Determinants of functional outcome following ankle fracture.

Objectives: To assess the patient and injury characteristics that impact functional outcomes after ankle fracture.

Design: Retrospective study.

Setting: Urban level I trauma center.

Patients/participants: One thousand patients underwent fixation of ankle fracture (AO/OTA 44) between 2006 and 2015. Four hundred sixteen completed functional outcome surveys by telephone or mail at a mean of 5.9 years after injury.

Intervention: Open reduction internal fixation.

Main Outcome Measure: Foot Function Index (FFI) and Short Musculoskeletal Function Assessment (SMFA).

Results: Mean age was 46.7 years, with 46.2% male. Higher (worse) FFI scores were seen in tobacco users (38.9 vs 30.1), recreational drug users (45.9 vs 32.7), and the morbidly obese (52.0 vs 30.6), all  < .005. Higher (worse) SMFA dysfunction and bothersome scores were also seen in these groups, and in females and alcohol users. Multiple regression analysis identified female gender, obesity, tobacco and alcohol use, complications, secondary procedures, and multiple additional injuries as independent predictors of higher scores (all  < .04). Fracture patterns, open fracture, and development of arthritis had no impact on FFI or SMFA scores.

Conclusion: Patient characteristics, not under surgeon-control, such as female sex, obesity, and substance use, appear to contribute to patient-reported functional outcome scores more than injury characteristics.

Level Of Evidence: Level 3, prognostic.