Impact of Donor-Recipient Sex-Mismatch on Graft Failure in Osteochondral Allograft Procedures: A Systematic Review.

Background: While midterm outcomes of donor-recipient sex-mismatch have been reported after knee osteochondral allograft procedures, no studies have been conducted to report on all available literature. Purpose: To investigate whether sex-mismatch between donor and recipient influences graft survival in studies evaluating knee OCA surgery. Study Design: Systematic review; Level of evidence, 3. Methods: A systematic review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Three databases (PubMed, Embase, and Cochrane) were searched for published studies evaluating donor sex-specific outcomes in human subjects. Studies were included regardless of the level of evidence. All studies were manually screened, followed by a full-text review and data extraction. All outcome measures reported in studies were recorded. The extracted data were reported as descriptive statistics. A risk-of-bias assessment was also conducted for each identified study. Results: Of 140 full-text articles screened, 4 articles were included in this analysis. Of these, 1 study concluded that a donor-recipient sex mismatch is a negative predictor of outcomes, while 3 studies (75%) found no difference in postoperative outcomes between donor-recipient pairs. Two studies analyzed individual sex pairings (eg, female-to-male pairing), and 1 found lower survival in male-to-female grafts. A failure rate of 14% OCA was observed across 973 knees-including 514 male recipients (53%) and 459 female recipients (47%). At baseline, concomitant tibial tubercle osteotomy was more common in sex-mismatched pairing (14% compared with 8%), and concomitant high tibial osteotomy in sex-matched pairing (9% compared with 4%). Other adjuvant procedures and patient characteristics were comparable. Failure rate for donor-recipient sex-matched and sex-mismatched cohorts was 15% and 13%, respectively. Conclusion: This study assessed the current literature to determine the role of donor-recipient sex pairing in the outcomes of OCA transplantation. Only 1 study (25%) concluded a significant difference in graft failure among sex-matched and mismatched cohorts. A principal concern of this review is that only 4 studies report data on donor-recipient sex pairings. Only one-fifth of all patients received a female donor graft, limiting the ability to draw conclusions about subgroups. Graft failure across all studies was comparable between sex-matched and sex-mismatched cohorts. This study supports current graft-matching practices, primarily based on size and anatomy, without sex matching.