Total ankle replacement in association with hindfoot fusion : outcome and complications

We report the clinical and radiological outcome of total ankle replacement performed in conjunction with hindfoot fusion or in isolation. Between May 2003 and June 2008, 60 ankles were treated with total ankle replacement with either subtalar or triple fusion, and the results were compared with a control group of 288 ankles treated with total ankle replacement alone. After the mean follow-up of 39.5 months (12 to 73), the ankles with hindfoot fusion showed significant improvement in the mean visual analogue score for pain (p > 0.001), the mean American Orthopaedic Foot and Ankle Society score (p > 0.001), and the mean of a modified version of this score (p > 0.001). The mean visual analogue pain score (p = 0.304) and mean modified American Orthopaedic Foot and Ankle Society score (p = 0.119) were not significantly different between the hindfoot fusion and the control groups. However, the hindfoot fusion group had a significantly lower mean range of movement (p = 0.009) and a higher rate of posterior focal osteolysis (p = 0.04). Both groups showed various complications (p = 0.131) and failure occurring at a similar rate (p = 0.685). Subtalar or triple fusion is feasible and has minimal adverse effects on ankles treated with total ankle replacement up to midterm follow-up. The clinical outcome of total ankle replacement when combined with hindfoot fusion is comparable to that of ankle replacement alone. Thus, hindfoot fusion should be performed in conjunction with total ankle replacement when indicated.