Sport-specific concomitant injuries, return-to-sport rates and second anterior cruciate ligament (ACL) injuries in adolescents with ACL reconstruction

Objective To evaluate differences in sport-specific concomitant injuries, return-to-sport (RTS), second ACL injuries and Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales after adolescent ACL reconstruction (ACLR) across popular sports. Methods This prospective cohort study included patients aged 10-18 years at ACLR. Demographic and injury-related data and KOOS subscales before ACLR and at the 1 and 2 years follow-ups were obtained. A survey to assess sport-specific outcomes and RTS was sent to eligible patients. Group comparisons were performed between the most popular sports and between females and males. Results Overall, 1392 patients with a mean age of 16.4±1.4 years at ACLR were included. The mean time between ACLR and survey completion was 9.7±4.2 years. The most prevalent type of sport was soccer, followed by handball, floor hockey/field hockey, basketball and other sports. Concomitant injuries (71%) and second ACL injuries (30%; 20% ipsilateral, 13% contralateral) were common across all sports. No significant differences were found in ipsilateral second ACL injuries across sexes and sports. 24% of patients competed at an elite level sport (highest national level of junior sport or higher) for some period after ACLR. 8% of patients did not RTS at all, with females significantly more often without RTS than males (9% vs 4%, p=0.041). Significant improvements were observed in KOOS subscales from baseline to the 1 and 2 years follow-ups for all sports. Conclusion Concomitant injuries are frequently observed after ACL injury in adolescents, with nearly one-third suffering a second ACL injury. While significant improvements in KOOS subscales and return to high-level sports can be expected, better injury prevention is needed after ACLR.