Return to Sport After Pediatric Anterior Cruciate Ligament Reconstruction: A Systematic Review of the Criteria

Background: Postoperative rehabilitation is an important component of recovery after anterior cruciate ligament (ACL) reconstruction (ACLR), facilitating successful return to sport (RTS) by reducing risk factors for repeat injury. Purpose: This systematic review aimed to determine the best protocol for RTS after ACLR in children. Study Design: Systematic review; Level of evidence, 4. Methods: PubMed, Embase, PEDro, SPORTDiscus, and Web of Science databases were searched from October 3, 2014, to November 3, 2022. The inclusion criteria were the pediatric population (<18 years old) after ACLR with clear RTS criteria and/or mean/median time to RTS. Multiligament knee injuries were excluded from this study. The methodologic quality of the included articles was assessed using the methodological index for non-randomized studies (MINORS). The highest possible score was 24 points for comparative studies (ie, a study comparing 2 protocols or more). Noncomparative studies or studies with a single protocol could score a maximum of 16 points as assessed by the MINORS score. Results: The search yielded 1816 titles, and 24 were retained based on the inclusion and exclusion criteria. Every study was published between 2015 and 2022. Among the 24 studies included, 13 were retrospective and 11 were prospective. The mean MINORS score for the noncomparative studies was 13 of 16 (n = 23) and 23 of 24 for the comparative study (n = 1). The studies were categorized into unspecified clearance (n = 10), milestone based (n = 13), and combined time and milestone (n = 1). A total of 1978 patients (57% female) were included in the review. The mean age at ACLR was 14.7 years. The most common endpoint used was graft rupture (0% to 35%). In the unspecified group, the quickest RTS was 5.8 months and the longest was 9.6 months. Statistically significant risk factors for ACL reinjury included younger age and earlier RTS. The latter was a significant contributor to graft failure for combined time-based and milestone-based RTS. In the milestone-based group, the most common criteria were ≥90% limb symmetry measured using hamstring strength, quadriceps strength, and/or hop tests. The mean RTS time was 6.8 to 13.5 months. Conclusion: RTS should be delayed, when possible, especially in the younger population. A combination of quantitative tests and qualitative tests is also recommended. However, optimal RTS criteria have yet to be determined. Future prospective studies should focus on comparing the different times and milestones currently available.