The association of body mass index with complications and functional outcomes after surgery for closed ankle fractures.

AIMS: This study assessed the association of classes of body mass index in kg/m2 (classified as normal weight 18.5 kg/m2 to 24.9 kg/m2, overweight 25.0 kg/m2 to 29.9 kg/m2, and obese ≥ 30.0 kg/m2) with short-term complications and functional outcomes three to six years post-operatively for closed ankle fractures. PATIENTS AND METHODS: We performed a historical cohort study with chart review of 1011 patients who were treated for ankle fractures by open reduction and internal fixation in two hospitals, with a follow-up postal survey of 959 of the patients using three functional outcome scores.
RESULTS: Obese patients had more severe overall complications and higher odds of any complication than the normal weight group, with adjusted odds ratio 1.67 (95% confidence interval (CI) 1.08 to 2.59; p = 0.021) and 1.71 (95% CI 1.10 to 2.65; p = 0.016), respectively. In total 479 patients (54.6%) responded to the questionnaire. Obese patients had worse scores on the Olerud and Molander Ankle Score (p < 0.001), Self-Reported Foot and Ankle Questionnaire (p = 0.003) and Lower Extremity Functional Scale (p = 0.01) than those with normal weight. In contrast, overweight patients did not have worse functional scores than those with normal weight.
CONCLUSION: Obese patients had more complications, more severe complications, and worse functional outcomes three to six years after ankle surgery compared with those with normal weight. Cite this article: Bone Joint J 2017;99-B:1389-98. ©2017 The British Editorial Society of Bone & Joint Surgery.