九州大学 研究者情報
研究者情報 (研究者の方へ)入力に際してお困りですか?
基本情報 研究活動 教育活動 社会活動
LYMAN STEPHEN LEONARD(ライマン スティーブンレオナルド) データ更新日:2023.11.22



主な研究テーマ
I am involved primarily in research revolving around health policy and outcomes measurement in orthopedic surgery as it relates to the hip and knee joints.
キーワード:orthopedics, sports medicine, knee, hip, epidemiology, clinical outcomes
2018.10~2029.09.
研究業績
主要原著論文
1. Yokota N, Lyman S, Hanai H, Shimomura K, Ando W, Nakamura N., Clinical Safety and Effectiveness of Adipose-Derived Stromal Cell vs Stromal Vascular Fraction Injection for Treatment of Knee Osteoarthritis: 2-Year Results of Parallel Single-Arm Trials, American Journal of Sports Medicine, 10.1177/03635465221107364 Format:, 50, 10, 2659-2668, 2022.08, Background: There are currently no disease-modifying treatments available for knee osteoarthritis (OA), although cultured adipose-derived stromal cells (ASCs) have shown promise in experimental models. However, given the regulatory limits on the use of cultured cells in humans, previous trials have focused primarily on the stromal vascular fraction (SVF) intra-articular injection. Therefore, the therapeutic value of ASCs for knee OA remains unknown.

Purpose: To study ASC versus SVF intra-articular injection in patients with Kellgren-Lawrence (KL) knee OA grades 2 to 4 in parallel single-arm trials.

Study design: Cohort study; Level of evidence, 2.

Methods: A total of 80 patients were enrolled, with 42 (72 knees) receiving ASC intra-articular injection and 38 (69 knees) receiving SVF. Patient-reported outcome measures were assessed at 1, 3, 6, 12, and 24 months using the Knee injury and Osteoarthritis Outcome Score 5 (KOOS5) and pain visual analog scale (VAS). The percentages of patients achieving the minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) were also calculated. Per protocol, a subset of the ASC group received an ASC booster injection after 6 months. A repeated-measures analysis of variance compared results between treatment arms and by KL grade over time.

Results: Patient-reported outcome measures improved substantially after both treatments (P
Conclusion: This represents the first head-to-head comparison of ASCs and SVF for the treatment of knee OA in humans. ASC and SVF injections both substantially improved knee pain and function at all follow-up time points, although ASC injections demonstrated significantly better improvements with regard to the MCID and PASS for the pain VAS and the MCID for the KOOS5 at 12 months. There appears to be no benefit to a booster ASC injection after initial treatment. Given less donor-site morbidity and equivalent superior outcomes at 2 years, the use of ASCs over SVF in the treatment of knee OA may be warranted..
2. Ilan Fleisher; Madison Thompson; Curits Mensah; Joseph, Amethia D.; McLawhorn, Alexander S.; Padgett, Douglas E.; Lyman, Stephen, Development and Validation of Crosswalks Between the Western Ontario & McMaster Universities Osteoarthritis Index and Hip Disability and Osteoarthritis Outcome Score Joint Replacement/ Knee Injury and Osteoarthritis Outcome Score Joint Replacement, JOURNAL OF ARTHROPLASTY, 10.1016/j.arth.2021.11.009, 37, 6, 1034-+, 2022.06.
3. Kunze KN, Fontana MA, MacLean CH, Lyman S, McLawhorn AS., Defining the Patient Acceptable Symptom State for the HOOS JR and KOOS JR After Primary Total Joint Arthroplasty, Journal of Bone and Joint Surgery, doi: 10.2106/JBJS.21.00550., 104, 4, 345-352, 2022.02.
4. Boyle KK, Kapadia M, Chiu YF, Khilnani T, Miller AO, Henry MW, Lyman S, Carli AV., The James A. Rand Young Investigator's Award: Are Intraoperative Cultures Necessary If the Aspiration Culture Is Positive? A Concordance Study in Periprosthetic Joint Infection., Journal of Arthroplasty, 10.1016/j.arth.2021.01.073., 2021.07, Background: The concordance between preoperative synovial fluid culture and multiple intraoperative tissue cultures for identifying pathogenic microorganisms in periprosthetic joint infection (PJI) remains unknown. Our aim is to determine the diagnostic performance of synovial fluid culture for early organism identification.

Methods: A total of 363 patients who met Musculoskeletal Infection Society criteria for PJI following primary total joint arthroplasty were identified from a retrospective joint infection database. Inclusion criteria required a positive preoperative intra-articular synovial fluid sample within 90 days of intraoperative tissue culture(s) at revision surgery. Concordance was defined as matching organism(s) in aspirate and intraoperative specimens.

Results: Concordance was identified in 279 (76.8%) patients with similar rates among total hip arthroplasties (77.2%) and total knee arthroplasties (76.4%, P = .86). Culture discordance occurred in 84 (23.1%) patients; 37 (10.2%) had no intraoperative culture growth and 33 (90.1%) were polymicrobial. Monomicrobial Staphylococcal PJI cases had high sensitivity (0.96, 95% confidence interval [CI] 0.92-0.98) and specificity (0.85, 95% CI 0.80-0.90). Polymicrobial infections had the lowest sensitivity (0.06, 95% CI 0.01-0.19).

Conclusion: Aspiration culture has favorable sensitivity and specificity when compared to tissue culture for identifying the majority of PJI organisms. Clinicians can guide surgical treatment and postoperative antibiotics based on monomicrobial aspiration results, but they should strongly consider collecting multiple tissue cultures to maximize the chance of identifying an underlying polymicrobial PJI..
5. Polascik BA, Hidaka C, Thompson MC, Tong-Ngork S, Wagner JL, Plummer O, Lyman S., Crosswalks Between Knee and Hip Arthroplasty Short Forms: HOOS/KOOS JR and Oxford, Journal of Bone and Joint Surgery, 10.2106/JBJS.19.00916., 2020.06, 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..
6. Blevins JL, Rao V, Chiu YF, Lyman S, Westrich GH., Predicting implant size in total knee arthroplasty using demographic variables., Bone and Joint Journal, 10.1302/0301-620X.102B6.BJJ-2019-1620.R1., 2020.06, Aims: The purpose of this investigation was to determine the relationship between height, weight, and sex with implant size in total knee arthroplasty (TKA) using a multivariate linear regression model and a Bayesian model.

Methods: A retrospective review of an institutional registry was performed of primary TKAs performed between January 2005 and December 2016. Patient demographics including patient age, sex, height, weight, and body mass index (BMI) were obtained from registry and medical record review. In total, 8,100 primary TKAs were included. The mean age was 67.3 years (SD 9.5) with a mean BMI of 30.4 kg/m2 (SD 6.3). The TKAs were randomly split into a training cohort (n = 4,022) and a testing cohort (n = 4,078). A multivariate linear regression model was created on the training cohort and then applied to the testing cohort . A Bayesian model was created based on the frequencies of implant sizes in the training cohort. The model was then applied to the testing cohort to determine the accuracy of the model at 1%, 5%, and 10% tolerance of inaccuracy.

Results: Height had a relatively strong correlation with implant size (femoral component anteroposterior (AP) Pearson correlation coefficient (ρ) = 0.73, p
Conclusion: Implant size was correlated with basic demographic variables including height, weight, and sex. The linear regression and Bayesian models accurately predicted required implant sizes across multiple manufacturers based on height, weight, and sex alone. These types of predictive models may help improve operating room and implant supply chain efficiency..
主要総説, 論評, 解説, 書評, 報告書等
主要学会発表等
1. Stephen Lyman PhD, Norimasa Nakamura MD PhD, Masataka Deie MD PhD, Naoshi Fukui MD PhD, Harukazu Tohyama MD PhD, Hiroshi Ikeda MD PhD, Takahisa Sasho MD PhD, Go Omori MD PhD , JKOOS+ Validation of a Culturally Relevant Japanese Knee Survey , Japanese Orthopaedic Society of Knee, Arthroscopy and Sports Medicine (JOSKAS), 2019.06.
学会活動
所属学会名
International Society of Arthoprlasty Registeries
日本関節鏡・膝・スポーツ整形外科学会
International Society of Arthroscopy, Knee Surgery, and Orthopaedic Sports Medicine
学協会役員等への就任
2017.05~2024.04, JOSKAS, Member, JOSKAS Knee Research Committee.
2016.05~2020.05, International Society of Arthroplasty Registries, 運営委員.
2009.05~2022.05, International Society of Arthroscopy, Knee Surgery & Orthopaedic Sports Medicine, 運営委員.
2019.05~2023.05, International Society of Arthroscopy, Knee Surgery & Orthopaedic Sports Medicine, 運営委員.
2019.05~2023.05, International Society of Arthroscopy, Knee Surgery & Orthopaedic Sports Medicine, Past Chairman of ISAKOS Communications Committee.
学会大会・会議・シンポジウム等における役割
2023.06.18~2023.06.21, ISAKOS World Congress, invited speaker.
2021.11.27~2021.11.28, ISAKOS World Congress, Invited Speaker.
2020.12.17~2020.12.19, JOSKAS, Moderator, invited speaker.
2019.05.07~2019.05.10, ISAKOS, invited speaker.
2019.06.13~2019.06.17, JOSKAS, Moderator, invited speaker.
2019.10.05~2019.10.08, International Cartilage Repair Society (ICRS) World Congress, Moderator, invited speaker.
学会誌・雑誌・著書の編集への参加状況
2023.01~2025.12, Journal of Joint Surgery and Research, 国際, 編集委員.
2019.07~2023.12, Introduciton to Surgical Trials, 国際, 編集委員長.
2015.06~2024.06, Jouranl of Bone and Joint Surgery, 国際, 編集委員.
2019.05~2020.12, Journal of ISAKOS, 国際, 編集委員.
2015.06~2024.06, Journal of ISAKOS, 国際, 編集委員.
2013.06~2023.06, HSS Journal, 国際, 編集委員.
学術論文等の審査
年度 外国語雑誌査読論文数 日本語雑誌査読論文数 国際会議録査読論文数 国内会議録査読論文数 合計
2023年度 43        43 
2022年度 85  85 
2021年度 45  50  95 
2020年度 86  40  126 
2019年度 12    50    62 
その他の研究活動
海外渡航状況, 海外での教育研究歴
University of Rochester, UnitedStatesofAmerica, 2019.10~2019.10.

九大関連コンテンツ

pure2017年10月2日から、「九州大学研究者情報」を補完するデータベースとして、Elsevier社の「Pure」による研究業績の公開を開始しました。