PURPOSE

To assess the current literature for differences in return-to-sport (RTS) rates between male and female athletes after common cartilage procedures in the knee including autologous chondrocyte implantation (ACI), matrix-induced autologous chondrocyte implantation (MACI), osteochondral autograft transplantation (OAT), and osteochondral allograft transplantation (OCA).

METHODS

Electronic databases were searched from inception to November 2024. Two independent reviewers screened 2,482 articles. The inclusion criteria were studies published between 2004 and 2024, with level of evidence I to IV, reporting RTS data and sex-specific outcomes after OAT, MACI, ACI, or OCA of the knee, with a minimum 12-month follow-up. The main outcome was the difference in RTS rates between male and female athletes. RTS was defined as the percentage of athletes able to resume sport or military duty, as well as the percentage able to return to their preinjury level or full duty. A meta-analysis was conducted using the inverse variance method with a random-effects model to account for both within- and between-study variability to identify sex differences in RTS rates. Statistical analyses were conducted using R (version 2024.09.0+375).

RESULTS

Twenty-two primary studies, encompassing 1,468 athletes who underwent OAT, MACI, ACI, or OCA, reported sex-specific outcomes. Fifteen of these reported no statistically significant differences in RTS rates between female and male athletes. Five studies reported better RTS rates in male athletes, and one reported a better RTS rate in female athletes. Only one study reported sex-specific differences in return to preinjury level. Meta-analysis identified RTS rates of 75% for male athletes and 56% for female athletes.

CONCLUSIONS

There is a paucity of available data on RTS based on sex after contemporary cartilage procedures for chondral injuries of the knee. Meta-analysis of available data suggests female athletes may have more difficulty with returning to sport than male athletes.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II and IV studies.