We report the long-term clinical and radiological outcomes of a consecutive series of 200 total ankle arthroplasties (TAAs, 184 patients) at a single centre using the Scandinavian Total Ankle Replacement (STAR) implants. Between November 1993 and February 2000, 200 consecutive STAR prostheses were implanted in 184 patients by a single surgeon. Demographic and clinical data were collected prospectively and the last available status was recorded for further survival analysis. All surviving patients underwent regular clinical and radiological review. Pain and function were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot scoring system. The principal endpoint of the study was failure of the implant requiring revision of one or all of the components. Kaplan–Meier survival curves were generated with 95% confidence intervals and the rate of failure calculated for each year.Aims
Patients and Methods
Between 2002 and 2008, 130 consecutive ankles were replaced with an hydroxyapatite (HA) and titanium-HA-coated Ankle Evolutive System total ankle prosthesis. Plain radiographs were analysed by two independent observers. Osteolytic lesions were classified by their size and location, with cavities >
10 mm in diameter considered to be ‘marked’. CT scanning was undertaken in all patients with marked osteolysis seen on the plain radiographs. Osteolytic lesions were seen on the plain films in 48 (37%) and marked lesions in 27 (21%) ankles. The risk for osteolysis was found to be 3.1 (95% confidence interval 1.6 to 5.9) times higher with implants with Ti-HA porous coating. Care should be taken with ankle arthroplasty until more is known about the reasons for these severe osteolyses.
