High Variability in Return-to-Sport Assessment After Autologous Chondrocyte Implantation of the Knee: A Systematic Review

Purpose To systematically review return-to-sport (RTS) patient-reported outcome measure (PROM) usage following autologous chondrocyte implantation (ACI) and matrix-induced autologous chondrocyte implantation (MACI). We hypothesized that RTS reporting would be highly inconsistent, limiting clinical applicability. Methods A systematic review was conducted using PubMed, Embase, and Scopus (January 1, 2014–December 8, 2024). Eligible studies reported RTS PROMs after ACI/MACI. Extracted data included study design, demographics, name and type of scale used, and assessment modality. Results Of 807 studies screened, 85 met inclusion criteria. Measures used to report RTS varied widely. The Knee injury and Osteoarthritis Outcome Score–Sport/Rec and the International Knee Documentation Committee Subjective Knee Evaluation Form were the most commonly reported validated PROMs, included in 71.8% and 49.4% of studies, respectively. Only 15.3% of studies reported RTS as a postoperative percentage. Of all, 22.4% of studies used custom, nonvalidated tools. Most studies (49.4%) were prospective, and in-person evaluation was most common (52.8%). Timepoints of RTS measurement were inconsistent. Conclusions RTS is inconsistently quantified following ACI/MACI, limiting cross-study comparisons and complicating clinical interpretation of outcomes. Standardized use of and expansion of validated PROMs is needed to improve the clinical applicability of data on RTS for ACI/MACI