Childhood obesity as a risk factor for lateral condyle fractures over supracondylar humerus fractures.

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%). Within the LC group, children with Type 3 fractures had a higher BMI that those with Type 1 fractures (19 versus 17). There was a higher percentage of obese patients with Type 3 LC fractures compared with Type 1 and 2 fractures (44% versus 27% and 26%). Among patients with SC fractures, there was no difference among the BMI, BMI-for-age percentiles, or percentage of obese children when analyzed by fracture subtype.
CONCLUSIONS: Obesity places a child at greater risk for sustaining a LC fracture and when these fractures occur, they are often more severe injuries compared with those in nonobese children. LEVEL OF EVIDENCE: Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.