Functional Outcomes of Unstable Ankle Fractures in Adolescents.

Abstract

The purpose of this study was to describe the functional outcomes and complications of unstable supination external rotation (SER) and pronation external rotation (PER) ankle fractures in adolescents. A secondary outcome was to compare functional outcomes of SER stage IV injuries that were treated definitively with closed reduction and cast application to a similar group of minimally displaced fractures treated with open reduction and internal fixation (ORIF). A retrospective review of adolescents aged 10 to 18 years with unstable ankle fractures treated at a single institution between 2009 and 2017 was conducted. All patients had functional outcomes data from the Foot and Ankle Ability Measure obtained at a minimum of 1-year follow-up. In total, 67 adolescents (41 SER, 26 PER) were included (mean follow-up: 52.3±24.8 mo). A total of 56 were treated with ORIF and 11 were closed reduced and casted. No patients treated nonsurgically had a loss of reduction and none required subsequent surgical intervention. Preoperative radiographic predictors of syndesmotic injury (>6 mm of tibiofibular clear space or <2 mm of tibiofibular overlap) were not sensitive and only moderately specific predictors of intraoperative syndesmotic injury. There was no difference in functional outcome between the 11 SER stage IV fractures treated nonoperatively and a group of minimally displaced SER injuries treated with ORIF. Patients with open or partially open physes had better functional outcomes. Patients with syndesmotic injuries, medial malleolus fractures, or fracture-dislocations were not associated with lower functional outcome scores in our adolescent cohort. Unstable SER and PER injuries in adolescents have favorable functional outcomes at intermediate-term follow-up, though a minority continue to have impaired ankle function. Minimally displaced SER stage IV injuries with near anatomic alignment after closed reduction can be successfully treated with continued closed management, and have no difference in functional outcomes compared with similar injuries treated with ORIF. Level III.