Total ankle prostheses in rheumatoid arthropathy: Outcome in 52 patients followed for 1-9 years.

BACKGROUND AND PURPOSE: The first generations of total ankle replacements (TARs) showed a high rate of early failure. In the last decades, much progress has been made in the development of TARs, with the newer generation showing better results. We evaluated TARs implanted with rheumatoid arthritis (RA) or juvenile inflammatory arthritis (JIA) as indication.

PATIENTS AND METHODS: 58 total ankle prostheses (Buechel-Pappas and STAR type) were implanted in patients with RA (n = 53) or JIA (n = 5) in 54 patients (4 bilateral). After a mean followup of 2.7 (1-9) years, all patients were reviewed by two orthopedic surgeons who were not the surgeons who performed the operation. Standard AP and lateral radiographs were taken and a Kofoed ankle score was obtained; this is a clinical score ranging from 0-100 and consists of sub-scores for pain, disability, and range of motion.

RESULTS: 2 patients died of unrelated causes. Of the 52 patients who were alive (56 prostheses), 51 implants were still in place and showed no signs of loosening on the most recent radiographs. The mean Kofoed score at follow-up was 73 points (SD 16, range 21-92). 4 patients showed a poor result (score < 50) with persistent pain for which no obvious reason could be found. 5 implants were removed, 4 because of infection and 1 because of aseptic loosening.

INTERPRETATION: Medium-term results of the STAR and BP types of TAR in RA were satisfactory. The main reason for failure of the implant was infection.