Obesity Increases Risk of Loss of Reduction After Casting for Diaphyseal Fractures of the Radius and Ulna in Children: An Observational Cohort Study.

OBJECTIVES

To determine if high body mass index (BMI) increases the risk of loss of reduction (LOR) following closed reduction and casting for displaced concomitant fractures of the radial and ulnar shafts in pediatric patients.

DESIGN

Retrospective cohort study.

SETTING

A single, tertiary care, urban children's hospital.

PATIENTS/

PARTICIPANTS

Pediatric patients 2-18 years of age with closed, displaced, concomitant diaphyseal fractures of the radius and ulna (OTA/AO 22-A3) who underwent closed reduction and casting at the study site.

MAIN OUTCOME MEASURES: BMI percentile of ≥95 was defined as obese. For nonobese patients, BMI percentile of ≥85 was defined as overweight. BMI percentile category, fracture angulation, sex, age, fracture location, and number of follow-up visits were recorded. Radiographs and health records were reviewed to note clinical and radiographic cases of LOR. The primary outcome was LOR (clinical or radiographic).

RESULTS

Overall, 124 subjects (74 male and 50 female subjects) underwent acceptable closed reduction and casting. Median patient age was 7.6 years (range, 2.2-17.8 years). There were 14 cases of LOR. LOR rates were 7.2%, 16.7%, and 44.4% for the nonoverweight, overweight, and obese cohorts, respectively (P = 0.005). Regression analysis revealed that LOR was positively associated with higher BMI category (odds ratio for overweight 4.49; P = 0.082; odds ratio for obese 7.52; P = 0.020) and patient age in years (odds ratio, 1.38; P = 0.001).

CONCLUSIONS

Given the high risk of LOR in overweight and obese children with displaced concomitant fractures of the radial and ulnar shafts, our findings suggest that attentive and frequent follow-up is warranted. In these patients, the initial reduction should be closely scrutinized, and a lower threshold for surgical fixation may be considered.

LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.