Total ankle arthroplasty with the Agility prosthesis: clinical and radiographic evaluation.

BACKGROUND

Although ankle arthrodesis remains a standard operative procedure for disabling ankle arthritis, it has potential long-term problems. Total ankle arthroplasty offers preserved joint motion and may be a more favorable option in select patients. The purpose of this study was to report the intermediate-term clinical and radiographic results of total ankle arthroplasty using the Agility prosthesis.

METHODS

We retrospectively reviewed the results of total ankle arthroplasty in 41 consecutive patients (43 ankles). Evaluation included preoperative and postoperative questionnaires, physical examination, and radiographs.

RESULTS

At the time of followup, 38 patients (40 ankles) were available for review. The most common preoperative diagnoses included posttraumatic arthritis (24 of 40 ankles, 60%) and rheumatoid arthritis (eight of 40 ankles, 20%). Average age at surgery was 63 (range 32 to 85) years. Average followup was 44.5 (range 26 to 64) months. Preoperative and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scores averaged 33.6 and 83.3, respectively, demonstrating significance (p < 0.001). Postoperative Medical Outcomes Study Short Form-36 (SF-36) Physical Component Summary (PCS) and Mental Component Summary (MCS) scores averaged 49.5 and 56.1, respectively. Although 34 of 40 ankles demonstrated radiographic lucency or lysis, the degree of involvement varied. Migration or subsidence of components was noted in 18 ankles. Overall, 37 of 38 patients were satisfied with the outcome of their surgery and would have the same procedure under similar circumstances.

CONCLUSIONS

Agility total ankle arthroplasty results in a favorable clinical outcome and patient satisfaction in most patients at intermediate-term followup. However, total ankle arthroplasty is associated with potential complications and the need for subsequent operative intervention. Radiographic followup commonly reveals periprosthetic lucency, lysis, and component migration or subsidence, but this does not appear to adversely affect the intermediate-term clinical outcome. The long-term consequences of such radiographic findings are of concern, and surgeons and patients choosing this procedure need to be cautious.