MINIMUM 5 YEAR FOLLOW-UP RESULTS OF SCANDINAVIAN TOTAL ANKLE REPLACEMENTS

Abstract

Introduction: Few intermediate term studies have presented data on modern total ankle replacement designs. This independent, prospective study provides clinical and radiographic results for 50 Scandinavian Total Ankle Replacements with at least 5 years follow up.

Methods: 50 consecutive STAR total ankle replacements were performed in 46 patients, aged 33–79 (mean 63) between 1999 and 2002 by a single surgeon. These were prospectively followed up on annually for a mean of 6 years (5–8 years).

Results: 34 replacements were performed for osteoarthritis, the remainder for inflammatory arthropathy. 13 ankles had a preoperative varus or valgus deformity of more than 10 degrees. There were 3 deaths, therefore 47 ankles reviewed.

5 revisions were performed; 2 for stiffness (1 tibial component, 1 insert), 2 for stress fractures (tibial component only) and 1 insert fracture. 3 of these cases required further surgery following their first revision (1 fusion for deep infection, 1 insert exchange for edge loading and one arthoscopic debridement plus calcaneal osteotomy for painful varus deformity).

There were no primary revisions for aseptic loosening or deep infection. 3 radiographs demonstrated non-progressive lucent lines behind the tibial component.

Further surgery was required in 8 other ankles (6 calcaneal osteotomies and 2 arthroscopic debridements). Complete correction of pre-operative deformity was ultimately achieved in all but 4 ankles.

The mean postoperative American Orthopaedic Foot and Ankle Society Score was 77.

Discussion: At a minimum follow up of 5 years after Scandinavian Total Ankle Replacement, all but one of our ankles have well functioning prostheses in situ. However, 13/47 ankles required further surgery of some kind, including 5 component revisions (90% survival).

Conclusion: Total ankle arthroplasty is a reliable procedure for ankle arthrosis at intermediate term follow up. It provides good functional results and symptomatic benefit, although additional operative procedures may be required.