Summary

This study found no observable differences in short-term clinical outcomes, patient satisfaction, or complications/reoperation rates based on sex of the graft donor in patients undergoing osteochondral allograft transplantation

Abstract

Purpose

Donor or graft-related characteristics have been increasingly examined in patients receiving osteochondral allograft (OCA) procedures to identify potential contributors for adverse outcomes. While favorable outcomes have been reported for patients undergoing OCA transplantation, there are still reports of return to sport ranging from 60-80% and reoperation rates up to 30-40%. Prior reports have suggested increased risk of graft failure long term in patients with graft donor-recipient sex mismatch. Therefore, the purpose of this study was to evaluate the potential effect of donor-recipient sex mismatch in OCA transplantation with respect to clinical outcomes, satisfaction, and return to sport (RTS).

Methods

This retrospective study identified patients who underwent osteochondral allograft (OCA) transplantation of the knee at a single institution with a minimum of 1 year of clinical follow-up. Patient-reported outcomes were measured using the Visual Analog Scale (VAS) for pain and satisfaction and the Knee Injury and Osteoarthritis Outcome Score (KOOS). RTS and complications were analyzed. Complications included, infection, need for readmission, deep vein thrombosis/pulmonary embolism, need for reoperation, and graft failure. Patients were divided into two cohorts (same-sex donor (SS) and different-sex donor (DS)) and outcomes were compared between these two groups using T-tests and chi-square analyses. ANCOVA and logistic regression models were used to control for confounders. Subsequent sub-analyses were performed to identify differences between the four donor-recipient groups (male-male, female-male, male-female, and female-female) using ANOVA and Chi-square analyses.

Results

A total of 80 patients were included (50 in same-sex donor group and 30 in the different-sex donor group) with a mean follow-up of 41.1± 22.5 months. There was a difference in age between the groups (37.9 ± 12.0 years in the same-sex group vs. 30.5 ± 9.4 years in the different-sex group, p=0.005), but no difference in BMI. No differences were observed between the SS and DS groups with respect to satisfaction, pain, and KOOS outcome scores with the mean satisfaction of the SS donor group being 72.8 ± 27.9 and 80.2 ± 29.9 for the DS donor group. After controlling for age, the differences remained not significant. 63.3% of same-sex donor patients returned to sport compared to 53.6% (p=0.404). The overall complication and reoperation rates were 26.3% and 25.0%, with no difference between the DS and SS groups. There were two graft failures noted, both of which were in the same-sex donor group (male donor-male patient) with no difference. The majority of patients in the SS donor group were male-male (n=37) and the majority of patients in the DS donor group were male donors for female patients (n=25). When dividing into the respective donor-recipient groups, there was also no difference between the groups with respect to clinical outcomes, satisfaction, and rate of RTS.

Conclusion

There were no observable differences in short-term clinical outcomes, patient satisfaction, or complications/reoperation rates based on sex of the graft donor in patients undergoing OCA transplantation. Further studies should be performed with longer term follow-up to determine the influence of donor sex on clinical outcomes in patients with OCA procedures in the knee.