The Swedish ankle arthroplasty register -: An analysis of 531 arthroplasties between 1993 and 2005

Background Whether or not ankles can be replaced with reasonable safety has been the subject of debate. We present the results of a nationwide series of total ankle arthroplasties. Patients and methods All Swedish hospitals that implant or have implanted modern three-component ankle prostheses reported demographic data and date of index and revision surgery to a central register. After the data had been introduced into a database, prosthetic survival rates with exchange or permanent extraction of components as endpoint were calculated. Results Of the 531 prostheses implanted, 101 had been revised by June 15, 2006. The overall survival rate at 5 years was 0.78 (95% CI: 0.74-0.82). For the three surgeons who had inserted the majority of the STAR ankles, the survival rates became significantly higher after the first 30 cases had been performed and was estimated to be 0.86 (0.80-0.93) at 5 years. Lower age at index surgery implied increased risk of revision whereas diagnosis or gender did not. Interpretation Ankle replacement is a valuable alternative to arthrodesis. However, replacing an ankle is a demanding procedure and the survival is not comparable to that after hip or knee replacement. It is obvious that with increasing experience, the results-including prosthetic survival-will improve.