Intermediate-term Experience With the STAR Total Ankle in the United States

Abstract

Background: Limited intermediate and no real long-term follow-up data have been published for total ankle arthroplasty (TAA) in the United States. This is a report of clinical follow-up data of a prospective, consecutive cohort of patients who underwent TAA by a single surgeon from 1999 to 2013 with the Scandinavian Total Ankle Replacement (STAR) prosthesis. Methods: Patients undergoing TAA at a single US institution were enrolled into a prospective study. These patients were followed at regular intervals with history, physical examination, and radiographs; American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot Scale scores were obtained and recorded. Primary outcomes included implant survivability and functional outcomes scores. Secondary outcomes included perioperative complications such as periprosthetic or polyethylene fracture. Between 1999 and 2013, a total of 138 STAR TAAs were performed in 131 patients; 81 patients were female. The mean age at surgery was 61.5 ± 12.3 years (range, 30-88 years). The mean duration of follow-up for living patients who retained both initial components at final follow-up was 8.8±4.3 years (range 2-16.9 years). Results: The mean change in AOFAS Ankle-Hindfoot scores from preoperative to final follow-up was 36.0 ± 16.8 ( P < .0001). There were 21 (15.2%) implant failures that occurred at a mean 4.9 ± 4.5 years postoperation. Ten polyethylene components in 9 TAAs (6.5%) required replacement for fracture at an average 8.9 ± 3.3 years postoperatively. Fourteen patients died with their initial implants in place. Conclusion: This cohort of patients with true intermediate follow-up after TAA with the STAR prosthesis had acceptable implant survival, maintenance of improved patient-reported outcome scores, and low major complication rates. Level of Evidence: Level IV, case series.