain output following total knee arthroplasty. There were also no notable adverse events associated with its use. The usefulness of Floseal as a hemostatic agent in total knee arthroplasty remains unclear. Level of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.K.00531

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Obesity is associated with increased complications related to total knee arthroplasty (TKA), but the relationship between body mass index (BMI) and operating room time during TKA is unknown. A total of 454 unilateral primary TKAs (2005-2009) were reviewed and categorized by BMI (normal weight, 18.5-25 kg/m²; overweight, 25-30 kg/m²; obese class I, 30-<35 kg/m²; class II, 35-40 kg/m²; class III, >40 kg/m²). Intraoperative time measurements (total room time, anesthesia induction time, tourniquet time, closing time, surgery time) were compared across the BMI groups. Comparing normal weight to obese class III, time differences were significant in total room time (24 minutes, P < .01), surgery time (16 minutes, P < .01), tourniquet time (7.5 minutes, P < .01), and closure time (8 minutes, P < .01). Armed with this information, BMI can be used to better allocate operating room time for TKA.

DOI： 10.1016/j.arth.2011.12.012

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: To describe the incidence of reoperation and the demographic factors that may be associated with reoperation after flexor tendon repair. Methods: Using a New York statewide hospital administrative database covering an 8-year period, we examined unique patient discharges with an index procedure of flexor tendon repair for reoperation (re-repair or tenolysis). We compared the age, sex, race, and insurance type by reoperation status using standard univariate statistics and multivariate regression analysis. We performed trend analysis using the Cochran-Armitage trend test. Results: From 1998 to 2005, there were 5,229 flexor tendon repairs with a frequency of reoperation of 6%; of these, 91% were in the first year after the primary procedure. Those who underwent reoperation were significantly older than those who did not undergo reoperation. Patients with workers' compensation were 63% more likely to undergo reoperation than those with other forms of insurance. Patients who had concomitant nerve repair during the index procedure were 26% less likely to undergo reoperation. The rate of reoperation did not change during the study period. Conclusions: These results may be useful in shaping research agendas to evaluate sociodemographic factors contributing to reoperations. Type of study/level of evidence: Prognostic II.

DOI： 10.1016/j.jhsa.2012.02.003

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Anterior cruciate ligament (ACL) tears have been implicated in the development of osteoarthritis. Limited data exist on longitudinal follow-up of isolated ACL injury.Hypotheses: All isolated ACL tears are associated with some degree of cartilage injury that will deteriorate over time. There is a threshold of magnetic resonance imaging (MRI)-detectable cartilage injury that will correlate with adverse change in subjective patient-reported outcome measures.Study Design: Cohort study, Level of evidence, 2.Methods: The authors conducted a prospective, observational analysis of 42 knees in 40 patients with acute, isolated ACL injury (14 treated nonoperatively, 28 by reconstruction) with imaging at the time of injury and yearly follow-up for a maximum of 11 years. Morphologic MRI and quantitative T2 mapping was performed with validated outcome measures.Results: All patients sustained chondral damage at initial injury. The adjusted risk of cartilage loss doubled from year 1 for the lateral compartment and medial femoral condyle (MFC) and tripled for the patella. By years 7 to 11, the risk for the lateral femoral condyle was 50 times baseline, 30 times for the patella, and 19 times for the MFC. There was increased risk of cartilage degeneration over the medial tibial plateau (MTP) (P =.047; odds ratio = 6.23; 95% confidence interval [CI], 1.03-37.90) and patella (P =.032; odds ratio = 4.88; 95% CI, 1.14-20.80) in nonsurgical patients compared with surgically treated patients. Size of the bone-marrow edema pattern was associated with cartilage degeneration from baseline to year 3 (P =.001 to.039). Each increase in the MFC Outerbridge score resulted in a 13-point decrease in the International Knee Documentation Committee subjective knee score (P =.0002). Each increase in the MTP resulted in a 2.4-point decrease in the activity rating scale (P =.002).Conclusion: All patients with acute, traumatic ACL disruption sustained a chondral injury at the time of initial impact with subsequent longitudinal chondral degradation in compartments unaffected by the initial "bone bruise," a process that is accelerated at 5 to 7 years' follow-up.

DOI： 10.1177/0363546511423380

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The objective of this study was to compare preoperative expectation scores between stages in patients with bilateral total knee arthroplasty (TKA) and total hip arthroplasty (THA) using intraclass correlation coefficients (ICCs). For patients with TKA (57), ICC was 0.449, indicating fair agreement between stages; expectations did not change for 31% of patients, whereas 40% had higher and 29% had lower expectations. For patients with THA (55), ICC was 0.663, indicating moderate agreement; expectations did not change for 42% of patients, whereas 38% had higher and 20% had lower expectations. In multivariable analyses controlling for first expectation score, second expectation score was associated with better Western Ontario McMaster Universities Osteoarthritis Index stiffness score for TKA and with worse Western Ontario McMaster Universities Osteoarthritis Index function score for patients with THA. For most patients, expectations changed between staged bilateral TKA and THA, but the direction of change was not uniform.

DOI： 10.1016/j.arth.2012.02.004

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: To identify clinical variables that affect a surgeon's decision to recommend arthroscopic partial meniscectomy (APM). Methods: Members of 2 orthopaedic specialty societies were invited to participate in an online survey by e-mail. The survey consisted of surgeon demographics and case scenarios to evaluate clinical decision making for APM. Posterior probabilities were calculated to determine the effect of clinical factors on the likelihood of recommending APM. Results: Of the respondents with valid e-mail addresses, 733 (19.3%) returned a completed survey, but only 533 (14.1%) met the eligibility criteria (treated or referred an APM candidate within the past year). Respondents were aged 46.7 ± 9.4 and had performed a mean of 115 APMs in the previous year. Posterior probabilities for a combination of 6 clinical indicators identified 3 factors that most influenced a surgeon's decision to recommend APM: radiographic findings, McMurray test, and failure of nonoperative management. Conclusions: Significant variation exists among practicing orthopaedic surgeons with regard to decision making for APM. The 3 clinical factors that most influenced a surgeon's decision to recommend APM were normal radiographic findings, failed nonoperative treatment, and the presence of positive physical examination findings (i.e., positive McMurray test, joint line tenderness, and effusion). Level of Evidence: Level III, decision analysis.

DOI： 10.1016/j.arthro.2011.09.004

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Total elbow arthroplasty was originally used to treat patients with arthritis. As familiarity with total elbow arthroplasty evolved, the indications were expanded to include other disorders. There continues to be a low number of total elbow arthroplasties performed each year in comparison with hip, knee, and shoulder arthroplasties, and few large studies have examined the indications and associated complications of total elbow arthroplasty. The purposes of this study were to evaluate the changes with time in the indications for total elbow arthroplasty and to examine the complications of this procedure in a large database. Methods: The Statewide Planning and Research Cooperative System database from the New York State Department of Health, a census of all ambulatory and inpatient surgical procedures in the state of New York, was used to identify individuals who underwent primary total elbow arthroplasty during the time period of 1997 to 2006. These total elbow arthroplasties were evaluated for admitting diagnoses, sex and age of patient, readmission and complication data, and time to subsequent elbow surgery. Results: From 1997 to 2006, there were 1155 total elbow arthroplasties performed in New York State. In 1997, 43% of the total elbow arthroplasties were associated with trauma and 48%, with inflammatory conditions. In 2006, this changed to 69% and 19%, respectively. Within ninety days after the primary total elbow arthroplasty, 12% of the patients were readmitted to the hospital with approximately one-half (5.6%) admitted for problems related to the total elbow arthroplasty. The overall revision rate was 6.4%. The revision rates for the traumatic, inflammatory arthritis, and osteoarthritis groups were 4.8%, 8.3%, and 14.7%, respectively. Of particular interest, 90.5% of the total elbow arthroplasties were performed by surgeons with no recorded experience in the database, which began collecting these data in 1986. Conclusions: This study provides useful information regarding patients undergoing total elbow arthroplasty in New York State. During the study period, the most common indication for total elbow arthroplasty changed from inflammatory arthritis to trauma. Although the number of total elbow arthroplasties being performed each year has increased, there continues to be a high complication and revision rate. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.J.01128

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Ankle arthrodesis may be achieved using the Ilizarov method. Comorbidities, such as diabetes, Charcot neuroarthropathy, osteomyelitis, leg length discrepancy, and smoking, can make an ankle fusion complex and may be associated with lower rates of healing. Questions/Purposes: We asked if (1) smoking and other comorbidities led to lower fusion rates, (2) time wearing the frame affected outcome, and (3) simultaneous tibial lengthening improved fusion rates. Methods: We retrospectively studied 101 patients who underwent complex ankle fusion using the Ilizarov technique. The median time wearing the frame was 25 weeks (range, 10-65 weeks). Twenty-four patients had simultaneous tibial lengthening. The minimum followup for 91 of the 101 patients was 27 months (median, 65 months; range, 27-134 months). Results: Fusion was achieved in 76 of 91 patients. Smoking was associated with a 54% rate of nonunion. Fifteen of 19 patients with Charcot neuroarthropathy achieved union but had a high rate of subsequent subtalar joint failure. Time wearing the frame did not affect union rates. Tibial lengthening did not improve ankle fusion rates. Conclusion: Smokers should be warned of the high risk of nonunion and we recommend they quit smoking. We also recommend surgeons recognize the higher nonunion rate in patients with Charcot neuroarthropathy. We believe tibial lengthening should not be performed to enhance healing at the fusion site. Level of Evidence: Level IV, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

DOI： 10.1007/s11999-012-2470-9

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Current trends in total joint replacement have focused on shorter hospital stays. Purpose: This study aimed to determine if a pathway for total hip replacement (THR) with the goal of a 2-day discharge (fast track) is safe and effective compared to our traditional pathway (control). Methods: One hundred forty-nine patients undergoing unilateral, uncomplicated, THR were enrolled in an accelerated postoperative pathway and 134 were enrolled in the traditional pathway. Patients were followed prospectively and outcomes included hospital length of stay, intra- and postoperative complications, readmissions, reoperations. A statistical model was created to determine factors predictive of a 2-day discharge. Results: At 1 year, there were no differences in complications, readmissions, or reoperations. The average length of stay decreased from 4.1 to 2.6 days (p & 0.0001). In the fast track group, 58% of patients were discharged home within 2 days. Barriers to a 2-day discharge were postoperative pain, nausea, and dizziness. The only preoperative factor that was predictive of a 2-day discharge was hypertension. Conclusions: In a select group of patients, a protocol that allows for a 2-day discharge following THR is safe and effective.

DOI： 10.1007/s11420-011-9207-2

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: Lower extremity alignment is an important consideration prior to cartilage surgery and/or osteotomy about the knee. This is measured on full length standing hip to ankle radiographs, which has traditionally been done using hard copy radiographs. However, the advent of PACS (Picture Archiving and Communication Systems) has allowed these measurements to be done on computer based digital radiographs. The objectives of this study were to evaluate the intra- and inter-observer reliability of lower limb alignment measures manually obtained from hard copy radiographs versus using the Philips Easy Vision system, and to assess the subjective ease of use for the two methods. Methods: Forty-two patients who underwent surgery and who had a standing hip to ankle radiograph on file were identified. Four raters, including two radiologists and two orthopaedic surgeons, measured each hard copy radiograph and computer image on two separate occasions. Three measurements were recorded for each hard copy radiograph and computer image-width of tibial plateau, the distance from the medial aspect of the tibial plateau to the weight-bearing line, and the mechanical axis. Results: All correlations for this study were high. For tibial plateau data, the hard copy radiographs compared to PACS demonstrated intra-class correlation coefficients (ICC) ranging from 0.93 to 0.99 for inter-rater reliability for the four raters. The ICC for intra-rater reliability for hard copies ranged from 0.90 to 0.99 and for PACS from 0.94 to 0.99. The inter-rater data comparing raters ranged from 0.87 to 0.98 for hard copy radiographs and from 0.98 to 0.99 for PACS. For mechanical axis data, the ICC for hard copy radiograph compared to PACS ranged from 0.93 to 0.97 for the intra-rater reliability for the four raters. The intra-rater reliability for mechanical axis data on hard copy radiograph ranged from an ICC of 0.86 to 0.96, and for PACS the ICC ranged from 0.93 to 0.99. The inter-observer data for hard copy radiographs using the mechanical axis ranged from 0.88 to 0.94 and for PACS ranged from 0.93 to 0.97. The physicians rated PACS as statistically significantly easier to use when compared to hard copy (P = 0.03). Conclusion: Evaluation of lower extremity alignment using two techniques prior to knee surgery was found to have higher inter- and intra-observer reliability using PACS software. PACS is now used prior to cartilage surgery and/or osteotomy to measure both alignment and the location of the weight bearing line on the tibial plateau both before and after surgery. Level of evidence: Diagnostic study, Level I.

DOI： 10.1007/s00167-011-1467-3

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Context: Implantable cardioverter-defibrillators (ICDs) have diffused rapidly into clinical practice with little evaluation of their real-world effectiveness. Objectives: To determine the effect of the adoption of ICD on patient safety, particularly with respect to physician volume and early outcomes. Design: Retrospective cohort of all ICD implantations in New York state from 1997 to 2006, with follow-up at 90 days and 1 year. Setting: New York state non-federal hospital discharges in which an ICD was implanted during the admission. Patients were followed forward for 1 year for subsequent admissions. Patients: New York state residents undergoing ICD implantation. Main outcome measures: Effects of annual and career ICD implantation volume on 90-day complication, readmission, reprogramming, mortality and revision of the ICD within 1 year. Results: This cohort (N=38 992) represents a period of rapid adoption and implementation of this new technology, with frequency more than tripling between 1997 and 2006. We identified 6439 (16.5%) postimplantation complications and 1093 (2.8%) deaths within 90 days of implantation. The majority (73.4%) of physicians implanted one or fewer ICDs per year, and 11.0% of all implantations were performed by these very-low-volume operators. Patients treated by very-lowvolume operators were more likely to die (RR=1.8, 95% CI 1.3 to 2.4) or experience cardiac complications (RR=4.7, 95% CI 3.3 to 6.8) even after the adjustment for case mix compared to operators who frequently performed ICD implantation. Conclusions: These findings suggest a need for safe and effective implementation strategies for new medical technologies, which minimize patient risk due to rapid diffusion among inexperienced providers and assure that the intended benefit can be maximised rapidly.

DOI： 10.1136/hrt.2011.226282

記述言語：英語   掲載種別：研究論文（学術雑誌）  

We evaluated the average 7-year survivorship and clinical results of a newer primary posterior stabilized total knee arthroplasty (TKA). The modifications in this design included a deeper patellar sulcus aimed at reducing contact stresses, improving patellar tracking, and achieving greater maximum flexion. A consecutive group of 137 patients (171 knees) who underwent TKAs using the Optetrak PS knee prosthesis between October 1997 and March 2004 were followed for an average of 6.8 years (range 4.0-11.5 years). Preoperative range of motion (ROM) and Knee Society scores were obtained and compared to that of the patients' most recent follow-up. Manipulation under anesthesia (MUA) and revision of the implant for any reason were considered endpoints for Kaplan-Meier survival analysis of all knees. Twenty-one knees (12.3%) underwent MUA. Three knees (1.8%) underwent revision, resulting in a 97.2% survival at a mean 10 years follow-up. Pain scores and ROM significantly improved after surgery (from preoperative average of 5.3 and 105° respectively to 44.6 and 120° postoperatively). These findings suggest that this posterior stabilized knee design is both a safe and effective option for patients undergoing primary TKA.

DOI： 10.1007/s11420-011-9196-1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective To assess the safety and effectiveness of imatinib mesylate in the treatment of diffuse cutaneous systemic sclerosis (dcSSc). Methods In this phase IIa, open-label, single-arm clinical trial, 30 patients with dcSSc were treated with imatinib 400 mg daily. Patients were monitored monthly for safety assessments. Modified Rodnan skin scores (MRSS) were assessed every 3 months. Pulmonary function testing, chest radiography, echocardiography and skin biopsies were performed at baseline and after 12 months of treatment. Results Twenty-four patients completed 12 months of therapy. 171 adverse events (AE) with possible relation to imatinib were identified; 97.6% were grade 1 or 2. Twenty-four serious AE were identified, two of which were attributed to study medication. MRSS decreased by 6.6 points or 22.4% at 12 months (p=0.001). This change was evident starting at the 6-month time point (δ=-4.5; p<0.001) and was seen in patients with both early and late-stage disease. Forced vital capacity (FVC) improved by 6.4% predicted (p=0.008), and the diffusion capacity remained stable. The improvement in FVC was significantly greater in patients without interstitial lung disease. Health-related quality of life measures improved or remained stable. Blinded dermatopathological analysis confirmed a significant decrease in skin thickness and improvement in skin morphology. Conclusions Treatment with imatinib was tolerated by most patients in this cohort. Although AE were common, most were mild to moderate. In this open-label experience, improvements in skin thickening and FVC were observed. Further investigation of tyrosine kinase inhibition for dcSSc in a double-blind randomised placebo controlled trial is warranted. ClinicalTrials.gov, NCT00555581.

DOI： 10.1136/ard.2010.143974

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Shoulder instability and surgical stabilization are common in college football athletes. The effect of shoulder stabilization during college on the length of an athlete's career in the National Football League (NFL) has not been well examined. Hypothesis: Athletes with a history of shoulder stabilization before the NFL combine have a shorter career than do matched controls. Study Design: Cohort study; Level of evidence, 3. Methods: A database containing the injury history and career NFL statistics of athletes from 1987 to 2000 was used to match athletes with a history of shoulder stabilization and no other surgery or significant injury to controls without a history of any previous surgery or significant injury. Athletes were matched by position, year drafted, round drafted, and additional minor injury history. Results: Forty-two athletes with a history of shoulder stabilization were identified and matched with controls. A history of shoulder stabilization significantly reduced the length of career in terms of years (5.2 ± 3.9 vs 6.9 ± 3.6 years; P =.01) and games played (56 ± 53 vs 77 ± 50, P =.03) as compared with controls. By position, linemen and linebackers (20 athletes) with a history of shoulder stabilization had a significantly shorter career in years (4.7 ± 3.8 vs 6.7 ± 3.4 years; P =.049) and games played (51 ± 58 vs 81 ± 48; P =.046) than did controls. Among the other positions (22 athletes), the difference was not statistically significant in this small cohort. Conclusion: A history of shoulder stabilization shortens the expected career of a professional football player, particularly for linemen and linebackers. Further research is warranted to better understand how these injuries and surgeries affect an athlete's career and what can be done to improve the long-term outcome after treatment.

DOI： 10.1177/0363546510382887

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The risk of elbow or shoulder injury for young baseball pitchers is unknown. Purpose/Hypothesis: The purpose of this study was to quantify the cumulative incidence of throwing injuries in young baseball pitchers who were followed for 10 years. Three hypotheses were tested: Increased amount of pitching, throwing curveballs at a young age, and concomitantly playing catcher increase a young pitcher's risk of injury. Study Design: Cohort study; Level of evidence, 3. Methods: In sum, 481 youth pitchers (aged 9 to 14 years) were enrolled in a 10-year follow-up study. Participants were interviewed annually. Injury was defined as elbow surgery, shoulder surgery, or retirement due to throwing injury. Fisher exact test compared the risk of injury between participants who pitched at least 4 years during the study and those who pitched less. Fisher exact tests were used to investigate risks of injury for pitching more than 100 innings in at least 1 calendar year, starting curveballs before age 13 years, and playing catcher for at least 3 years. Results: The cumulative incidence of injury was 5.0%. Participants who pitched more than 100 innings in a year were 3.5 times more likely to be injured (95% confidence interval = 1.16 to 10.44). Pitchers who concomitantly played catcher seemed to be injured more frequently, but this trend was not significant with the study sample size. Conclusion: Pitching more than 100 innings in a year significantly increases risk of injury. Playing catcher appears to increase a pitcher's risk of injury, although this trend is not significant. The study was unable to demonstrate that curveballs before age 13 years increase risk of injury. Clinical Relevance: The risk of a youth pitcher sustaining a serious throwing injury within 10 years is 5%. Limiting the number of innings pitched per year may reduce the risk of injury. Young baseball pitchers are encouraged to play other positions as well but might avoid playing catcher.

DOI： 10.1177/0363546510384224

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Pulmonary embolism is a serious complication after arthroscopy of the knee, about which there is limited information. We have identified the incidence and risk factors for symptomatic pulmonary embolism after arthroscopic procedures on outpatients. The New York State Department of Health Statewide Planning and Research Cooperative System database was used to review arthroscopic procedures of the knee performed on outpatients between 1997 and 2006, and identify those admitted within 90 days of surgery with an associated diagnosis of pulmonary embolism. Potential risk factors included age, gender, complexity of surgery, operating time defined as the total time that the patient was actually in the operating room, history of cancer, comorbidities, and the type of anaesthesia. We identified 374 033 patients who underwent 418 323 outpatient arthroscopies of the knee. There were 117 events of pulmonary embolism (2.8 cases for every 10 000 arthroscopies). Logistic regression analysis showed that age and operating time had significant doseresponse increases in risk (p < 0.001) for a subsequent admission with a pulmonary embolism. Female gender was associated with a 1.5-fold increase in risk (p = 0.03), and a history of cancer with a threefold increase (p = 0.05). These risk factors can be used when obtaining informed consent before surgery, to elevate the level of clinical suspicion of pulmonary embolism in patients at risk, and to establish a rationale for prospective studies to test the clinical benefit of thromboprophylaxis in high-risk patients.

DOI： 10.1302/0301-620X.93B1.25498

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background context: Recurrent herniation of the nucleus pulposus (HNP) frequently causes poor outcomes after lumbar discectomy. The relationship between obesity and recurrent HNP has not previously been reported. Purpose: The purpose of this study was to investigate the association of obesity with recurrent HNP after lumbar microdiscectomy. Study design: Retrospective Cohort. Patient sample: We reviewed all cases of one- or two-level lumbar microdiscectomy from L2-S1 performed by a single surgeon with a minimum follow-up of 6 months. Outcome measures: The primary clinical outcomes were evidence of recurrent HNP on magnetic resonance imaging (MRI) and need for repeat surgery. Methods: All patients with recurrent radicular pain or new neurological deficits underwent a postoperative MRI scan. Recurrent HNP was defined as a HNP at the same side and same level as the index procedure. Results: Seventy-five patients were included in the study. The average body mass index (BMI) was 27.6±4.6. Thirty-two patients received an MRI scan. The time from operation to repeat MRI scan varied widely (3 days to 15 months). Eight patients (10.7%) had recurrent HNP. Four patients had persistent symptoms requiring reoperation (5.3%). The mean BMI of patients with recurrent HNP was significantly higher than that of those without recurrence (33.6±5.1 vs. 26.9±3.9, p<.001). In univariate analysis, obese patients (BMI ≥30) were 12 times more likely to have recurrent HNP than nonobese patients (odds ratio [OR]: 12.46, 95% confidence interval [CI]: 2.25-69.90). Obese patients were 30 times more likely to require reoperation (OR: 32.81, 95% CI: 1.67-642.70). Age, sex, smoking, and being a manual laborer were not significantly associated with recurrent HNP. A logistic regression analysis supported the findings of the univariate analysis. In a survival analysis using a Cox proportional hazards model, the hazard ratio of recurrent HNP for obese patients was 17 (OR: 17.08, 95% CI: 2.85-102.30, p=.002). Conclusions: Obesity was a strong and independent predictor of recurrent HNP after lumbar microdiscectomy. Surgeons should incorporate weight loss counseling into their preoperative discussions with patients.

DOI： 10.1016/j.spinee.2010.02.021

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Context: Evaluation of the morphology and matrix composition of repair cartilage is a critical step toward understanding the natural history of cartilage repair and efficacy of potential therapeutics. In the current study, short-term articular cartilage repair (3 and 6 weeks) was evaluated in a rabbit osteochondral defect model treated with thrombin peptide (TP-508) using magnetic resonance imaging (MRI), quantitative T2 mapping, and Fourier transform-infrared imaging spectroscopy (FT-IRIS). Methods: Three-mm-diameter osteochondral defects were made in the rabbit trochlear groove and filled with either TP-508 plus poly-lactoglycolidic acid microspheres or poly-lactoglycolidic acid microspheres alone (placebo). Repair tissue and adjacent normal cartilage were evaluated at 3 and 6 weeks postdefect creation. Intact knees were evaluated by magnetic resonance imaging for repair morphology, and with quantitative T2 mapping to assess collagen orientation. Histological sections were evaluated by FT-IRIS for parameters that reflect collagen quantity and quality, as well as proteoglycan (PG) content. Results and Conclusion: There was no significant difference in volume of repair tissue at either time point. At 6 weeks, placebo repair tissue demonstrated longer T2 values (p<0.01) than TP-508 did. Although both placebo and TP-508 repair tissue demonstrated longer T2 values than adjacent normal cartilage did, the 6-week T2 values of the TP-508 specimens were closer to those of the adjacent normal cartilage than were the placebo values. FT-IRIS analysis demonstrated a significant increase in collagen content, integrity, and PG content of the TP-508 repair tissue from 3 to 6 weeks (p≤0.05). In addition, the collagen and PG content of the TP-508 samples were closer to normal cartilage at 3 weeks than were the placebo samples. Further, there was a significant inverse correlation between the T2 relaxation values and collagen orientation in the normal cartilage. However, there were no significant correlations between T2 relaxation values and any FT-IRIS parameter in the repair tissue. Together, the data demonstrate that MRI and FT-IRIS assessment of cartilage repair tissue provide molecular information that furthers understanding of the cartilage repair process.

DOI： 10.1089/ten.tec.2009.0020

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Studies of quality of life (QOL) in children with juvenile idiopathic arthritis (JIA) have focused on changes in musculoskeletal function secondary to arthritis. The role of visual functionality as a result of JIA-associated uveitis and its complications has not been examined. We evaluated the individual impact of physical and visual disability on QOL in children with and without uveitis. Methods: We administered patient-based questionnaires that measured visual function, physical function, and overall QOL to 27 children with JIA or idiopathic uveitis. Demographic data, assessed joint involvement, and reviewed medical records were recorded. Groups with and without uveitis were compared for differences in arthritis and uveitis disease characteristics with use of the Wilcoxon-Mann-Whitney, χ², and Fisher exact tests. Associations between physical or visual function, and overall QOL were measured with use of Pearson's correlation coefficient. Results: Of 27 patients, 85.2% had had arthritis and 51.9% had had uveitis. The group without uveitis had increased morning stiffness (p = 0.036). Patients with uveitis reported more eye redness (p = 0.033) and photophobia (p = 0.013) than those without uveitis. We observed moderate associations between overall QOL and visual function in the uveitis group (r = -0.579) and overall QOL and physical function in the nonuveitis group (r = -0.562). Conclusions: This study demonstrates that visual impairment is an important component of QOL in children with uveitis. It suggests that QOL studies should incorporate both visual and physical function measures in their analyses, especially because many children with JIA also suffer from uveitis and visual impairment.{A figure is presented}.

DOI： 10.1016/j.jaapos.2009.12.160

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Rationale: Pathological neovascularization is a critical component of diseases such as proliferative retinopathies, cancer and rheumatoid arthritis, yet much remains to be learned about the underlying causes. Previous studies showed that vascular endothelial growth factor (VEGF)-A activates the membrane-anchored metalloproteinase ADAM17 (a disintegrin and metalloproteinase 17) in endothelial cells, thereby stimulating crosstalk between VEGF receptor 2 and extracellular signal-regulated kinase. These findings raised interesting questions about the role of ADAM17 in angiogenesis and neovascularization in vivo. Objective: The objective of this study was to inactivate ADAM17 in endothelial cells or in pericytes to determine how this affects developmental angiogenesis, pathological retinal neovascularization and heterotopic tumor growth. Methods and Results: We generated animals in which floxed ADAM17 was removed by Tie2-Cre in endothelial cells, or by smooth muscle (sm) Cre in smooth muscle cells and pericytes. There were no evident developmental defects in either conditional knockout strain, but pathological retinal neovascularization and growth of heterotopically injected tumor cells was reduced in Adam17flox/flox/Tie2-Cre mice, although not in Adam17flox/flox/sm-Cre mice. Moreover, lack of ADAM17 in endothelial cells decreased ex vivo chord formation, and this could be largely restored by addition of the ADAM17 substrate HB-EGF (heparin-binding epidermal growth factor-like growth factor). Finally we found that ADAM17 is important for the VEGF receptor 2 stimulated processing of several receptors with known functions in endothelial cell biology. Conclusions: These results provide the first evidence for a role for ADAM17 in pathological neovascularization in vivo. Because ADAM17 does not appear to be required for normal developmental angiogenesis or vascular homeostasis, it could emerge as a good target for treatment of pathological neovascularization.

DOI： 10.1161/CIRCRESAHA.109.207415

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Pulmonary embolism (PE) complicates 1% to 10% of total joint arthroplasties and generally requires immediate anticoagulation. Low-molecular-weight heparins have supplanted unfractionated heparin as the treatment of choice for PE and hold a 1A recommendation from the American College of Chest Physicians for this indication. However, the complications of enoxaparin treatment begun in close proximity to arthroplasty surgery are not well described. We examined the records of 135 patients who underwent total joint arthroplasty, experienced an in-hospital PE, and received treatment with enoxaparin at therapeutic doses (1 mg/kg body weight). The type and frequency of complications were determined and classified as major or minor. Twenty-seven percent of patients experienced minor complications and 10% experienced major complications. The incidence of major bleeding was substantially higher than rates reported for nonsurgical patients. The overall complication rate of enoxaparin treatment is similar to the rate of complications reported for unfractionated heparin treatment in this setting, but the complications are less severe. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

DOI： 10.1007/s11999-009-1020-6

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to determine whether the mini-midvastus approach to total knee arthroplasty (TKA) results in differences in quadriceps muscle strength as well as previously cited advantages in a double blind prospective randomized trial. Twenty-seven patients (54 TKAs) scheduled for bilateral TKA were randomized to undergo mini-midvastus approach on one knee and standard approach on the other. Incision lengths were the same. Postoperative strength was determined by isokinetic and isometric peak torque testing. Range of motion, pain Visual analog scale, side-preference, and gait analysis were assessed preoperatively and postoperatively. The only significant difference in strength testing was increased isokinetic and isometric extension torque at 3 weeks postoperatively for the mini-midvastus approach. No differences between the mini-midvastus and standard approach were observed for stride length, stance time, pain Visual analog scale, or knee range of motion. The mini-midvastus approach has limited benefit compared to the standard approach for TKA.

DOI： 10.1016/j.arth.2010.04.003

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Meniscal and anterior cruciate ligament (ACL) injuries are common in college football athletes. The effect of meniscectomy and/or ACL surgery on the length of an athlete's career in the National Football League (NFL) has not been well examined. Hypothesis: Athletes with a history of meniscectomy or ACL surgery before the NFL combine have a shorter career than matched controls. Study Design: Case-control study; Level of evidence, 3. Methods: A database containing the injury history and career NFL statistics of athletes from 1987-2000 was used to match athletes with a history of meniscectomy and/or ACL surgery, and no other surgery or major injury, to controls without previous surgeries. Athletes were matched by position, year drafted, round drafted, and additional injury history. Results: Fifty-four athletes with a history of meniscectomy, 29 with a history of ACL reconstruction, and 11 with a history of both were identified and matched with controls. Isolated meniscectomy reduced the length of career in years (5.6 vs 7.0; P 5.03) and games played (62 vs 85; P 5.02). Isolated ACL surgery did not significantly reduce the length of career in years or games played. Comparing the athletes with meniscectomy or ACL reconstruction to athletes with combined ACL reconstruction and meniscectomy, a history of both surgeries, resulted in a shorter career in games started (7.9 vs 35.1; P<.01), games played (41 vs 63; P 5.07), and years (4.0 vs 5.8; P 5.08) than a history of either surgery alone. Conclusion: A history of meniscectomy, but not ACL reconstruction, shortens the expected career of a professional football player. A combination of ACL reconstruction and meniscectomy may be more detrimental to an athlete's durability than either surgery alone. Further research is warranted to better understand how these injuries and surgeries affect an athlete's career and what can be done to improve the long-term outcome after treatment.

DOI： 10.1177/0363546509349035

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Gender differences in hip and core strength and range of motion may contribute to the gender based variance in injury risk. This study was designed to test the primary hypothesis that hip and core strength, flexibility and lower extremity dynamic alignment differ in male and female soccer athletes. Ninety-eight collegiate soccer players (54 male, 44 female) participated in this study. Athletes were evaluated for hip range of motion, and hip and abdominal strength. Both male and female soccer players demonstrated limited hip rotation, with less hip internal rotation in males (p<0.0001), and poor abdominal core control, although the males are stronger (p=0.02). Overall hip ROM is shifted towards internal rotation in females compared to males. Female soccer players also have a significant side-to-side disparity in hip abductor strength (p<0.0001), not present in males. The shift in hip ROM towards internal rotation combined with the hip abductor imbalance may be associated with a position of ACL risk with internally rotated hips and valgus knees in female soccer players. Limitations in hip and core strength and range of motion may play a role in the disparity between the male and female rate of ACL injury.

DOI： 10.1055/s-0029-1225328

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Anterior cruciate ligament reconstruction is widely accepted as the treatment of choice for individuals with functional instability due to anterior cruciate deficiency. There remains little information on the epidemiology of anterior cruciate ligament reconstruction with regard to adverse outcomes such as hospital readmission and subsequent knee surgery. We sought to identify the frequency of anterior cruciate ligament reconstruction, the rates of subsequent operations and readmissions, and potential predictors of these outcomes. Methods: The Statewide Planning and Research Cooperative System (SPARCS) database, a census of all hospital admissions and ambulatory surgery in New York State, was used to identify anterior cruciate ligament reconstructions performed between 1997 and 2006. Patients with concomitant pathological conditions of the knee were included. The patients were tracked for hospital readmission within ninety days after the surgery and for subsequent surgery on either knee within one year. The risks of these outcomes were modeled with use of age, sex, comorbidity, hospital and surgeon volume, and inpatient or outpatient surgery as potential risk factors. Results: We identified 70,547 anterior cruciate ligament reconstructions, with an increase from 6178 in 1997 to 7507 in 2006. Readmission within ninety days after the surgery was infrequent (a 2.3% rate), but subsequent surgery on either knee within one year was much more common (a 6.5% rate). Patients were at increased risk for readmission within ninety days if they were over forty years of age, sicker (e.g., had a preexisting comorbidity), male, and operated on by a lowervolume surgeon. Predictors of subsequent knee surgery included being female, having concomitant knee surgery, and being operated on by a lower-volume surgeon. Predictors of a subsequent anterior cruciate ligament reconstruction included an age of less than forty years, concomitant meniscectomy or other knee surgery, and surgery in a lower-volume hospital. Conclusions: The rate of anterior cruciate ligament reconstruction has increased in frequency. Also, while anterior cruciate ligament reconstruction appears to be a safe procedure, the risk of a subsequent operation on either knee is increased among younger patients and those treated by a lower-volume surgeon or at a lower-volume hospital. Level of Evidence: Prognostic Level II. See Instructions to Authors for a complete description of levels of evidence.

DOI： 10.2106/JBJS.H.00539

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective: Carpometacarpal osteoarthritis (CMC OA) is highly prevalent in older adults, and is often unresponsive to medical treatment. Intra-articular Hylan G-F 20 has been shown to improve pain and function in patients with knee OA; however, its effectiveness in CMC OA is less clear. Methods: 32 patients with CMC OA were injected with Hylan G-F 20, once weekly for three consecutive weeks. Patients were assessed 4, 12, 20 and 26 weeks after the first injection. A last-value carried forward analysis was performed. Results: Average age was 64 years, (range 46-79), 69% were female and 97% Caucasian. Fifty-three percent had at least one previous corticosteroid injection in the affected CMC joint. At 26 weeks, mean visual analogue scale (VAS) for pain had improved significantly (15.2 mm; p-value = 0.006). Disabilities of the arm, shoulder and hand questionnaire (DASH) scores also improved significantly (12.6; p-value < 0.001). A DASH change of 10-14 is considered clinically meaningful. Neither key strength nor opposition grip strength improved. VAS scores for pain at 26 weeks showed good correlation with patient satisfaction (Spearman r = 0.52, p-value < 0.01). Adverse events potentially related to the injections included three episodes of post-injection pain and swelling, and one case of crystal proven pseudogout. Conclusion: Intra-articular Hylan G-F 20 injections reduced pain and improved function in patients with CMC OA at 26 weeks in this small open label study. Limitations of this study include its small, open label design. Larger randomized controlled trials are needed to confirm these results, and to determine predictors of response to treatment. Clinical trial registration: This study was approved by the Institutional Review Board at the Hospital for Special Surgery, New York, NY, USA and registered at www.clinicatrials.gov # NCT00198029.

DOI： 10.1185/03007990903084016

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Precise evaluation of acetabular cup version is necessary for patients with recurrent hip dislocation after THA. We retrospectively studied 42 patients, who underwent THAs, with multiple cross-table lateral radiographs and CT scans to determine whether radiographic or CT measurement of acetabular component version is more accurate. One observer measured cup version on all radiographs. CT scans were interpreted by one observer. Twenty radiographs were measured twice each by two observers to determine intraobserver and interobserver reliability. We implanted cups in four model pelvises using navigation and compared measurements of anteversion made with radiographs and CT scans. Intraclass correlation coefficients (ICC) for anteversion measurements of two observers were 0.9990 and 0.9998, respectively, when comparing measurements of identical radiographs (intraobserver). Paired values for two observers measuring the same radiograph had an ICC of 0.9686 (interobserver) compared with 0.7412 for measurements from serial radiographs of the same component. The ICC comparing radiographic versus CT-based measurements was 0.6981. CT measurements had stronger correlations with navigated values than radiographic measurements. Accuracy of anteversion measurements on cross-table radiographs depends on radiographic technique and patient positioning whereas properly performed CT measurements are independent of patient position. Level of Evidence: Level III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

DOI： 10.1007/s11999-009-0774-1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Recent evidence has linked long-term bisphosphonate use with insufficiency fractures of the femur in postmenopausal women. In this case-control study, we have identified a significant association between a unique fracture of the femoral shaft, a transverse fracture in an area of thickened cortices, and long-term bisphosphonate use. Further studies are warranted. Introduction: Although clinical trials confirm the anti-fracture efficacy of bisphosphonates over 3-5 years, the long-term effects of bisphosphonate use on bone metabolism are unknown. Femoral insufficiency factures in patients on prolonged treatment have been reported. Methods: We performed a retrospective case-control study of postmenopausal women who presented with low-energy femoral fractures from 2000 to 2007. Forty-one subtrochanteric and femoral shaft fracture cases were identified and matched by age, race, and body mass index to one intertrochanteric and femoral neck fracture each. Results: Bisphosphonate use was observed in 15 of the 41 subtrochanteric/shaft cases, compared to nine of the 82 intertrochanteric/femoral neck controls (Mantel-Haenszel odds ratio (OR), 4.44 [95% confidence interval (CI) 1.77-11.35]; P∈=∈0.002). A common X-ray pattern was identified in ten of the 15 subtrochanteric/shaft cases on a bisphosphonate. This X-ray pattern was highly associated with bisphosphonate use (OR, 15.33 [95% CI 3.06-76.90]; P∈<∈0.001). Duration of bisphosphonate use was longer in subtrochanteric/shaft cases compared to both hip fracture controls groups (P∈=∈0.001). Conclusions: We found a significantly greater proportion of patients with subtrochanteric/shaft fractures to be on long-term bisphosphonates than intertrochanteric/femoral neck fractures. Bisphosphonate use was highly associated with a unique X-ray pattern. Further studies are warranted.

DOI： 10.1007/s00198-008-0805-x

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The National Football League holds an annual combine where individual teams evaluate college football players likely to be drafted for physical skills, review players medical history and imaging studies, and perform a physical examination. Purpose: The purpose of this study was to test the effect of specific diagnoses and surgical procedures on the likelihood of playing and length of career in the league by position. Study Design: Cohort study; Level of evidence, 3. Methods: A database for all players reviewed at the annual National Football League Combine by the medical staff of 1 National Football League team from 1987 to 2000 was created, including each players orthopaedic rating, diagnoses, surgical procedures, number of games played, and number of seasons played in the National Football League. Athletes were grouped by position as follows: offensive backfield, offensive receiver, offensive line, quarterback, tight end, defensive line, defensive secondary, linebacker, and kicker. The percentage of athletes who played in the National Football League was calculated by position for each specific diagnosis and surgery. Results: The effect of injury on the likelihood of playing in the league varied by position. Anterior cruciate ligament injury significantly lowered the likelihood of playing in the league for defensive linemen (P = .03) and linebackers (P = .04). Meniscal injury significantly reduced the probability of playing (P < .05) and length of career (P = .002) for athletes in the defensive secondary. Shoulder instability had a significant effect on playing in the league for offensive (P = .03) and defensive linemen (P = .02), and shortened the length of career for defensive linemen (P = .016). Spondylolisthesis did not significantly reduce the chance of playing in the league for any position, while a history of spondylolysis had a significant effect for running backs (P = .01). Miscellaneous injuries (eg. acromioclavicular joint, knee medial collateral ligament, carpal fractures) had isolated position-specific effects. Conclusion: The significant injuries and diagnoses appear congruent with the position-specific demands placed on the athletes. This information is useful to physicians and athletic trainers caring for college football athletes as well as those assessing these athletes at the National Football League Combine.

DOI： 10.1177/0363546508329542

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Numerous studies have documented the effect of complete medial collateral ligament injury on anterior cruciate ligament loads; few have addressed how partial medial collateral ligament disruption affects knee kinematics. Purpose: To determine knee kinematics and subsequent change in anterior cruciate ligament load in a partial and complete medial collateral ligament injury model. Study Design: Controlled laboratory study. Methods: Ten human cadaveric knees were sequentially tested by a robot with the medial collateral ligament intact, in a partial injury model, and in a complete injury model with a universal force-moment sensor measuring system. Tibial translation, rotation, and anterior cruciate ligament load were measured under 3 conditions: anterior load (125 N), valgus load (10 N'm), and internal-external rotation torque (4 N'm; all at 0° and 30° of flexion). Results: Anterior and posterior translation did not statistically increase with a partial or complete medial collateral ligament injury at 0° and 30° of flexion. In response to a 125 N anterior load, at 0°, the anterior cruciate ligament load increased 8.7% (from 99.5 to 108.2 N; P = .006) in the partial injury and 18.3% (117.7 N; P < .001) in the complete injury; at 30°, anterior cruciate ligament load was increased 12.3% (from 101.7 to 114.2 N; P = .001) in the partial injury and 20.6% (122.7 N; P < .001) in the complete injury. In response to valgus torque (10 N'm) at 30°, anterior cruciate ligament load was increased 55.3% (30.4 to 47.2 N; P = .044) in the partial injury model and 185% (86.8 N; P = .001) in the complete injury model. In response to internal rotation torque (4 N'm) at 30°, anterior cruciate ligament load was increased 29.3% (27.6 to 35.7 N; P = .001) in the partial injury model and 65.2% (45.6 N; P < .001) in the complete injury model. The amount of internal rotation at 30° of flexion was significantly increased in the complete injury model 22.8°) versus the intact state (19.5°; P < .001). Conclusion: Partial and complete medial collateral ligament tears significantly increased the load on the anterior cruciate ligament. In a partial tear, the resultant load on the anterior cruciate ligament was increased at 30° of flexion and with valgus load and internal rotation torque. Clinical Relevance: Patients may need to be protected from valgus and internal rotation forces after anterior cruciate ligament reconstruction in the setting of a concomitant partial medial collateral ligament tear. This information may help clinicians understand the importance of partial injuries of the medial collateral ligament with a combined anterior cruciate ligament injury complex.

DOI： 10.1177/0363546508324969

記述言語：英語   掲載種別：研究論文（学術雑誌）  

This clinical study was performed to document the prevalence of deep vein thrombosis (DVT) after prosthetic shoulder replacement surgery. We prospectively followed 100 consecutive shoulder arthroplasty procedures (total shoulder replacement in 73 and hemiarthroplasty in 27) in 44 male and 56 female patients for 12 weeks (mean age, 67 years; range, 17-88 years). Risk factors for venous thromboembolic disease were assessed preoperatively and postoperatively. A 4-limb surveillance color flow Doppler ultrasound was performed at 2 days (100 patients) and 12 weeks (50 patients randomly selected) after surgery, and the presence and location of DVT were recorded. Postoperative symptomatic or fatal pulmonary emboli (PE) were also recorded. The overall prevalence of DVT was 13.0%, consisting of 13 DVTs in 12 patients. These included 6 ipsilateral and no contralateral upper extremity DVTs and 5 ipsilateral and 2 contralateral lower extremity DVTs. The prevalence of DVT was 10.0% (10/100) at day 2 after surgery and 6.0% (3/50) at week 12 after surgery. The incidence of symptomatic nonfatal PE was 2.0% (2/100), and that of fatal PE was 1.0% (1/100). Risk factors associated with venous thromboembolic disease did not reach statistical significance because of the small study population sample size. At our institution, the prevalence of DVT after reconstructive shoulder arthroplasty was 13.0%, a rate comparable to that after hip arthroplasty (10.3%) but lower than that after knee arthroplasty (27.2%). Shoulder arthroplasty surgeons should be aware of the potential risk of perioperative thromboembolic complications in both the acute and subacute postoperative periods.

DOI： 10.1016/j.jse.2008.07.011

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Many arthroplasty outcome studies use administrative data to evaluate complications and mortality. Most databases use International Classification of Diseases, Ninth Revision or Current Procedural Terminology codes, which lack laterality information. This study determined the frequency with which a second operation occurs on the same side after total hip arthroplasty (THA) and total knee arthroplasty (TKA) and identified variables associated with ipsilateral reoperation. In a hospital-based sample of patients undergoing multiple THA or TKA, the side of the index operation was compared with the side of the subsequent operation. Concordance was defined as the percentage of same-side reoperations. Overall concordance was 23% for THA and 22% for TKA, suggesting most reoperations were on the contralateral hip or knee. This study provides estimates of misclassification of reoperation after lower extremity arthroplasty when conducting orthopedic research with administrative data. Studies using these data should be aware of this limitation, and efforts should be made to limit reoperation to revision THA and TKA.

DOI： 10.1055/s-0030-1247721

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Intra-articular injections of hyaluronic acid products may eliminate pain, improve mobility and quality of life, and delay osteoarthritis progression. In this study, we evaluated the safety and efficacy of sodium hyaluronate injections given after knee arthroscopy. Forty-six patients with early osteoarthritis and a symptomatic meniscus tear were prospectively randomized into study (injection) and control groups and underwent knee arthroscopy. Study patients received 3 sodium hyaluronate injections after surgery. Study and control outcomes were compared 3 and 6 months after surgery. The injection patients had significantly less pain (visual analog scale) at 3-month follow-up and more flexion at 6-month follow-up. Tenderness, pain on motion, and crepitus were significantly more likely to be absent from injection patients at the 3- and 6-month follow-ups. Patients with osteoarthritis and a symptomatic meniscus tear may experience more pain relief and functional mobility after arthroscopic surgery plus hyaluronic acid injections than after arthroscopy alone.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to identify potential predictors of function and tendon healing after arthroscopic rotator cuff repair that will enable the orthopaedic surgeon to determine which patients can expect a successful outcome. Between 2003 and 2005, the Arthroscopic Rotator Cuff Registry was established to collect demographic, intraoperative, functional outcome, and ultrasound data prospectively on all patients who underwent primary arthroscopic rotator cuff repair. At total of 193 patients met the study criteria, and 127 (65.8%) completed the 2-year follow-up. The most significant independent factors affecting ultrasound outcome were age (odds ratio [OR], 1.08; 95% confidence interval [CI], 1.02-1.14; P = .006) and tear size (OR, 2.29; 95% CI, 1.55-3.38; P < .001). After adjustment for age and tear size, the intraoperative factors found to be significantly associated with a tendon defect were concomitant biceps procedures (OR, 11.39; 95% CI, 2.90-44.69; P < .001) and acromioclavicular joint procedures (OR, 3.85; 95% CI, 1.46-10.12; P = .006). In contrast to the ultrasound data, the functional outcome variables, such as satisfaction (OR, 3.92; 95% CI, 2.00-7.68; P < .001) and strength (OR, 10.05; 95% CI, 1.61-62.77; P = .01), had a greater role in predicting an American Shoulder and Elbow Surgeons score greater than 90. The progression from a single-tendon rotator cuff tear to a multiple-tendon tear with associated pathology increased the likelihood of tendon defect by at least 9 times, and therefore, earlier surgical intervention for isolated, single-tendon rotator cuff tears could optimize the likelihood of ultrasound healing and an excellent functional outcome.

DOI： 10.1016/j.jse.2008.05.045

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: The National Football League (NFL) holds an annual combine to evaluate college football athletes likely to be drafted for physical skills, to review their medical history, and to perform a physical examination. The athletes receive an orthopedic grade on their ability to participate in the NFL. The purpose of this study was to test the hypothesis that this orthopedic rating at the combine predicts the percent of athletes who play in the NFL and the length of their careers. Methods: A database for all athletes reviewed at the combine by the medical staff of one team from 1987 to 2000 was created and linked to a data set containing the number of seasons and the games played in the NFL for each athlete. Players were grouped by orthopedic grade: high, low, and orthopedic failure. The percent of players who played in the NFL and the mean length of their careers was calculated and compared for these groups. Results: The orthopedic grade assigned at the NFL combine correlated with the probability of playing in the league. Whereas 58% of athletes with a high grade and 55% of athletes with a low grade played at least one game, only 36% of athletes given a failing grade did so (P < 0.001). Players with a high grade had a mean career of 41.5 games compared with 34.2 games for players with a low grade and 19.0 games for orthopedic failures. Conclusion: This is the first study to report on the predictive value of a grading system for college athletes before participation in professional sports. Other professional sports may benefit from using a similar grading system for the evaluation of potential players.

DOI： 10.1249/MSS.0b013e31816f1c28

記述言語：英語   掲載種別：研究論文（学術雑誌）  

There are several techniques that have been described for distal biceps tendon repair but there is still controversy regarding the optimal technique. Our hypothesis is that the single-incision technique will have a similar complication rate and functionally equivalent restoration of function compared with the two-incision approach. A retrospective review of consecutive biceps tendon repairs was performed at one institution over a 5-year period. Thirty-six patients met the inclusion criteria and 26 were available for follow-up including subjective assessment, physical examination, and strength testing. Patients were divided into two groups based on the surgical approach utilized: 12 patients underwent single-incision repair and 14 had a two-incision repair. The average follow-up was 33 months (minimum 13; maximum 75). There were no statistically significant differences in regards to flexion strength or endurance, supination strength or endurance, or complication rates between the two techniques. In conclusion, both surgical techniques led to adequate restoration of strength with a low complication rate. Both techniques are safe to perform and should be guided by surgeon comfort with the approach.

DOI： 10.1007/s11420-008-9085-4

記述言語：英語   掲載種別：研究論文（学術雑誌）  

As a consequence of newly elevated standards for normal vitamin D levels, there is a renewed interest in vitamin D insufficiency and deficiency (<32 and <20 ng/ml, respectively) in the orthopedic patient population. This study tests the hypothesis that vitamin D insufficiency is comparably prevalent among both high- and low-energy fracture patients. A retrospective analysis of the medical records for 44 orthopedic trauma in-patients with non-vertebral fractures was conducted from June 1, 2006 to February 1, 2007. The obtained data included a 25-hydroxyvitamin D level, age, gender, and reason for admission; high-energy vs. low-energy fracture. Vitamin D insufficiency, 25(OH)D <32 ng/ml, was found in 59.1% of the patients. Significantly, more women (75%) than men (40%) were vitamin D insufficient among all fracture patients and specifically among high-energy fractures, 80% women insufficient vs. 25% men insufficient. In women, both high- and low-energy fractures present with vitamin D insufficiency (80% of high-energy fractures and 71.4% of low-energy fractures). In men, the mean vitamin D level was lower for low-energy fractures (16 ng/ml) compared to high-energy fractures (32 ng/ml). In addition, men with low-energy fractures were significantly older than men with high-energy fractures and women with low-energy fractures were also older. Statistically, more vitamin D insufficiency is seen in women and our results are consistent with the gender difference seen in the general population. Even among younger men who sustain a high-energy fracture, 25% are vitamin D insufficient. Women with fractures regardless of age or fracture energy level have low vitamin D levels. Levels of 25(OH)D should be measured in all orthopedic trauma patients and the American Society for Bone and Mineral Research and National Osteoporosis Foundation currently recommend that vitamin D levels should be corrected.

DOI： 10.1007/s11420-008-9083-6

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: To test the hypothesis that regional variations in supraspinatus tendon vascularity exist and can be imaged and quantified in asymptomatic individuals by using contrast material-enhanced ultrasonography (US). Materials and Methods: After institutional review board approval and informed consent were obtained, 31 volunteers aged 22-65 years (mean age, 41.5 years) underwent lipid microsphere contrast-enhanced shoulder US performed with an L8-4 transducer operating in contrast harmonic mode and a mechanical index of 0.07 in a HIPAA-compliant protocol. Images were obtained in the volunteers at rest and after exercise. Quantitative analysis was performed by using the time-enhancement postcontrast data derived from four regions of interest (ROIs): bursal medial, articular medial, bursal lateral, and articular lateral. Two 2-minute acquisitions were performed after each contrast material bolus. Baseline enhancement and peak enhancement for each ROI were estimated from these acquisitions. Baseline gray-scale and power Doppler US images of the supraspinatus tendon were obtained by using an L12-5 transducer. The Mann-Whitney nonparametric test was used to test for significant differences between ROIs in all volunteers. Results: In the volunteers at rest before exercise, significant variations in regional enhancement between the articular medial zone and both the bursal medial zone (P = .002) and the bursal lateral zone (P = .003) were observed. Differences in enhancement between the articular medial and articular lateral zones approached significance. Greater differentiation (P < .001) was observed after exercise, with a significant increase in apparent enhancement in each ROI in all volunteers. Conclusion: This study revealed the spatial distribution of the blood supply to the supraspinatus tendon in asymptomatic individuals. The addition of exercise to the protocol resulted in a significantly increased level of enhancement compared with that at rest and enabled more sensitive assessment of intratendinous and peritendinous vascularity.

DOI： 10.1148/radiol.2483071400

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Anticoagulation for thromboprophylaxis after THA and TKA has not been confirmed to diminish all-cause mortality. We determined whether the incidence of all-cause mortality and pulmonary embolism in patients undergoing total joint arthroplasty differs with currently used thromboprophylaxis protocols. We reviewed articles published from 1998 to 2007 that included 6-week or 3-month incidence of all-cause mortality and symptomatic, nonfatal pulmonary embolism. Twenty studies included reported 15,839 patients receiving low-molecular-weight heparin, ximelagatran, fondaparinux, or rivaroxaban (Group A); 7193 receiving regional anesthesia, pneumatic compression, and aspirin (Group B); and 5006 receiving warfarin (Group C). All-cause mortality was higher in Group A than in Group B (0.41% versus 0.19%) and the incidence of clinical nonfatal pulmonary embolus was higher in Group A than in Group B (0.60% versus 0.35%). The incidences of all-cause mortality and nonfatal pulmonary embolism in Group C were similar to those in Group A (0.4 and 0.52, respectively). Clinical pulmonary embolus occurs despite the use of anticoagulants. Group A anticoagulants were associated with the highest all-cause mortality of the three modalities studied. Level of Evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

DOI： 10.1007/s11999-007-0092-4

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Risk factors for revision surgery and hospitalization following rotator cuff repair (RCR) have not been clearly identified. We hypothesized patient factors and surgeon and hospital volume independently contribute to the risk of readmission within 90 days and revision RCR within one year. Using the SPARCS database, we included patients undergoing primary RCR in New York State between 1997 and 2002. These patients were tracked for readmission within 90 days and revision RCR within 1 year. A generalized estimating equation was developed to determine whether patient factors, surgeon volume, or hospital volume were independent risk factors for the above outcome measures. The total annual number of RCR increased from 6,656 in 1997 to 10,128 in 2002. Ambulatory cases increased from 57% to 82% during this time period. Independent risk factors for readmission within 90 days included increasing age and increased number of comorbidities. Independent risk factors for revision RCR included increasing age, increased comorbidity, and lower surgeon volume. Hospital volume had a minimal effect on either outcome measure. The shift toward out-patient surgery mirrors the shift from open to arthroscopic rotator cuff repair. The finding that surgeon volume is a predictor of revision RCR reflects the findings in other orthopaedic procedures. Level of Evidence: Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

DOI： 10.1007/s11999-008-0116-8

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Between December 1996 and April 2003, 26 consecutive femoral component revisions in 24 patients were performed with an extensively hydroxyapatite- coated femoral stem. Two patients were lost to follow-up, and two patients died of unrelated causes. Of the 22 femoral revisions in 20 patients, there was a 0% incidence of mechanical loosening at average follow-up of 3.2 years (2-6.3 years). The Harris Hip Score improved from 59 (36 to 83) to 95 (84 to 100) postoperatively (p∈<∈0.001). Rate of revision was 18.2% (4.5% for sepsis, 9.1% for instability, and 4.5% for polyethelene wear). All 22 femoral components had evidence of bone ingrowth. The extensively coated hydroxyapatite stem in this series produced excellent clinical results with a low incidence of thigh pain (4.5%) and severe stress shielding (4.5%).

DOI： 10.1007/s11420-007-9068-x

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The natural history of the blood supply to the rotator cuff and its role in the etiology of rotator cuff disease has not been definitively established. To date, there has not been an in-vivo dynamic assessment of the baseline vascularity of the asymptomatic rotator cuff. This study was designed to test the hypothesis that regional variations in supraspinatus tendon vascularity exist with an age-dependent decrease in asymptomatic individuals with intact rotator cuffs. Lipid microsphere, contrast-enhanced ultrasound shoulder examinations were done in 31 patients with a mean age of 41.5 years (range, 22-65 years). Images were obtained at baseline, after contrast administration at rest, and after contrast administration following exercise to visualize the intratendinous blood flow to the supraspinatus tendon. Qualitative and quantitative analysis was performed by determining 4 regions of interest (bursal medial, articular medial, bursal lateral, and articular lateral) with quantification and analysis software (QLAB Philips, Andover, MA) to examine each region of interest and normalize data for interpretation of the mean intensity per pixel. A statistically significant decrease in blood flow to the supraspinatus tendon with age was observed in a comparative analysis of patients aged younger than 40 and older than 40, (P < .05 for all 4 zones after exercise and for the bursal medial, articular medial, and bursal lateral zones after exercise; P = .07 for the articular lateral zone after exercise). A statistically significant increase in blood flow with exercise was observed in an analysis of all patients (P < .001). The age-related decrease in the vascular supply of the tendon observed in this study is consistent with published reports demonstrating an increasing prevalence of rotator cuff pathology with age and may predispose to the development of rotator cuff tendinopathy and, ultimately, attritional tears.

DOI： 10.1016/j.jse.2007.07.004

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: The goals of this assessment were to elicit rheumatoid arthritis patients' expectations of metacarpophalangeal joint arthroplasty and to explore how preoperative preferences might influence patients' surgical decision making. METHODS: Rheumatoid arthritis patients who were appropriate metacarpophalangeal joint arthroplasty candidates were assessed by surgeons at three centers. Patients answered a questionnaire on expectations for metacarpophalangeal joint arthroplasty before deciding on whether to actually undergo the procedure. RESULTS: Of 56 eligible patients, 41 percent decided to have surgery, 48 percent decided against it, and 11 percent were undecided. Among the 48 patients without previous metacarpophalangeal joint arthroplasty, improving hand appearance and hand function were most often cited by patients as "very important." The nonsurgical group was more likely to be most bothered by hand weakness (32 percent versus 0 percent, p = 0.03), whereas the surgical group was more likely to be bothered by poor function (62 percent versus 23 percent, p = 0.01). The nonsurgical patients were more likely to value their own opinion as most important in the surgical decision-making process (59 percent versus 29 percent, p = 0.04). Both groups overestimated the risk of serious complications, but the surgical group was less likely to believe postoperative rehabilitation would be difficult (odds ratio, 0.2; 95% CI, 0.1 to 0.9). CONCLUSIONS: Patients who are eligible for metacarpophalangeal arthroplasty but decline surgery appear to have different baseline expectations and preferences than those who choose surgery. Patients who refuse surgery may use information differently in their decision-making process. Understanding and addressing patients' expectations and preferences preoperatively could help identify those patients who would most likely benefit from surgery.

DOI： 10.1097/01.prs.0000295376.70930.7e

記述言語：英語   掲載種別：研究論文（学術雑誌）  

STUDY DESIGN: Controlled laboratory study. OBJECTIVES: To quantify phase duration and lower extremity muscle activation and alignment during the most common types of soccer kick-the instep kick and side-foot kick. A second purpose was to test the hypotheses that different patterns of lower extremity muscle activation occur between the 2 types of kicks and between the kicking limb compared to the support limb. BACKGROUND: Soccer players are at risk for lower extremity injury, especially at the knee. Kicking the soccer ball is an essential, common, and distinctive part of a soccer player's activity that plays a role in soccer player injury. Regaining the ability to kick is also essential for soccer athletes to return to play after injury. METHODS: Thirteen male soccer players underwent video motion analysis and electromyography (EMG) of 7 muscles in both the kicking and supporting lower extremity (iliacus, gluteus maximus, gluteus medius, vastus lateralis, vastus medialis, hamstrings, gastrocnemius) and 2 additional muscles in the kicking limb only (hip adductors, tibialis anterior). Five instep and 5 side-foot kicks were recorded for each player. Analysis-of-variance models were used to compare EMG activity between type of kicks and between the kicking and nonkicking lower extremity. RESULTS: Five phases of kicking were identified: (1) preparation, (2) backswing, (3) limb cocking, (4) acceleration, and (5) follow-through. Comparing the kicking limb between the 2 types of kick, significant interaction effects were identified for the hamstrings (P = .02) and the tibialis anterior (P<.01). Greater activation of the kicking limb iliacus (P<.01), gastrocnemius (P<.01), vastus medialis (P = .016), and hip adductors (P<.01) occurred during the instep kick. Significant differences were seen between the kicking limb and the support limb for all muscles during both types of kick. CONCLUSIONS: Certain lower extremity muscle groups face different demands during the soccer instep kick compared to the soccer side-foot kick. Similarly, the support limb muscles face different demands than the kicking limb during both kicks. Better definition of lower extremity function during kicking provides a basis for improved insight into soccer player performance, injury prevention, and rehabilitation.

DOI： 10.2519/jospt.2007.2255

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Meniscal allograft transplantation has become a viable surgical alternative for a select group of patients with deficient or irreparable menisci. Subjective results are encouraging; long-term success, durability, and safety of allograft meniscal transplantation are uncertain. Purposes: To evaluate a novel hydrogel meniscal replacement implant in an ovine model and assess chondroprotective effects of this hydrogel meniscal replacement using several validated outcome measures. Study Design: Controlled laboratory study. Methods: Fourteen skeletally mature sheep underwent hydrogel meniscal replacement; 45 additional animals had previously undergone 1 of 3 operations: lateral meniscectomy (24), meniscal allograft transplant (17), and sham (4). Animals were sacrificed at 2, 4, or 12 months. Cartilage was assessed by magnetic resonance imaging, gross inspection, biomechanical testing, and semiquantitative histological analysis. Results: There were no differences between the sham operation and nonoperated control limbs. Compared with meniscectomy, hydrogel meniscal replacement resulted in significantly decreased cartilage degeneration with all outcome parameters (P <.05). Compared with nonoperated control limbs, hydrogel meniscal replacements demonstrated no significant differences at 2 months in any category. By 4 months, hydrogel limbs demonstrated significantly greater cartilage degeneration than did nonoperated control limbs in all categories. Compared with meniscal allograft transplantation animals, hydrogel meniscal replacements demonstrated no differences at 2 months but had significantly increased cartilage degeneration in the peripheral zone of the tibial plateau at 4 months (P <.05). At 1 year, all hydrogel implants had developed complete radial splits in the posterior third of the implant. Conclusion: Although promising preliminary results for hydrogel meniscal replacement were seen at early time points, significant cartilage degeneration and implant failure were seen at 1 year, and overall performance was worse than was allograft transplantation. Improvements in hydrogel material properties and surface characteristics and more accurate size matching may improve outcomes. Clinical Relevance: Improvements in the hydrogel material properties and surface characteristics and more accurate size matching may lead to the use of hydrogel implants in humans.

DOI： 10.1177/0363546506292848

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The Contour cage introduced in 1999 was designed to improve fixation and provide a surface for bone ongrowth. To determine whether the rates of radiographic loosening and/or revision have been reduced with the Contour design, we retrospectively reviewed the medical records and radiographs of 29 patients (average age, 68.1 years) undergoing 31 acetabular revisions with a Contour cage. The minimum followup was 24 months (mean 30 months, range, 24-58 months). Based on the Paprosky classification, two hips were Type 2B, seven were Type 3A, and 22 were Type 3B. Two hips (7%) were revised for loosening; one of these two was also infected. An additional five hips (16%) had signs of radiographic loosening. The mean Harris hip score improved from 45 to 80; functional scores improved less than the pain scores. Only 14 hips (45%) had an excellent or good clinical result and three of these 14 hips had radiographic signs of loosening; presuming these three hips eventually fail, only 35% of the hips had a good or excellent result. We found an association between number of previous surgeries and radiographic loosening and revision. Our data suggest the Contour cage offers little advantage over other antiprotrusio cages and highlight the substantial limitations of current methods available for treating patients with extensive acetabular bone loss.

DOI： 10.1097/01.blo.0000246533.37006.b0

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The role of surface finish on the survivorship of cemented femoral stems continues to be debated. A total of 34 proximally roughened cemented stems were implanted in 33 consecutive patients undergoing total hip arthroplasty by a single surgeon. An alarmingly high failure rate was observed, prompting a retrospective chart review, analysis of radiographs, and evaluation of retrieved stems and pathological specimens. Nineteen patients were available with more than two years follow-up. Of these 19 patients, nine stems had failed (47%) due to severe osteolysis and stem loosening. Failures were significantly more common in the male gender (p<0.005), and young (p=0.05), tall (p<0.002), and heavy patients (p<0.004). All failed revised hips showed severe metallosis, with both gross and microscopic evidence of metallic shedding from the stems. Our findings suggest that this proximally roughened stem is susceptible to early failure. Failure is characterized by stem debonding, subsidence within the cement mantle, shedding of metallic and cement particles due to fretting, and rapidly progressive osteolysis. These findings have been observed with other rough surface finish cemented stems.

DOI： 10.1007/s00264-005-0066-7

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Deep venous thrombosis and pulmonary embolism after shoulder arthroplasty are not well described. We sought to identify the frequency of deep venous thrombosis and pulmonary embolisms in patients after shoulder arthroplasties to compare these rates with the frequency of deep venous thrombosis and pulmonary embolisms among patients who had total hip and total knee arthroplasties, and to identify associated risk factors. The New York State Department of Health Statewide Planning and Research Cooperative System database was used to identify hospital admissions of patients having shoulder, hip, or knee arthroplasties between 1985 and 2003 with or without an associated diagnostic code for deep venous thrombosis or pulmonary embolism. This resulted in a retrospective cohort of 328,301 procedures. The frequency of deep venous thrombosis was 5.0 per 1000 procedures for shoulder arthroplasties compared with 15.7 for hip arthroplasties and 26.9 for knee arthroplasties. The frequency of pulmonary embolisms was 2.3 for shoulder arthroplasties, 4.2 for hip arthroplasties, and 4.4 for knee arthroplasties. Increasing age, trauma, and cancer were risk factors for thromboembolic events after shoulder arthroplasties. Although the absolute rates of thromboembolic complications were less in patients who had shoulder arthroplasties compared with those of patients who had lower extremity procedures, a larger percentage of these complications were pulmonary embolisms. Perioperative antithrombotic prophylaxis may be beneficial to reduce the frequency of deep venous thrombosis and pulmonary embolisms among patients having shoulder arthroplasties, particularly in higher-risk groups.

DOI： 10.1097/01.blo.0000194679.87258.6e

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Study Design. A retrospective review of lumbar total disc replacement (TDR) radiographs. Objective. To determine the error and variability in measuring TDR radiographic range of motion (ROM). Summary of Background Data. Motion preservation is the driving force behind lumbar TDR technology. In the recent literature, sagittal radiographic TDR ROM as low as 2° has been reported. In these studies, ROM was determined by using the Cobb method to measure TDR sagittal alignment angles in flexion-extension lateral radiographs. However, previous studies in the spinal deformity literature have shown that the Cobb method is very susceptible to measurement error. Methods. There were 5 observers, including 2 attending orthopedic spine surgeons, 1 spine fellow, 1 fifth-year resident, and 1 fourth-year resident, who measured the ROM of 50 ProDisc II (Synthes Spine Solutions, New York, NY) TDRs on standard flexion-extension lumbar spine radiograph sets. Repeated measurements were made on 2 occasions using the Cobb method. Measurement variability was calculated using 3 statistical methods. Results. The 3 statistical methods resulted in extremely similar values for TDR ROM observer variability. Overall, the intraobserver variability of TDR ROM measurement was ±4.6°, and interobserver variability was ±5.2°. Conclusions. To be 95% certain that an implanted TDR prosthesis has any sagittal motion, a ROM of at least 4.6° must be observed, which is the upper limit of intraobserver measurement variability for a TDR with a true ROM of 0°. To be 95% certain that a change in TDR ROM has occurred between 2 measurements by the same observer, a change in ROM of at least 9.6° must be observed (the entire range of ±4.6° intraobserver variability). ROM measurement variability should be considered when evaluating the success or failure of motion preservation in lumbar TDR.

DOI： 10.1097/01.brs.0000216452.54421.ea

記述言語：英語  

Objective: To identify the frequency of injury in youth baseball, risk factors for these injuries, and possible prevention measures to reduce the frequency or severity of these injuries. Data Sources: Information was collected from all known epidemiologic and intervention studies published in the peer-reviewed medical and scientific literature as it applies to youth baseball injuries. Main Results: The frequency and severity of youth baseball injuries have remained relatively consistent over time. Risk factors for many injuries have been understudied and the study designs used for much of this research have been less than optimal. Several effective prevention measures have been identified, such as batting helmets, face shields, softer baseballs, and breakaway bases. Conclusions: Baseball is a relatively safe sport compared to many contact sports, but injuries do still occur. Future research should focus on determining the optimum pitching motion for both arm safety and performance, as well as systematically studying other potential safety improvements such as restrictions against breaking pitches.

DOI： 10.1159/000085340

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Acute and chronic cartilage injury of the knee has an important impact on prognosis. The validity of the classification of such injuries is critical for prospective multicenter studies. The agreement among multiple surgeons at different institutions for articular cartilage lesions has not been established. Hypothesis: Arthroscopic classification of articular cartilage lesions is reliable and reproducible and can be used for multicenter studies involving multiple surgeons. Study Design: Cohort study (diagnosis); Level of evidence, 1. Methods: A total of 6 surgeons from 5 centers reviewed 31 videos of articular cartilage lesions. With grade 2 and grade 3 combined for the analysis, observed agreement ranged from 81% to 94%, and kappa ranged from 0.34 to 0.87. An additional 22 videos comprising grade 2 and grade 3 lesions were analyzed, and the observed agreement was 80%, with an overall kappa of 0.47. Conclusion: Arthroscopic grading of articular cartilage lesions is reproducible among surgeons at different centers. Clinical Relevance: Articular cartilage lesions can be reliably classified among surgeons at different sites. Such reliability is important for multicenter clinical research studies involving arthroscopic knee surgery.

DOI： 10.1177/0363546505275129

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to compare MRI scanogram with traditional radiographic methods for measurement of limb length. The authors hypothesized that MRI scanogram would be as reliable and accurate as radiographic scanogram in measurement of limb length without exposing patients to ionizing radiation. Twelve cadaveric femurs were measured using AP conventional radiographic scanogram, CT scanogram, MRI scanogram, and electronic caliper. Three orthopaedists performed two separate measurements using each technique. Intraobserver and interobserver variability was assessed for each of the three radiographic techniques. Accuracy was assessed by comparison of radiographic measurements to electronic caliper measurements of femur length. The reliability of all three radiographic limb length measurement techniques was excellent (ICC > 0.99). The accuracy of plain radiographic scanogram was slightly superior to CT scanogram and MRI scanogram. The mean absolute differences for radiographic, CT, and MRI scanograms compared with the gold standard, direct caliper measurement, were 0.52 mm, 0.68 mm, and 2.90 mm, respectively. All three scanogram techniques showed excellent reliability and accuracy. Radiographic scanogram remains the gold standard for leg length measurement. MRI scanogram is slightly less accurate compared with radiographic scanogram, but it does not use ionizing radiation. MRI scanogram merits clinical study and comparison with the traditional radiographic scanogram method for measurement of limb length.

DOI： 10.1097/01.bpo.0000173246.12184.a5

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Epidemiologic studies have demonstrated substantial variations in per capita rates of many surgical procedures, including rotator cuff repair. The purpose of the current study was to characterize orthopaedic surgeons' attitudes concerning medical decision-making about rotator cuff surgery and to investigate the associations between these beliefs and reported surgical volumes. Methods: A survey was mailed to randomly selected orthopaedic surgeons listed in the American Academy of Orthopaedic Surgeons directory. Only individuals who had treated patients for a rotator cuff tear, or had referred patients for such treatment, within the previous year were asked to complete the two-page survey. The survey comprised fifteen questions regarding clinical opinion, including four regarding hypothetical cases. Clinical agreement was defined as >80% of the respondents answering similarly. Results: Of the 1100 surveys that were mailed, 539 were returned (a response rate of 49%). Of the 539 respondents, 316 (58.6%) had treated or referred patients with a rotator cuff tear in the previous year. There was a significant negative correlation between the surgeon's estimation of the failure rate of cuff repairs in the United States and that surgeon's procedure volume (r = -0.21, p = 0.0003), indicating that surgeons with a lower procedure volume are more pessimistic about the results of surgery than are those with a higher procedure volume. Arthroscopic, mini-open, and open cuff repairs were preferred by 14.5%, 46.2%, and 36.6% of the respondents, respectively. Surgeons who performed a higher volume of procedures were less likely to perform open surgery (p < 0.0001). There was clinical agreement regarding only four of the nine clinical questions and none of the four questions about the hypothetical vignettes. Conclusions: We found significant variation in surgical decision-making and a lack of clinical agreement among orthopaedic surgeons about rotator cuff surgery. There was a positive correlation between the volume of procedures performed by the surgeon and the surgeon's perception of outcome, with surgeons who had a higher procedure volume being more enthusiastic about rotator cuff surgery than those who had a lower procedure volume.

DOI： 10.2106/JBJS.D.02944

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose of review: Surgical and nonsurgical treatment of arthritis is a rapidly developing and evolving field. It is vital for clinicians to keep up on the latest advances. This review focuses on clinical trials or large prospective studies over the past year that evaluated orthopedic surgical techniques for the treatment of arthritis and new nonsurgical therapies that may prevent the need for surgical intervention. Increasing attention has also been focused on the relation between surgeon or hospital case load and the quality of outcomes after surgery. Recent findings: No fewer than 10 studies have been published over the past year evaluating the use of hyaluronic acid (a viscosupplement) or corticosteroid injections as alternative treatments to knee arthroscopy for osteoarthritis of the knee. Joint replacement research has explored minimally invasive and computer-guided or robot-guided joint replacement surgery, the best, operative choice for advanced1 shoulder arthritis (hemiarthroplasty compared with total shoulder replacement), the role of patellar resurfacing during total joint replacement, and the use of: bisphosphonates for retention of bone density after joint replacement. Summary: The increasing attention on high-quality surgical trials should continue to improve surgical options based on sound research for patients with arthritis. Future research should continue to improve the available high-quality research for treatment choices.

DOI： 10.1097/01.bor.0000154189.82451.66

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to evaluate the relationship between increasing hospital volume and the following outcomes for total shoulder arthroplasties done in the state of New York: length of stay, hospital costs, readmission within 60 days, revision surgery within 24 months, and death within 60 days. The Statewide Planning and Research Cooperative System (SPARCS) database from the New York State Department of Health, a census of all hospital discharges in the state, was used to evaluate the relationship between hospital volume and outcomes for total shoulder arthroplasties for 1996 to 1999. One thousand three hundred seven total shoulder arthroplasties were done in New York from 1996 to 1999. Nearly 1/2 were done at the five highest-volume hospitals. Middle-volume hospitals has the least lengths of stay and hospital costs. Independent of age and comorbidities, patients at hospitals with greater volumes of total shoulder arthroplasties were at reduced risk of patients being readmitted within 60 days. No other outcomes were significantly associated with hospital volume. The finding that greater hospital volume decreases risk of readmission may have important public health implications, but additional research is needed before implementing policy changes. Level of Evidence: Prognostic study, Level II-1 (retrospective study). See the Guidelines for Authors for a complete description of levels of evidence.

DOI： 10.1097/01.blo.0000150571.51381.9a

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Reported rates and types of ice hockey injuries have been variable. Ice hockey combines tremendous speeds with aggressive physical play and therefore has great inherent potential for injury. Purpose: To identify rates and determinants of injury in American men's collegiate ice hockey. Study Design: Prospective cohort study. Methods: Data were collected from 8 teams in a Division I athletic conference for 1 season using an injury reporting form specific for ice hockey. Results: There were a total of 113 injuries in 23 096 athlete exposures. Sixty-five percent of injuries occurred during games, although games accounted for only 23% of all exposures. The overall injury rate was 4.9 per 1000 athlete exposures (13.8 per 1000 game athlete exposures and 2.2 per 1000 practice athlete exposures). Collision with an opponent (32.8%) or the boards (18.6%) caused more than half of all injuries. Concussion (18.6%) was the most common injury, followed by knee medial collateral ligament sprains, acromioclavicular joint injuries, and ankle sprains. Conclusions: The risk of injury in men's collegiate ice hockey is much greater during games than during practices. Concussions are a main cause for time lost and remain an area of major concern.

DOI： 10.1177/0363546504267349

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Although there is evidence that very active, young patients are better served with anterior cruciate ligament reconstruction, there is a lack of objective data demonstrating that future knee injury is prevented by these procedures. Hypothesis: Anterior cruciate ligament reconstruction protects against reinjury of the knee that would require reoperation. Study Design: Retrospective cohort study. Methods: A cohort of 6576 active-duty army personnel who had been hospitalized for anterior cruciate ligament injury from 1990 to 1996 were identified. Using the Total Army Injury and Health Outcomes Database, the authors followed these individuals for up to 9 years and collected clinical, demographic, and occupational data. These data were evaluated with bivariate and multivariable analyses to determine the effect of anterior cruciate ligament reconstruction on the rate of knee reinjury that required operation. Results: Of the 6576 study subjects, 3795 subjects (58%) underwent anterior cruciate ligament reconstruction and 2781 (42%) did not. The rate of reoperation was significantly lower among the anterior cruciate ligament reconstruction group (4.90/100 person-years) compared with those treated conservatively (13.86/100 person-years; P < .0001). Proportional hazard regression analyses adjusted for age, race, sex, marital status, education, and physical activity level confirmed that anterior cruciate ligament reconstruction was protective against meniscal and cartilage reinjury (P < .0001). Secondary medial meniscal injury was more common than secondary lateral meniscal injury (P < .003). Younger age was the strongest predictor of failure of conservative management leading to late anterior cruciate ligament reconstruction (P < .0001). Conclusions: Anterior cruciate ligament reconstruction protected against reoperation in this young, active population; younger subjects were more likely to require late anterior cruciate ligament reconstruction. Clinical Relevance: Strong consideration should be given to anterior cruciate ligament reconstruction after anterior cruciate ligament injury in young, active individuals.

DOI： 10.1177/0363546504265006

記述言語：英語   掲載種別：研究論文（学術雑誌）  

A group of 42 primary total hip arthroplasties performed through an abridged surgical incision (group 1) was prospectively compared to a cohort of 42 primary total hip arthroplasties performed through a standard surgical incision (group 2). The length of the incision was 8.8 ± 1.5 cm for group 1 and 23.0 ± 2.1 cm for group 2. The groups were not significantly different with respect to age, height, preoperative Harris Hip scores (HHS), estimated blood loss, or length of hospital stay (P>.05). Group 1 patients had a lower body mass index than group 2 patients (P<.01). Length of surgery was slightly less for group I (P = .02). A 0% incidence was found of infection, nerve palsy, component malposition, and aseptic loosening in both groups. No dislocations occurred in group 1, and one dislocation occurred in group 2. Patients in group 1 have expressed considerable enthusiasm regarding the cosmetic appearance of the surgical incisions, and their postoperative HHS are slightly higher than those of group 2 (P = .042). Total hip arthroplasty can be performed safely and effectively through an abridged surgical incision, but this investigation confirms no dramatic clinical benefit other than cosmetic appeal.

DOI： 10.1016/j.arth.2003.12.070

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Baseball pitching must be performed with correct technique if injuries are to be avoided and performance maximised. High‐speed video analysis is accepted as the most accurate and objective method for evaluation of baseball pitching mechanics. The aim of this research was to develop an equivalent qualitative analysis method for use with standard video equipment. A qualitative analysis protocol (QAP) was developed for 24 kinematic variables identified as important to pitching performance. Twenty male baseball pitchers were videotaped using 60 Hz camcorders, and their technique evaluated using the QAP, by two independent raters. Each pitcher was also assessed using a 6‐camera 200 Hz Motion Analysis system (MAS). Four QAP variables (22%) showed significant similarity with MAS results. Inter‐rater reliability showed agreement on 33% of QAP variables. It was concluded that a complete and accurate profile of an athlete's pitching mechanics cannot be made using the QAP in its current form, but it is possible such simple forms of biomechanical analysis could yield accurate results before 3‐D methods become obligatory.

DOI： 10.1080/14763140308522819

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Joint pain is thought to be an early sign of injury to a pitcher. Objective: To evaluate the association between pitch counts, pitch types, and pitching mechanics and shoulder and elbow pain in young pitchers. Study Design: Prospective cohort study. Methods: Four hundred and seventy-six young (ages 9 to 14 years) baseball pitchers were followed for one season. Data were collected from pre- and postseason questionnaires, injury and performance interviews after each game, pitch count logs, and video analysis of pitching mechanics. Generalized estimating equations and logistic regression analysis were used. Results: Half of the subjects experienced elbow or shoulder pain during the season. The curveball was associated with a 52% increased risk of shoulder pain and the slider was associated with an 86% increased risk of elbow pain. There was a significant association between the number of pitches thrown in a game and during the season and the rate of elbow pain and shoulder pain. Conclusions: Pitchers in this age group should be cautioned about throwing breaking pitches (curveballs and sliders) because of the increased risk of elbow and shoulder pain. Limitations on pitches thrown in a game and in a season can also reduce the risk of pain. Further evaluation of pain and pitching mechanics is necessary.

DOI： 10.1177/03635465020300040201

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The throwing shoulder in pitchers frequently exhibits a paradox of glenohumeral joint motion, in which excessive external rotation is present at the expense of decreased internal rotation. The object of this study was to determine the role of humeral head retroversion in relation to increased glenohumeral external rotation. Glenohumeral joint range of motion and laxity along with humeral head and glenoid version of the dominant versus nondominant shoulders were studied in 25 professional pitchers and 25 nonthrowing subjects. Each subject underwent a computed tomography scan to determine bilateral humeral head and glenoid version. The throwing group demonstrated a significant increase in the dominant shoulder versus the nondominant shoulder in humeral head retroversion, glenoid retroversion, external rotation at 90°, and external rotation in the scapular plane. Internal rotation was decreased in the dominant shoulder. Total range of motion, anterior glenohumeral laxity, and posterior glenohumeral laxity were found to be equal bilaterally. The nonthrowing group demonstrated no significant difference in humeral head retroversion, glenoid retroversion, external rotation at 90° or external rotation in the scapular plane between shoulders, and no difference in internal rotation at 90°, total motion, or laxity. A comparison of the dominant shoulders of the two groups indicated that both external rotation at 90° and humeral head retroversion were significantly greater in the throwing group.

DOI： 10.1177/03635465020300011701

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Between 1996 and 1999, we evaluated 286 patients with chronic heel pain. We identified 14 patients who were diagnosed and surgically treated for a unique combination of plantar fasciitis, posterior tibial tendon dysfunction and tarsal tunnel syndrome. We postulate that failure of the static (plantar fascia) and dynamic (posterior tibial tendon) support of the longitudinal arch of the foot has resulted in traction injury to the posterior tibial nerve, i.e., tarsal tunnel syndrome. The combination of plantar fasciitis, posterior tibial tendon dysfunction and tarsal tunnel syndrome was recognized and treated. We have called this combination the “Heel Pain Triad (HPT).” Using the AOFAS hindfoot rating system, retrospective chart review and patient examination revealed marked improvement in 85.7% of patients. Follow-up was done four to 33 months (mean follow-up was 17.1 months). Marked improvement was noted in the categories of pain, activity level, walking distance, walking surface and limp. Improvement was statistically significant for all categories.

DOI： 10.1177/107110070202300305

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: Previous studies among young pitchers have focused on the frequency and description of elbow injuries. The purpose of this study was to evaluate the frequency of elbow and shoulder complaints in young pitchers and to identify the associations between pitch types, pitch volume, and other risk factors for these conditions. Methods: A prospective cohort study of 298 youth pitchers was conducted over two seasons. Each participant was contacted via telephone after each game pitched to identify arm complaints. Generalized estimating equations were used to assess associations between arm complaints and independent variables. Results: The frequency of elbow pain was 26%; that of shoulder pain, 32%. Risk factors for elbow pain were increased age, increased weight, decreased height, lifting weights during the season, playing baseball outside the league, decreased self-satisfaction, arm fatigue during the game pitched, and throwing fewer than 300 or more than 600 pitches during the season. Risk factors for shoulder pain included decreased satisfaction, arm fatigue during the game pitched, throwing more than 75 pitches in a game, and throwing fewer than 300 pitches during the season. Conclusion: Arm complaints are common, with nearly half of the subjects reporting pain. The factors associated with elbow and shoulder pain were different, suggesting differing etiologies. Developmental factors may be important in both. To lower the risk of pain at both locations, young pitchers probably should not throw more than 75 pitches in a game. Other recommendations are to remove pitchers from a game if they demonstrate arm fatigue and limit pitching in nonleague games.

DOI： 10.1097/00005768-200111000-00002

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Generating consistent maximum ball velocity is an important factor for a baseball pitcher's success. While previous investigations have focused on the role of the upper and lower extremities, little attention has been given to the trunk, In this study it was hypothesized that variations in pelvis and upper torso kinematics within individual pitchers would be significantly associated with variations in pitched ball velocity. Nineteen elite baseball pitchers were analyzed using 3-D high-speed motion analysis. For inclusion in this study, each pitcher demonstrated a variation in ball velocity of at least 1.8 m/s (range: 1.8-3.5 m/s) during his 10 fastball pitch trials. A mixed-model analysis was used to determine the relationship between 12 pelvis and upper torso kinematic variables and pitched ball velocity. Results indicated that five variables were associated with variations in ball velocity within individual pitchers: pelvis orientation at maximum external rotation of the throwing shoulder (p = .026), pelvis orientation at ball release (p = .044), upper torso orientation at maximum external rotation of the throwing shoulder (p = .007), average pelvis velocity during arm cocking (p = .024), and average upper torso velocity during arm acceleration (p = .035). As ball velocity increased, pitchers showed an increase in pelvis orientation and upper torso orientation at the instant of maximal external rotation of the throwing shoulder. In addition, average pelvis velocity during arm cocking and average upper torso velocity during arm acceleration increased as ball velocity increased. From a practical perspective, the athlete should be coached to strive for proper trunk rotation during arm cocking as well as strength and flexibility in order to generate angular velocity within the trunk for maximum ball velocity.

DOI： 10.1123/jab.17.2.164

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: There have been no studies of the prevalence, characteristics, and factors associated with the history of prior farm injury among active farmers. No studies have had adequate numbers of black farmers to evaluate farm owner/farm worker and black/white similarities and differences. Methods: Our sample is based upon surveys administered to 1,310 active male farmers in nine rural counties in Alabama (5) and Mississippi (4). The farmers are white owner/operators (53.6%), black owner/operators (26.6%), and black workers (19.8%). Results: Overall, 23.4% of the farmers had a prior injury. Prior injury was more frequent among white owner/operators (29.1%), compared with black workers (18.9%), and black owner/operators (15.2%). In multiple logistic regression analyses, post-high school education and tiredness when farming were independently associated with prior injury in black owner/operators. In white owner/operators, age ≥60 years, post-high school education, full-time farming, tractor use, more pieces of machinery, hurry when farming, and alcohol consumption were associated with prior injury. In black workers, only being very careful was associated with prior injury. Conclusions: The results suggest that prevention efforts focusing on alcohol consumption, fatigue, and hurry when farming might reduce injuries; however, only a follow-up study of this sample can determine whether these associations reflect causal factors, recall, or selection bias.

DOI： 10.1002/(SICI)1097-0274(199905)35:5<499::AID-AJIM7>3.0.CO;2-6

開催年月日： 2020年12月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Kobe   国名：日本国  

Introduction: We recently created and validated the JKOOS+, a more culturally relevant knee outcomes survey for Japanese patients. This survey was developed using patients with knee osteoarthritis grades 1 to 4. However, we were unable to validate the responsiveness of the JKOOS+ to treatment due to the nature of that prior study. In this study we aimed to determine the responsiveness of the JKOOS+ to total knee arthroplasty (TKA). Methods: We prospectively enrolled 87 patients scheduled for TKA across 7 centers in Japan. We administered the JKOOS+ and the Oxford Knee Score (OKS) to patients preoperatively and at 1 year post-operatively. We then calculated the Pearson’s correlation coefficients between the novel J-Activities of Daily Living (JADL) and Knee Flexion (KF) domains and the OKS both pre- and post-operatively. Further, we calculated the standardized response mean (SRM) as a measure of responsiveness of the domains to TKA, a known effective surgical intervention. Results: We had no loss to follow-up. The cohort was 81% female with an average age of 74 years. On average, patients improved 18-35 points per JKOOS+ domain with the largest improvement seen in the Quality of Life Domain. Both the JADL and KF demonstrated strong correlations with the OKS (0.699-0.849). The JADL had the highest responsiveness of all JKOOS+ domains (SRM=1.61), which was identical to that of the OKS. The JADL had superior responsiveness to the JKOOS ADL (SRM=1.49). The KF was also responsive (SRM=1.11), equivalent to the responsiveness of the Pain and Symptoms domains. Conclusions: The modified JADL and new KF domains were successfully validated in the TKA population. Both JADL and KF domains demonstrated responsiveness after TKA. The JADL again demonstrated superior properties to the original JKOOS-ADL, presumably because of its improved cultural relevant for Japanese patients.

開催年月日： 2020年10月

記述言語：英語   会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：Phoenix   国名：アメリカ合衆国  

開催年月日： 2020年10月

記述言語：英語   会議種別：公開講演，セミナー，チュートリアル，講習，講義等  

開催地：Vancouver   国名：カナダ  

開催年月日： 2020年10月

記述言語：英語   会議種別：公開講演，セミナー，チュートリアル，講習，講義等  

開催地：Vancouver   国名：カナダ  

開催年月日： 2020年2月 - 2020年3月

記述言語：英語   会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：St. Petersburg   国名：アメリカ合衆国  

開催年月日： 2019年5月

記述言語：英語   会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：Cancun   国名：メキシコ合衆国  

開催年月日： 2019年5月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Cancun   国名：メキシコ合衆国  

開催年月日： 2019年5月

記述言語：英語   会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：Cancun   国名：メキシコ合衆国  

記述言語：英語  

DOI： 10.3928/01477447-20180109-02

記述言語：英語  

Total knee arthroplasty is a large contributor toMedicare costs. In an effort to lower costs and improve outcomes, the Centers for Medicaid and Medicare Services has implemented theComprehensiveCare for Joint Replacementmodel,which incentivizes surgeons to submit both general health and joint-specific patient-reported outcome measures (PROMs). However, in addition to using PROMs for reporting purposes, surgeons should also consider incorporating PROMs into clinical practice. Currently, PROMs are not widely implemented in the clinical setting despite their value in measuring factors such as patients expectations and mental state, which impact outcomes. Furthermore, as technology improves, PROM collection will become faster and more efficient. The information collected by PROMs can informtreatment decisions and facilitate communication between the surgeon and the patient.

DOI： 10.5435/JAAOS-D-16-00637

記述言語：英語  

DOI： 10.1016/j.arthro.2016.05.030

記述言語：英語  

The Center for Medicaid and Medicare Services has recently announced the inclusion of several patient-reported outcome measures (PROMs), including the abbreviated Hip Disability and Osteoarthritis Outcome Score and Knee Injury and Osteoarthritis Outcome Score for joint replacement (HOOS, JR and KOOS, JR) for the purpose of quality assessment in total hip and total knee replacement (THR and TKR). Historically, Center for Medicaid and Medicare Services and other agencies have used measures of process (eg, % vaccinated) or adverse events (eg, infection rates, readmission rates) for quality assessment. However, the use of PROMs has become a priority based on stated goals by the National Quality Strategy and Institute of Medicine for a more patient-centered approach. Here, we review several general health and joint-specific PROMs, which have been extensively used in research to assess treatment efficacy and discuss their relevance to the new criteria for quality assessment, particularly for THR and TKR. Although we expect HOOS, JR and KOOS, JR to yield much useful information in the near term, these surveys are likely an interim solution. In the future, we anticipate that novel measurement platforms, such as wearable technologies or patient-specific surveys, may open new and exciting avenues of research to discover which types of data-perhaps not previously available-best represent patient quality of life and satisfaction after THR, TKR, or other orthopedic procedures.

DOI： 10.1016/j.arth.2016.01.073

記述言語：英語  

— The International Society of Arthroplasty Registries (ISAR) Patient-Reported Outcome Measures (PROMs) Working Group have evaluated and recommended best practices in the selection, administration, and interpretation of PROMs for hip and knee arthroplasty registries. The 2 generic PROMs in common use are the Short Form health surveys (SF-36 or SF-12) and EuroQol 5-dimension (EQ-5D). The Working Group recommends that registries should choose specific PROMs that have been appropriately developed with good measurement properties for arthroplasty patients. The Working Group recommend the use of a 1-item pain question (“During the past 4 weeks, how would you describe the pain you usually have in your [right/left] [hip/knee]?”; response: none, very mild, mild, moderate, or severe) and a single-item satisfaction outcome (“How satisfied are you with your [right/left] [hip/knee] replacement?”; response: very unsatisfied, dissatisfied, neutral, satisfied, or very satisfied). Survey logistics include patient instructions, paper- and electronic-based data collection, reminders for follow-up, centralized as opposed to hospital-based follow-up, sample size, patient- or joint-specific evaluation, collection intervals, frequency of response, missing values, and factors in establishing a PROMs registry program. The Working Group recommends including age, sex, diagnosis at joint, general health status preoperatively, and joint pain and function score in case-mix adjustment models. Interpretation and statistical analysis should consider the absolute level of pain, function, and general health status as well as improvement, missing data, approaches to analysis and case-mix adjustment, minimal clinically important difference, and minimal detectable change. The Working Group recommends data collection immediately before and 1 year after surgery, a threshold of 60% for acceptable frequency of response, documentation of non-responders, and documentation of incomplete or missing data.

DOI： 10.1080/17453674.2016.1181816

記述言語：英語  

The International Society of Arthroplasty Registries (ISAR) Steering Committee established the Patient-Reported Outcome Measures (PROMs) Working Group to convene, evaluate, and advise on best practices in the selection, administration, and interpretation of PROMs and to support the adoption and use of PROMs for hip and knee arthroplasty in registries worldwide. The 2 main types of PROMs include generic (general health) PROMs, which provide a measure of general health for any health state, and specific PROMs, which focus on specific symptoms, diseases, organs, body regions, or body functions. The establishment of a PROM instrument requires the fulfillment of methodological standards and rigorous testing to ensure that it is valid, reliable, responsive, and acceptable to the intended population. A survey of the 41 ISAR member registries showed that 8 registries administered a PROMs program that covered all elective hip or knee arthroplasty patients and 6 registries collected PROMs for sample populations; 1 other registry had planned but had not started collection of PROMs. The most common generic instruments used were the EuroQol 5 dimension health outcome survey (EQ-5D) and the Short Form 12 health survey (SF-12) or the similar Veterans RAND 12-item health survey (VR-12). The most common specific PROMs were the Hip disability and Osteoarthritis Outcome Score (HOOS), the Knee injury and Osteoarthritis Outcome Score (KOOS), the Oxford Hip Score (OHS), the Oxford Knee Score (OKS), the Western Ontario and McMaster Universities Arthritis Index (WOMAC), and the University of California at Los Angeles Activity Score (UCLA).

DOI： 10.1080/17453674.2016.1181815

記述言語：英語  

Articular cartilage defects strongly predispose patients to developing early joint degeneration and osteoarthritis, but for more than 15 years, no new cartilage-repair technologies that we know of have been approved by the U.S. Food and Drug Administration. Many studies examining novel approaches to cartilage repair, including cell, tissue, or matrix-based techniques, have shown great promise, but completing randomized controlled trials (RCTs) to establish safety and efficacy has been challenging, providing a major barrier to bringing these innovations into clinical use. In this article, we review reasons that surgical innovations are not well-suited for testing through RCTs. We also discuss how analytical methods for reducing bias, such as propensity scoring, make prospective observational studies a potentially viable alternative for testing the safety and efficacy of cartilage-repair and other novel therapies, offering the real possibility of therapeutic innovation.

DOI： 10.2106/JBJS.15.00573

記述言語：英語  

DOI： 10.1007/s11999-015-4548-7

記述言語：英語  

DOI： 10.1007/s11999-015-4149-5

記述言語：英語  

Treatment outcome researchers in orthopaedics frequently report only tests of statistical significance between group means to evaluate the effectiveness of a given intervention. Although important in establishing that mean differences are not caused by chance, these methods do not reflect the extent to which an intervention produces improvements that are meaningful and represent a return to health. This is an issue that is often of great interest to patients and clinicians. Other methods use a percentage change in an outcome measure (eg, 25% reduction in pain score) to classify treatment responders but often do not indicate whether the treatment restored a patient to normal. Researchers have developed several indices that provide a metric for statistically defining the amount of change that patients consider to be important. In this article, we focus on the concept of "clinical significance" and the different methods that have been developed to define clinically significant change using statistics. We then present a hybrid method that can classify whether a patient has returned to normal function. We apply this method to real patient data to illustrate its use with different outcome instruments commonly used in orthopaedic sports medicine. We advocate that the addition of these methods to reports from clinical outcome studies can deepen our understanding of the impact of interventions on patients' lives.

DOI： 10.1177/0363546512457346

記述言語：英語  

DOI： 10.1016/S0749-8063(11)00431-2

記述言語：英語  

DOI： 10.1016/j.arthro.2011.02.001

記述言語：英語  

DOI： 10.1136/bmj.c160

記述言語：英語  

DOI： 10.1001/archinternmed.2009.144

記述言語：英語  

DOI： 10.1007/s11999-008-0325-1

記述言語：英語  

The coronal plane high tibial osteotomy is a novel technique that is used to treat tibiofemoral malalignment. The authors hypothesize that the coronal plane high tibial osteotomy is (1) efficacious in treating both varus and valgus tibiofemoral malalignment; (2) does not alter the slope of the proximal tibia; and (3) does not alter the relationship between the patella and tibial tubercle. A retrospective review of 25 patients with tibiofemoral malalignment (19 varus/6 valgus) treated with a coronal plane osteotomy with a minimum of 2-year follow-up was performed. A Kaplan-Meyer survival curve was performed using knee arthroplasty and a Hospital for Special Surgery (HSS) knee score <70 as failure criteria. The Insall-Salvati ratio and the proximal tibial slope were measured. A p value of 0.05 was considered significant. At 60-month follow-up, knees with initial varus malalignment had an 84% survival rate using both knee arthroplasty and the HSS score as endpoints. Knees with initial valgus malalignment had an 84 and 60% survival rate using knee arthroplasty and the HSS score as endpoints, respectively. There was no statistically significant change in the Insall-Salvati ratio and proximal tibial slope after coronal plane osteotomy. The coronal plane osteotomy is efficacious in treating varus and valgus tibiofemoral malalignment and does not alter the patellar-tibial tubercle relationship or the posterior tibial slope [case series (level of evidence: IV)].

DOI： 10.1007/s11420-007-9050-7

記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

DOI： 10.2106/00004623-200710001-00013

記述言語：英語  

It is clear that small area variation exists in orthopedics, but there is still much to learn. Given the many unanswered questions regarding area variation, regulatory policy at this time would be premature. The biggest piece of the puzzle that needs to be solved is the influence of disease prevalence and severity. While it seems unlikely this will explain all of the variation, it is equally unlikely that musculoskeletal diseases are distributed evenly across geopolitical boundaries, hence, it likely accounts for some of the observed variation. More patient-level studies need to be conducted in non-Medicare populations. For example, the extent to which area variation exists in sports medicine and knee surgery for younger patients is unknown. Profiling is likely here to stay. In accord, it should be exploited by the orthopedic community for its strengths while keeping in mind its limitations. Orthopedic surgeons should be at the forefront of this research and consequently influential in its evolution rather than have the managed care industry or government dictate policy.

記述言語：英語  

Research aims to reach valid conclusions through scientific enquiry. Valid conclusions can only be reached if bias is minimized or eliminated. Bias can potentially take place in the design, implementation, or analysis of a study. Various study designs reduce bias, and this article reviews some of the more common study designs in orthopaedic sports medicine. We also discuss bias and confounding factors as they relate to these studies.

DOI： 10.1016/S0749-8063(03)00705-9

記述言語：英語  

記述言語：英語  

種別：大会・シンポジウム等 

参加者数：3,500

種別：査読等 

外国語雑誌　査読論文数：117

日本語雑誌　査読論文数：0

国際会議録　査読論文数：50

国内会議録　査読論文数：0

種別：大会・シンポジウム等 

参加者数：3,500

種別：査読等 

外国語雑誌　査読論文数：86

日本語雑誌　査読論文数：0

国際会議録　査読論文数：40

国内会議録　査読論文数：0

種別：大会・シンポジウム等 

参加者数：1,000

種別：学会・研究会等 

種別：大会・シンポジウム等 

参加者数：3,500

種別：大会・シンポジウム等 

参加者数：3,000

種別：学会・研究会等 

種別：査読等 

外国語雑誌　査読論文数：12

国際会議録　査読論文数：50

種別：学会・研究会等 

種別：学会・研究会等 

種別：学会・研究会等