Abstract / Summary
Importance: Anterior cruciate ligament (ACL) injuries in pediatric and adolescent athletes are increasingly common, and ACL reconstruction (ACLR) carries a high risk of reinjury in this population. Graft selection and return to sport (RTS) timing are potentially modifiable determinants of reinjury risk, and the rapid accumulation of new evidence continues to challenge established dogma, warranting an updated synthesis of their combined influence in skeletally immature patients. Objectives: This systematic review will establish the impact of autograft type and RTS timing on reinjury rates, including ipsilateral graft rupture and contralateral ACL injury, following primary pediatric ACLR. A secondary objective is to examine the role of lateral extra-articular tenodesis (LET) augmentation as a modifier of these outcomes. Evidence review: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and registered with PROSPERO (ID CRD420251167612). PubMed, Embase, Web of Science, and the Cochrane Library were searched from inception to August 2025. Eligible studies included pediatric patients (≤19 years) undergoing primary ACLR with reported outcomes on graft failure, contralateral injury or RTS. Prospective and retrospective cohort studies, case–control studies, case series (n > 10), and randomized controlled trials (RCTs) were included. Two independent reviewers assessed methodological quality using the Modified Coleman Methodology Score (MCMS), and certainty of evidence for principal outcomes using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). Findings: In total, 51 studies encompassing 4153 patients were included. Study quality was predominantly fair (mean MCMS 58.5; 13.7% were graded as poor). Hamstring tendon (HT) autograft was the most frequently studied graft, with rerupture rates of 0%-34.6% across studies. In all comparative studies, HT was associated with higher re-rupture rates than bone-patellar tendon-bone (BTB; range 0%-10%) or quadriceps tendon (QT; range 0%-10%) autograft. LET augmentation consistently reduced rerupture risk across all graft types, with HT + LET demonstrating 0%-5.3% rerupture versus 11.9%-15% for HT and QT + LET reporting 0% versus 7.7% for QT alone in comparative studies. Reported RTS rates ranged from 42.2% to 100%, although definitions varied between return at any level and return to the preinjury level of sport, limiting direct comparison between studies. Mean RTS timing ranged from 6.4 to 11.6 months; a restrictive protocol delaying RTS beyond 9 months was associated with lower revision rates in one comparative study. Functional outcomes were broadly favorable, but reporting was heterogeneous. Conclusion and relevance: In pediatric ACLR, HT autograft is associated with higher reported rerupture rates than BTB (in skeletally mature patients) or QT in comparative studies. LET augmentation was associated with lower rerupture rates without compromising RTS or functional outcomes. Current pediatric evidence does not justify routine RTS before 9 months without objective functional clearance. The evidence base is dominated by retrospective case series of moderate quality, and no RCT has directly compared graft selection or RTS timing in skeletally immature patients, highlighting an urgent need for prospective, adequately powered studies in this population. Level of evidence: Level III.