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.

Intoduction: Ankle arthrodesis is the most commonly used procedure for the painful stiff ankle. A unilateral ankle arthrodesis results in good function, provided the subtalar and midtarsal joints are normal and provide a compensatory mechanism. The disadvantages of arthrodesis include the need for prolonged immobilisation and a pseudoarthrosis rate up to 10%. Superiority of arthroplasty over artrodesis has been provided by Kofoed and Stirrup (1994). In a series of 26 patients 13 patients with 14 arthrodesis were compared with 13 patients with 14 arthroplasties with follow-up of 84 months, arthroplasty gave better pain relief, better function and a lower infection rate. Results: We hahe implanted 36 STAR total ankle prosthesis on patients with mean follow-up of 22 (6–60) months. The mean age of patients was 47 (20–78) years at operation. The Indication for operation was Rheumatoid Arthritis in 23 patients and Post traumatic arthrosis in 13 patients. The mean Kofoed score before operation was 40 (12–73) points and at follow-up study it was 81 (44–98) points, P< 0.001. Result was excellent in 14 patients, good in 15 patients, fair in 2 patients and poor in 5 patients. The mean motion in the ankle at follow-up study was 30 (10–50) degrees. At follow-up study the mean valgus in the x-rays was 0.5 (0–7) degrees and Varus 1.8 (0–8) degrees. Radiolucent lines were obtained on 4 patients around the tibial component at the follow-up study. There was no difference in the results between rheumatoid patients and post-traumatic patients. Conclusions: Third generation ankle arthroplasty has moved from experimental procedure to that of worthwhile and durable solution