Background Obese children reportedly have an increased risk of sustaining musculoskeletal injuries compared with their normal-weight peers. Obese children are at greater risk for sustaining fractures of the forearm, particularly from low-energy mechanisms. Furthermore, obesity is a risk factor for sustaining an extremity fracture requiring surgery. However, it is unclear what role obesity plays in fractures about the distal humerus. Questions/purposes We therefore asked whether (1) children who sustain lateral condyle (LC) fractures have a higher body mass index (BMI) as compared with those with supracondylar (SC) humerus fractures; and (2) children with a higher BMI sustain more severe fractures regardless of fracture pattern. Methods We retrospectively reviewed 992 patients: 230 with LC injuries and 762 with SC fractures. We determined BMI and BMI-for-age percentiles. Fracture types were classified by the systems proposed by Weiss et al. (LC fractures) and Wilkins (SC fractures). Results The LC group had both a higher mean BMI and BMI-for-age percentile than the SC group as well as had more obese patients (37% versus 19%).