Arthrodesis for septic arthritis of the ankle: risk factors and complications

Septic ankle joint arthrodesis is a good therapeutic option in cases of infection after trauma or orthopedic surgical procedures. Many different procedures have been described, but external fixation seems to be standard. Aim of this study is to identify risk factors for complications in septic ankle joint arthrodesis with the external AO frame fixator. Patients who received septic ankle joint arthrodesis between January 2008 and December 2012 were included in this study. Patients were evaluated clinically and with radiographs or CT scans. Follow-up of 74 of 79 patients with an external AO frame fixator could be evaluated; follow-up was 411 days (105-991). The mean age at surgery was 57.7 years (19-87). At this time, complications occurred in 41 patients (52 %) with wound healing problems (17 patients, 22 %) and non-union (12 patients, 15 %), and some needed surgical revision. In our collective, men had a significant higher non-union rate (p = 0.031), age or BMI showed no difference. Patients with diabetes and alcohol consumption showed a higher risk for complications (p = 0.049 and p = 0.031, respectively). 62 % of primary arthrodesis showed union, whereas in the case of revision, arthrodesis only 39 % showed union. Septic ankle joint arthrodesis with the external AO frame fixator is a probable tool to achieve union. This study showed that there is a high complication rate and some risk factors for complications could be identified. A blinded and prospective study is needed to compare intramedullary nailing and external fixation to evaluate the possible advantage of intramedullary devices in septic ankle arthrodesis.