Return to Sport in Professional Athletes After Cartilage Restoration Surgery of the Knee: A Systematic Review and Meta-Analysis Demonstrates Gender Inequality and the Need for Improved Reporting.

Abstract

To synthesize the literature concerning return to sport (RTS) and related outcomes after cartilage restoration surgery of the knee in professional athletes. Cochrane, PubMed, and OVID/Medline databases were queried for data pertaining to RTS after knee cartilage surgery in professional athletes. Demographic information, cartilage lesion characteristics, and RTS-specific information were extracted. Freeman-Tukey Double-Arscine Transformations with Dersimonian-Laerd random-effects estimators were constructed to quantitatively describe the cumulative incidence of RTS, while heterogeneous data described narratively. Eleven studies (476 athletes; mean age 27.5 ± 2.1 years; 96.6% male) were included. Nine (81.8%) studies investigated a form of microfracture as treatment, with 6 (54.5%) performing isolated microfracture. The remaining studies investigated osteochondral allograft transplantation and mosaicplasty. More than half (n = 6; 54.5%) did not report cartilage lesion location or size. The pooled RTS rate was 84.3% (95% CI: 75.4%-91.8%) at a mean 39.9 (range, 12-104) weeks postoperatively. In 6 studies reporting competition level, a trend toward returning to a lower than pre-injury level was observed. The definition of RTS was only provided in 6 (54.5%) studies, while the criteria for RTS was only reported in 2 (18.2%) studies, suggesting limited transparency. One study reported an objective imaging assessment of reparative tissue, while none reported formal RTS testing protocols or minimum RTS timeline. Although the majority of professional athletes are reported to achieve a successful RTS after cartilage restoration surgery of the knee, the literature predominantly reflects microfracture treatment. Current limitations in this literature include a substantial lack of female representation and infrequent reporting of cartilage lesion characteristics, rehabilitation and RTS criteria, and objective imaging assessments of reparative tissue.