Risk Factors for Concomitant Collateral Ligament Injuries in Children and Adolescents With Anterior Cruciate Ligament Tears

BACKGROUND: Risk factors for concomitant ligament injuries (CLIs) of the lateral collateral ligament (LCL) and medial collateral ligament (MCL) in children and adolescents with anterior cruciate ligament (ACL) tears are unknown. PURPOSE: To determine whether body mass index (BMI), sex, age, and injury mechanism are associated with CLIs in children and adolescents with ACL tears and whether CLIs are associated with meniscal and chondral injuries and a delay to surgery. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: We reviewed the records of patients aged ≤18 years with ACL tears from 2009 through 2013 for sex, age, height, weight, CLI, injury mechanism, intra-articular injury, and time to surgery. Patients were assigned to groups according to the presence of a CLI (CLI group) compared with the presence of an isolated ACL tear (ACL group). BMI was categorized as underweight, normal weight, or overweight/obese. The older group was defined as age ≥14 years for girls and ≥16 years for boys. Logistic regression, Mann-Whitney U tests, and chi-square tests were performed (alpha = 0.05). RESULTS: We included 509 patients (267 girls) with a mean age of 15 years (range, 6-18 years) at the time of injury. There were 396 patients (78%) in the ACL group and 113 patients (22%) in the CLI group (90 with MCL, 11 with LCL, and 12 with both MCL and LCL injuries). Groups had similar proportions of overweight/obese patients (P = .619) and girls (P = .104). Older age (odds ratio [OR], 2.0 [95% CI, 1.3-3.3]) and contact injuries (OR, 2.2 [95% CI, 1.4-3.4]) were associated with CLIs. The CLI group had a higher proportion of chondral injuries (P = .001) but not meniscal injuries (P = .295) and presented to surgery earlier than the ACL group (P = .002). CONCLUSION: Older age and contact injuries were associated with CLIs in children and adolescents with ACL tears, whereas BMI category and sex were not. CLIs were associated with a higher proportion of chondral injuries but not meniscal injuries and were not associated with a delay to surgery.