The effect of different methods of stability assessment on fixation rate and complications in supination external rotation (SER) 2/4 ankle fractures

• We compare outcomes of SER type II/IV ankle fractures assessed with different radiographic protocols.
• We compare those assessed with examination under anaesthesia or repeated plain radiographs (EUA/AP) with patients assessed by either gravity stress (GS) or weightbearing radiographs (WB).
• The rate of fixation was 10 times higher in the GS group compared with the WB or EUA/AP group.
• The proportion of patients requiring further surgery or suffering complications was also significantly higher with GS views.

BackgroundDistinguishing stable supination-external rotation (SER) 2 from unstable SER 4 ankle fractures, using standard radiographs, is controversial. Examination under anaesthesia (EUA), gravity-stress (GS) and weight-bearing (WB) radiographs can aid surgical decision-making. We evaluated the effect of three methods of fracture stability assessment.MethodsRadiographs and case-notes of 312 consecutive patients with SER 2/4 fractures were reviewed. We recorded ankle stability assessment (plain film (PF) and EUA vs. GS vs. WB radiographs), management (conservative vs. operative), unplanned surgery and complications.ResultsForty five percent assessed with GS underwent surgery (6% for PF/EUA, 4% for WB; P = 0.0001). Amongst GS patients, 11% underwent additional surgery (0.1% PF/EUA, 0% WB; P = 0.0001). Complications occurred in 2% of the WB group (8% for PF/EUA, 22% for GS; P = 0.007).ConclusionThis study associates GS assessment with higher rates of surgery and complications. Subsequent studies may determine the longer term effect stability assessments have on post-traumatic arthritis.