Adolescent arm wrestling–related medial epicondyle fractures: carrying angle and body mass index as associated anatomic and anthropometric factors

Medial epicondyle fractures during arm wrestling are rare but potentially debilitating injuries in adolescents, with previous reports limited to small case series of fewer than 10 patients. The anatomic and anthropometric factors predisposing adolescents to this injury pattern remain poorly understood. This study aimed to identify factors associated with arm wrestling-related medial epicondyle fractures across multiple institutions. This multi-institutional case–control study was conducted across six hospitals of a single academic medical center over 14 years (2010–2024). Nineteen adolescents with arm wrestling-related medial epicondyle fractures were identified and compared with 19 age- and sex-matched controls with supracondylar fractures. Radiographic measurements included carrying angle, Baumann’s angle, and skeletal maturity (Sauvegrain score). Body mass index (BMI) was calculated from height and weight data. Univariate and multivariate logistic regression analyses were performed to identify independent associated factors. The medial epicondyle fracture group demonstrated significantly greater carrying angle (18.78° ± 2.91° vs. 14.28° ± 2.55°, p < 0.001; Cohen’s d = 1.64) and higher BMI (21.01 ± 2.33 vs. 17.10 ± 2.42 kg/m 2 , p < 0.001), while age, height, and skeletal maturity did not differ between groups (all p > 0.2). Multivariate logistic regression identified carrying angle (adjusted OR = 1.593, 95% CI 1.060–2.393, p = 0.025) and BMI (adjusted OR = 1.858, 95% CI 1.081–3.196, p = 0.025) as independent associated factors. The model explained 54.2% of the variance in fracture occurrence (McFadden’s pseudo R 2 = 0.542). Increased carrying angle and elevated BMI are independently associated with medial epicondyle fractures during arm wrestling in adolescents. These readily measurable characteristics distinguish affected adolescents from those with supracondylar fractures. This multi-institutional approach enabled characterization of factors associated with a rare injury pattern.