Multiligament Knee Injuries in the Pediatric Population: A Systematic Review

BACKGROUND: Multi-ligamentous knee injuries (MLKI) in pediatric patients generally occur due to high-energy mechanisms, exhibiting unique injury patterns when compared to adults. Further understanding of the injury patterns, functional outcomes, and post-surgical complications in pediatric patients sustaining MLKI is warranted. HYPOTHESIS/PURPOSE: To systematically review the literature to evaluate causes and outcomes of MLKIs in pediatric patients. STUDY DESIGN: Level IV Methods: Studies published in PubMed, Embase, and the Cochrane Library reporting on MLKIs in the pediatric population from inception to January 2026 were identified. Inclusion criteria included studies written in English reporting on pediatric patients (≤18 years) undergoing management of MLKIs, with reported lesion etiology, surgical technique, postoperative complications, reoperations, and any patient-reported outcomes (PROs). RESULTS: Four studies comprising 142 patients with a weighted mean follow-up of 41.2 months (range 9.5-204) were identified. The weighted mean patient age and BMI were 16.2 years (range 6-18) and 24.9 kg/m2 (range 17.9-41.6), respectively, with 69.7% (n=99/142) of patients being male. The most common injury mechanism was sports-related (70.6%, n=96/136). The posterolateral corner (PLC) was the most commonly injured structure in 71.1% (n=101/142) of patients, followed by injuries to the posterior cruciate ligament (PCL; 66.2%, n=94/142) and anterior cruciate ligament (ACL; 57.7%, n=82/142). Surgical reconstruction was performed in 96.0% (n=97/101) of PLC-involved injuries, 98.9% (n=93/94) of PCL injuries, 98.8% (n=81/82) of ACL injuries, and 48.4% (n=15/31) of MCL injuries. Repair was performed in 4.0% (n=4/101) of PLC injuries, 1.1% of PCL injuries (n=1/94), 1.2% (n=1/82) of ACL injuries, and 38.7% (n=12/31) of MCL injuries. Complications were reported in 36% (n=19/53) of patients, most commonly stiffness (11.3%, n=6/53) and reconstruction failure (5.7%, n=3/53). Revision procedures were reported in 7.5% (n=4/53) of patients. CONCLUSION: MLKIs in pediatric patients are most commonly reported following sport-related mechanisms, with the PLC and PCL most frequently involved. Surgical reconstruction is more frequently reported when compared to repair procedures, with complications and revision surgery reported in 36% and 7.5% patients, respectively.