Return to Sport in Athletes After Osteochondral Allograft Transplantation: A Systematic Review

Background: Management of symptomatic osteochondral defects of the knee remains challenging because of the limited inherent vascularity and healing potential of articular cartilage. Osteochondral allograft (OCA) transplantation has yielded satisfactory results in appropriate patients; however, the effect of OCA transplantation on athletes seeking to return to sport (RTS) remains largely unknown. Purpose: To systematically review the literature to better understand outcomes after OCA, focusing on RTS rate and timing, and the incidence of postoperative complications. Study Design: Systematic review; Level of evidence, 4. Methods: Studies included in the PubMed, EMBASE, and Cochrane Library databases from inception to August 2024 that reported on athletes participating at the recreational, high school, collegiate, and professional levels undergoing OCA transplantation for osteochondral defects in the knee were identified. Inclusion criteria included studies reporting on patients identified as athletes undergoing OCA transplantation with reported origin, lesion characteristics (size and location), RTS rate and timing, complications, reoperations, and patient-reported outcomes. Results: A total of 14 studies, consisting of 471 athletes undergoing OCA transplantation with a weighted mean follow-up of 51.1 months, were identified. The weighted mean patient age was 31.4 years (range, 15-69 years), with 61% of patients being male. Lesion origin was reported in 49% (230/471) of patients, with osteochondritis dissecans (OCD) reported in 44% (100/230). The medial femoral condyle was the most common defect location (44%; 68/153). Lesion size ranged from 1 to 13.94 cm 2 . Sixteen percent (75/471) of patients were classified as competitive athletes, with basketball (n = 21) being the most common sport. RTS was reported in 72% (338/468) of patients, with 84% (231/275) returning at an equal or higher level of play at a weighted mean of 11.1 months (range, 6-26 months) after OCA. Complications were reported in 12% (41/351) of patients, with graft failure accounting for 54% (22/41) of complications in 6% (22/351) of patients. Conclusion: For athletes undergoing OCA transplantation to the knee, OCD was the most commonly reported cause, with the medial femoral condyle most frequently affected. Successful RTS was reported in 72% of patients at a mean of 11.1 months, with graft failure representing the most common complication in 6%.