Incidence of Complications and Risk Factors for Nonunion After Ankle Fracture in Diabetes Mellitus.

BACKGROUND

To evaluate complications and risk factors for nonunion in patients with diabetes after ankle fracture.

METHODS

We conducted a retrospective study of 139 patients with diabetes and ankle fractures followed for 1 year. We evaluated the incidence of wounds, infections, nonunions, Charcot's arthropathy, and amputations. We determined Fracture severity (unimalleolar, bimalleolar, trimalleolar), nonunion, and Charcot's arthropathy from radiographs. Nonunion was defined as a fracture that did not heal within 6 months of fracture. Analysis of variance was used to compare continuous variables, and χ2 tests to compare dichotomous variables, with α = 0.05. Logistic regression was performed with a binary variable representing nonunions as the dependent variable.

RESULTS

Complications were common: nonunion (24.5%), Charcot's arthropathy (7.9%), wounds (5.2%), wound site infection (17.3%), and leg amputation (2.2%). Patients with nonunions were more likely to be male (55.9% versus 29.5%; P = .005), have sensory neuropathy (76.5% versus 32.4%; P < .001), have end-stage renal disease (17.6% versus 2.9%; P < .001), and use insulin (73.5% versus 40.1%; P < .001), β-blockers (58.8% versus 39.0%; P = .049), and corticosteroids (26.5% versus 9.5%; P = .02). Among patients with nonunion, there was an increased risk of wounds (odds ratio [OR], 3.3; 95% confidence interval [CI], 1.46-7.73), infection (OR, 2.04; 95% CI, 0.72-5.61), amputation (OR, 7.74; 95% CI, 1.01-100.23), and long-term bracing (OR, 9.51; 95% CI, 3.8-23.8). In the logistic regression analysis, four factors were associated with fracture nonunion: dialysis (OR, 7.7; 95% CI, 1.7-35.2), insulin use (OR, 3.3; 95% CI, 1.5-7.4), corticosteroid use (OR, 4.9; 95% CI, 1.4-18.0), and ankle fracture severity (bimalleolar or trimalleolar fracture) (OR, 2.5; 95% CI, 1.1-5.4).

CONCLUSIONS

These results demonstrate risk factors for nonunions: dialysis, insulin use, and fracture severity after ankle fracture in patients with diabetes.