Successful Outcomes with Nonoperative Treatment and Immediate Weightbearing Despite Stress-Positive Radiographs in Isolated Distal Fibula (OTA/AO 44B) Fractures.

Abstract

Objectives: To determine if a nonoperative management protocol results in equivalent outcomes in isolated OTA/AO 44B (Weber B) fractures without initial medial clear space (MCS) widening regardless of stress radiography findingsDesign: Prospective cohortSetting: Level 1 academic trauma centerPatients/Participants: Sixty-nine patients with isolated OTA/AO 44B fractures and MCS ≤ 4 mm on initial non-weightbearing injury radiographs over a 4-year periodIntervention: nonoperative management of isolated OTA/AO 44B fractures without initial MCS widening > 4 mmMain Outcome Measurements: MCS measurements on weightbearing radiographs at first follow up, six weeks, 12 weeks, and six months post-injury; American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scoresResults: None of the 38/69 (55%) patients with widening on gravity stress radiographs demonstrated persistent widening with weightbearing radiographs at any time point. Mean MCS measurement differences between the two cohorts were statistically significant for all time points (p=0.012), however with a model adjusted mean MCS value of 2.7 mm for the non-widening cohort and 2.9 mm for the widening cohort, these are not clinically significant. There was no statistically significant difference in overall final AOFAS scores between the two groups (p=0.451). Additionally, statistical equivalence using Schuirmann's two one-sided tests was achieved between the two groups. Both cohorts had mean AOFAS scores representing excellent outcomes at final follow up.Conclusions: Isolated OTA/AO 44B fractures without MCS widening on initial injury radiographs have equivalent outcomes regardless of gravity stress radiography findings when treated nonoperatively. Weightbearing radiographs at initial follow-up are a reliable assessment of ankle stability in these injuries and are an appropriate alternative to painful and time-consuming stress radiography.Level of Evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.