BACKGROUND Multiple studies have documented increased risks associated with treatment of ankle fractures in patients with diabetes mellitus. We reviewed our results in the largest series to date of this complex patient group to determine the frequency of complications. METHODS Eighty-four patients with diabetes had open reduction and internal fixation using standard fixation techniques for acute, closed ankle fractures. The 51 men and 33 women had an average age was 49.3 (22 to 77) years. The average followup was 4.1 years (11 to 97 months). Seventy-five fractures were closed and nine were open. Thirty-nine patients used insulin and 45 used oral hypoglycemics or diet for control of their diabetes. Diabetic complications, including nephropathy, hypertension, peripheral vascular disease, and neuropathy were evaluated. The management of diabetes, fracture classification, and presence of diabetic complications were assessed with chi-square, ANOVA, and univariate logistic regression to determine the presence of statistical significance for these factors. RESULTS Twelve of the 84 patients developed postoperative complications. Ten patients developed infections (eight deep and two superficial). Four of 12 patients with preoperative evidence of peripheral neuropathy developed Charcot arthropathy. Ten of 12 patients who had absent pedal pulses preoperatively developed complications (p<0.0001) and 11 of 12 patients with peripheral neuropathy had complications (p<0.0001). A trend towards complications was noted with nephropathy (two of five patients) and hypertension (nine of 12 patients). Open fractures, insulin dependence, patient age, and fracture classification had no significant effect on outcome. CONCLUSIONS Most patients with diabetes can undergo open reduction and internal fixation of acute ankle fractures without complications. Patients with absent pedal pulses or peripheral neuropathy are at increased risk for complications.