Sports Medicine Research

At Stanford, we understand that athletics are a vital part of life for adolescents. The development of physical motor skills, and the teamwork and communication tools acquired through sports and physical activity are important for well rounded adolescent growth and development. Through expert patient care- from your child’s clinical visits and surgical experience, to the physical therapy and return to play preparation- our goal is to provide your child with the best tools for a successful and timely return to their athletic endeavors. Our pediatric sports research team studies the best surgical treatments, care pathways, and rehabilitation programs to get your child back to 100% in the most efficient way possible.

Kevin Shea
Vice Chief of Pediatric Orthopaedic Surgery for Research, Stanford University (2018 - Present) Director of Pediatric Sports Medicine, Stanford University (2018 - Present) Assistant Surgeon-in-Chief for Quality and Supply Chain Management, LPCH, Stanford Children's Hospital (2018 - Present)

Publications

  • Distal Radius Interventions for Fracture Treatment (DRIFT) trial: study protocol for a multicentre randomised clinical trial of completely translated distal radius fractures at paediatric hospitals in North America. BMJ open Balmert Bonner, L., Janicki, J., Georgiadis, A., Truong, W., Harris Beauvais, D., Belthur, M., Daley, E. L., Franzone, J., Howard, A., May, C., Rockhold, F., Schulz, J., Bailey, M., Chiswell, K., DeLaRosa, J., Brooks, J. T., Cantanzano, A. A., Chan, A., Chu, A., Dodwell, E. R., El-Hawary, R., Ellis, H., Fitzgerald, R., Frick, S., Ganley, T. J., Gargiulo, D., Gauthier, L., Gill, C. S., Goldstein, R., Halsey, M. F., Hardesty, C., Ho, C., Kaushal, N., Lawrence, J. T., Lee, R. J., Leitch, K. K., Masrouha, K., Mitchell, S., OMalley, N., Payares-Lizano, M., Perry, D., Ramalingam, W., Rhodes, J., Sanders, J., Shah, A. S., Sharkey, M., Silva, M., Silva, S., Thompson, R., Vorhies, J., Wright, J. G., Young, C., Burgess, J., IMPACCT Consortium, Castaneda, P. G., Cruz, A. I., Shea, K., Thompson, R. 2025; 15 (10): e088273

    Abstract

    INTRODUCTION: Distal radius fractures are the most common fractures seen in the emergency department in children in the USA. However, no established or standardised guidelines exist for the optimal management of completely displaced fractures in younger children. The proposed multicentre randomised trial will compare functional outcomes between children treated with fracture reduction under sedation versus children treated with simple immobilisation.METHODS AND ANALYSIS: Participants aged 4-10 years presenting to the emergency department with 100% dorsally translated metaphyseal fractures of the radius less than 5cm from the distal radial physis will be recruited for the study. Those patients with open fractures, other ipsilateral arm fractures (excluding ulna), pathologic fractures, bone diseases, or neuromuscular or metabolic conditions will be excluded. Participants who agree to enrol in the trial will be randomly assigned via a minimal sufficient balance algorithm to either sedated reduction or in situ immobilisation. A sample size of 167 participants per arm will provide at least 90% power to detect a difference in the primary outcome of Patient-Reported Outcomes Measurement Information System Upper Extremity computer adaptive test scores of 4 points at 1 year from treatment. Primary analyses will employ a linear mixed model to estimate the treatment effect at 1 year. Secondary outcomes include additional measures of perceived pain, complications, radiographic angulation, satisfaction and additional procedures (revisions, refractures, reductions and reoperations).ETHICS AND DISSEMINATION: Ethical approval was obtained from the following local Institutional Review Boards: Advarra, serving as the single Institutional Review Board, approved the study (Pro00062090) in April 2022. The Hospital for Sick Children (Toronto, ON, Canada) did not rely on Advarra and received separate approval from their local Research Ethics Board (REB; REB number: 1000079992) on 19 July 2023. Results will be disseminated through publication in peer-reviewed journals and presentations at international conference meetings.TRIAL REGISTRATION NUMBER: NCT05131685.

    View details for DOI 10.1136/bmjopen-2024-088273

    View details for PubMedID 41161832

  • Immune Rejection of Orthopedic Tissue Allograft Scoping Review: Are we missing a cause of graft/procedural failure?: current concepts. Journal of ISAKOS : joint disorders & orthopaedic sports medicine Hofmann, G. H., Sarsour, R., Deursen, W. v., Alayleh, A., Duru, N., Whitaker, E., Shea, K. 2025: 101002

    Abstract

    Allograft transplants are commonly used in orthopedics. Unlike other transplanted tissues, orthopaedic tissue allografts are not HLA-matched. The clinical impact of immune response to allografts is poorly understood. Recent experience with allograft failures and reactions to ACL, MPFL, osteochondral, and meniscus transplants raises concern. This scoping review examines the literature on immunologic rejection of orthopedic tissue allograft using PubMed, Embase, Web of Science, and Scopus for studies describing immune rejection of orthopedic tissue allografts in humans and animals. Four reviewers independently screened titles/abstracts based on these criteria. Full texts were screened independently by two reviewers for inclusion. Variables of interest included the species, graft type, and graft treatment. Our literature search yielded 1625 articles, with 78 meeting the inclusion criteria. Of these studies, 30 (38.5%) were in humans, 16 (20.5%) in rats, and 11 (14.1%) in dogs. The remaining 21 studies were in a combination of rabbit, primate, mice, sheep, and cat subjects. The orthopedic tissues in these studies included 23 osteochondral (29.5%), 16 bone (20.5%), 13 cartilage (16.7%), 6 bone-tendon-bone (7.7%), and 12 tendon/ligaments (15.4%) with 8 (10.2%) of the studies specifically in menisci. Methods used to reduce immune response include freezing, irrigation, and immunosuppressant administration. Recorded histological evidence of immune response included cell apoptosis, type II collagen increase, IL secretion, and increased lymphocytes/plasma cells in the synovial fluid. The pathways proposed were mismatched in cell surface proteins as many studies conducted MHC class I matching, which reduced the immune response. Despite histological evidence, including HLA sensitization after transplant signaling an immune response, clinical significance was not observed. Recent clinical experience of increased MRI signal response to orthopedic allografts, along with patient symptoms, has raised questions about rejection. Clinical rejection reports are limited in this review. This immune response to orthopedic allografts must be considered and additional studies are needed to explore the relationship between rejection and clinical outcomes. This scoping review informs that there is a range of human and animal studies demonstrating various immunologic response presentations and severities with different orthopedic tissue allografts.

    View details for DOI 10.1016/j.jisako.2025.101002

    View details for PubMedID 40998173

  • The Anatomic Relationship of Medial Femoral Condyle Osteochondritis Dissecans to the Posterior Cruciate Ligament. Journal of pediatric orthopedics Milewski, M. D., Russ, S. D., Cannamela, P. C., Shea, K. G., Tompkins, M. A. 2025

    Abstract

    The purpose of this study was to define the anatomic relationship between the femoral origin of the posterior cruciate ligament (PCL) and medial femoral condyle (MFC) osteochondritis dissecans (OCD) lesions.Ninety-four magnetic resonance imaging (MRI) studies of a series of patients with MFC OCDs seen at a single institution from 2004 to 2014 were reviewed. The distances from the center of the PCL to the center of the OCD as well as the shortest distance from the PCL to the OCD were calculated in both the sagittal and coronal planes. The orientation of the OCD relative to the PCL was noted.The median distance between the center of the PCL origin and the center of the OCD was 14  mm in the coronal plane and 11 mm in the sagittal plane. The median distance from any point on the OCD to any point on the PCL origin was 3 mm in both planes. The OCD was within 1 cm of the PCL in all but 2 patients. 46.8% of OCD lesions were located posterior to the PCL origin in the sagittal plane.The classic medial femoral condyle OCD lesion is consistently in close proximity to the femoral origin of the PCL, and most lesions are medial and posterior to the PCL.Level III.

    View details for DOI 10.1097/BPO.0000000000003027

    View details for PubMedID 40799065

  • Age, Sex, and BMI Differences Related to Repairable Meniscal Tears in Pediatric and Adolescent Patients. The American journal of sports medicine Rohde, M. S., Shea, K. G., Dawson, T., Heyworth, B. E., Milewski, M. D., Edmonds, E. W., Adsit, E., Wilson, P. L., Albright, J., Algan, S., Beck, J., Bowen, R., Brey, J., Cardelia, M., Clark, C., Crepeau, A., Edmonds, E. W., Ellington, M., Ellis, H. B., Fabricant, P., Frank, J., Ganley, T., Green, D., Gupta, A., Heyworth, B. E., Latz, K., Mansour, A., Mayer, S., McKay, S., Milewski, M., Niu, E., Pacicca, D., Parikh, S., Rhodes, J., Saper, M., Schmale, G., Schmitz, M., Shea, K., Storer, S., Wilson, P. L., Ellis, H. B. 2023: 3635465221145939

    Abstract

    The incidence of meniscus tears and ACL tears in pediatric patients continues to rise, bringing to question the risk factors associated with these injuries. As meniscus tears are commonly repaired in pediatric populations, the epidemiology of repairable meniscus tears is an important for consideration for surgeons evaluating treatment options.To describe meniscal tear patterns in pediatric and adolescent patients who underwent meniscal repair across multiple institutions and surgeons, as well as to evaluate the relationship between age, sex, and body mass index (BMI) and their effect on the prevalence, type, and displacement of repaired pediatric meniscal tears.Case series; Level of evidence, 4.Data within a prospective multicenter cohort registry for quality improvement, Sport Cohort Outcome Registry (SCORE), were reviewed to describe repaired meniscal tear patterns. All consecutive arthroscopic meniscal repairs from participating surgeons in patients aged <19 years were analyzed. Tear pattern, location, and displacement were evaluated by patient age, sex, and BMI. A subanalysis was also performed to investigate whether meniscal tear patterns differed between those occurring in isolation or those occurring with a concomitant anterior cruciate ligament (ACL) injury. Analysis of variance was used to generate a multivariate analysis of specified variables. Sex, age, and BMI results were compared across the cohort.There were 1185 total meniscal repairs evaluated in as many patients, which included 656 (55.4%) male and 529 (44.6%) female patients. Patients underwent surgery at a mean age of 15.3 years (range, 5-19 years), with a mean BMI of 24.9 (range, 12.3-46.42). Of the 1185 patients, 816 (68.9%) had ACL + meniscal repair and 369 (31.1%) had isolated meniscal repair. The male patients underwent more lateral tear repairs than the female patients (54.3% to 40.9%; P < .001) and had a lower incidence of medial tear repair (32.1% vs 41.4%; P < .001). Patients with repaired lateral tears had a mean age of 15.0 years, compared with a mean age of 15.4 years for patients with repaired medial or bilateral tears (P = .001). Higher BMI was associated with "complex" and "radial" tear repairs of the lateral meniscus (P < .001) but was variable with regard to medial tear repairs.In pediatric and adolescent populations, the data suggest that the surgical team treating knees with potential meniscal injury should be prepared to encounter more complex meniscal tears, commonly indicated in those with higher BMI, while higher rates of lateral meniscal tears were seen in male and younger patients. Future studies should analyze correlates for meniscal repair survival and outcomes in this pediatric cohort undergoing knee surgery.

    View details for DOI 10.1177/03635465221145939

    View details for PubMedID 36629442

  • Longitudinal 3T MRI T2 * Mapping of Juvenile Osteochondritis Dissecans (JOCD) Lesions Differentiates Operative from Non-operative Patients - Pilot Study. Journal of orthopaedic research : official publication of the Orthopaedic Research Society Kajabi, A. W., Zbyn, S., Johnson, C. P., Tompkins, M. A., Nelson, B. J., Takahashi, T., Shea, K. G., Marette, S., Carlson, C. S., Ellermann, J. M. 2022

    Abstract

    Juvenile osteochondritis dissecans (JOCD) is an orthopedic joint disorder of children and adolescents that can lead to premature osteoarthritis. Thirteen patients (mean age: 12.3 years, 4 females), 15 JOCD-affected and five contralateral healthy knees, that had a baseline and a follow-up MRI (mean interval of 8.9 months) and were treated non-operatively during this interval were included. Retrospectively, patients were assigned to operative or non-operative groups based on their electronic medical records. Volumetric mean T2 * values were calculated within regions of interest (progeny lesion, interface, parent bone) and region matched control bone in healthy contralateral knees and condyles. The normalized percentage difference of T2 * between baseline and follow up MRI in non-operative patients significantly increased in progeny lesion (-47.8%, p < 0.001), parent bone (-13.9%, p < 0.001), and interface (-32.3%, p = 0.011), whereas the differences in operative patients were non-significant and below 11%. In non-operative patients, the progeny lesion (p < 0.001) and interface T2 * values (p = 0.012) were significantly higher than control bone T2 * at baseline, but not at follow-up (p = 0.219, p=1.000, respectively). In operative patients, the progeny lesion and interface T2 * values remained significantly elevated compared to the control bone both at baseline (p < 0.001, p < 0.001) and follow-up (p < 0.001, p < 0.001), respectively. Clinical Significance: Longitudinal T2 * mapping differentiated non-healing from healing JOCD lesions following initial non-operative treatment, which may assist in prognosis and improve the ability of surgeons to make recommendations regarding operative versus non-operative treatment. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1002/jor.25343

    View details for PubMedID 35430743

  • Youth athletes sleep more, practice less, and may lose interest in playing sports due to social distancing mandates. Preventive medicine reports Ellis, H. B., Ulman, S. M., John Wagner, K., Carpenter, C. M., Gale, E. B., Shea, K. G., Wilson, P. L. 2022; 26: 101722

    Abstract

    In-person sport participation was suspended across the United States in the spring of 2020 to slow the spread of the novel coronavirus (COVID-19). The purpose of this study was to survey the impact of COVID-19 on young athletes during a period of social and organized sports restrictions. An anonymous cross-sectional survey study was conducted of youth athletes in the midst of social distancing mandates and consisted of six components: demographics, sport participation, changes in sport-related goals/aspirations, sleep habits, and measures of anxiety and depression. 711 individuals who accessed the survey link yielded 575 (81%) participants with responses available for analysis. All respondents (aged 13.0years) played organized sports, 62% were single-sport athletes, and 74% considered high-level. Participants were training 3.3h less per week, spending more time outside, and 86% of participants continued to train while social distancing. Sleep duration increased (1.2h/night) and sleep quality improved in 29% of young athletes. Additionally, 22% and 28% reported PROMIS anxiety and depression scores characterized as 'mild', 'moderate', or 'severe'. Older single-sport participants reported higher depression scores, while higher anxiety scores were seen in female participants with fewer years played. 10% of young athletes and 20% of teenagers changed their sports-related goals. Training style modifications, decreased training, and increased sleep quantity and quality were positive effects of COVID-19 restrictions, while athletic aspirational changes were undesirable effects. Single-sport athletes may be at greater risk for psychological symptoms when their routine is altered.

    View details for DOI 10.1016/j.pmedr.2022.101722

    View details for PubMedID 35132371

  • Increased Vascularity in the Neonatal versus Adult Meniscus: Evaluation with Magnetic Resonance Imaging. Cartilage Lin, K. M., Gadinsky, N. E., Klinger, C. E., Dyke, J. P., Rodeo, S. A., Green, D. W., Fabricant, P. D., Helfet, D. L., Shea, K. G., Lazaro, L. E. 2020: 1947603520923143

    Abstract

    Objective. Quantification of meniscus vascularity has been limited with previous techniques, and minimal data exist describing differential vascular zones in the skeletally immature meniscus. The objective of this study is to use quantitative contrast-enhanced magnetic resonance imaging (MRI) to compare meniscal vascularity in neonatal specimens with adults. We hypothesized that the developing meniscus has greater and more uniform vascularity throughout all zones. Design. Ten fresh-frozen human cadaveric knees (5 neonatal, age 0-6 months; 5 adult, 34-67 years) underwent gadolinium-enhanced MRI using an established vascularity quantification protocol. Regions of interest corresponding to peripheral and central zones of the meniscus were identified on pre-contrast coronal images, and signal enhancement within the same regions (normalized against background tissue) was compared between pre- and post-contrast images. Results. The medial and lateral menisci had similar distribution of perfusion (45.8% ± 8.1% medial vs. 54.2% ± 8.1% lateral in neonatal knees; 50.6% ± 11.3% medial vs. 49.4% ± 11.3% lateral in adult knees, P = 0.47). Increased perfusion was demonstrated in the periphery compared with the central zone (2.3:1 in neonatal knees and 3.25:1 in adult knees, P = 0.31). Neonatal specimens demonstrated 6.0-fold greater overall post-contrast meniscal signal enhancement compared with adults (P < 0.0001), with the 0-month specimen demonstrating the greatest proportional signal enhancement. Conclusions. While blood flow to the periphery is greater than to central zones in all menisci, younger menisci receive proportionally greater overall blood flow compared to adults, including to the central zone, suggesting that the immature meniscus is a more biologically active tissue than its adult counterpart.

    View details for DOI 10.1177/1947603520923143

    View details for PubMedID 32447965

For Complete list of Dr. Shea's Publications visit any of the links below 

Faculty Contact

Dr. Kevin Shea

Research Contact

Bryan Khoo

bkhoo@stanford.edu