The purpose of this study was to evaluate the clinical results of a newly designed prosthesis to replace the body of the talus in patients with aseptic necrosis. Between 1999 and 2006, 22 tali in 22 patients were replaced with a ceramic prosthesis. A total of eight patients were treated with the first-generation prosthesis, incorporating a peg to fix into the retained neck and head of the talus, and the remaining 14 were treated with the second-generation prosthesis, which does not have the peg. The clinical results were assessed by the American Orthopaedic Foot and Ankle Society ankle/hindfoot scale.

The mean follow-up was 98 months (18 to 174). The clinical results of the first-generation prostheses were excellent in three patients, good in one, fair in three and poor in one. There were, however, radiological signs of loosening, prompting a change in design. The clinical results of the second-generation prostheses were excellent in three patients, good in five, fair in four and poor in two, with more favourable radiological appearances. Revision was required using a total talar implant in four patients, two in each group.

Although the second-generation prosthesis produced better results, we cannot recommend the use of a talar body prosthesis. We now recommend the use of a total talar implant in these patients.

We carried out 123 consecutive total ankle replacements in 111 patients with a mean follow-up of four years (2 to 8). Patients with a hindfoot deformity of up to 10° (group A, 91 ankles) were compared with those with a deformity of 11° to 30° (group B, 32 ankles). There were 18 failures (14.6%), with no significant difference in survival between groups A and B. The clinical outcome as measured by the post-operative American Orthopaedic Foot and Ankle Surgeons score was significantly better in group B (p = 0.036). There was no difference between the groups regarding the post-operative range of movement and complications. Correction of the hindfoot deformity was achieved to within 5° of neutral in 27 ankles (84%) of group B patients. However, gross instability was the most common mode of failure in group B. This was not adequately corrected by reconstruction of the lateral ligament.

Total ankle replacement can safely be performed in patients with a hindfoot deformity of up to 30°. The importance of adequate correction of alignment and instability is highlighted.