Background: Physicians counseling athletes on the prognosis of sport-specific performance outcomes after anterior cruciate ligament reconstruction (ACLR) depend on the published literature. However, critical appraisal of the validity and biases in these studies is required to understand how ACLR affects an athlete's ability to return to sport, the athlete's sport-specific performance, and his or her ability to achieve preinjury levels of performance.
Purpose: This review identifies the published prognostic studies evaluating sport-specific performance outcomes after ACLR. A risk of bias assessment and summaries of return to sport and career longevity results are provided for each included study.
Study design: Systematic review.
Methods: Electronic databases (Ovid MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and PUBMED) were searched via a defined search strategy with no limits, to identify relevant studies for inclusion in the review. A priori defined eligibility criteria included studies measuring sport-specific performance within an athlete's sport, before and after primary ACLR. Reference lists of eligible studies were hand-searched for additional relevant studies. Data extraction was performed by use of a standardized spreadsheet. Each included study was assessed by use of 6 bias domains of the Quality in Prognosis Studies tool to critically appraise study participation, study attrition, prognostic factors, outcome measurement, confounders, and statistical analysis and reporting. Two authors independently performed each stage of the review and reached consensus through discussion.
Results: Fifteen pertinent prognostic studies evaluated sport-specific performance outcomes and/or return to play after ACLR for athletes participating in competitive soccer, football, ice hockey, basketball, Alpine ski, X-Games ski and snowboarding, and baseball. Twelve of these studies were considered to have a high level of bias.
Conclusion: This review demonstrated that most high-performance or professional athletes returned to their preinjury level of sport after ACLR. The bulk of evidence suggests there was a measurable decrease in performance statistics, although this is highly sport-specific. A paucity of literature is available that addresses sport-specific performance in athletes after ACLR. This review has determined that the available literature is highly biased and must be read with caution.
Clinical relevance: By better understanding the validity and biases in the published literature, physicians can provide more informed prognoses about return to sport-specific performance after ACLR while considering risk factors relevant to their patients.
Registration: CRD42016046709 (International Prospective Register of Systematic Reviews, https://www.crd.york.ac.uk/prospero/ ).
Keywords: ACL; anterior cruciate ligament; baseball; basketball; football; hockey; knee; reconstruction; return to sport; ski; snowboard; soccer; sport-specific performance.