Midterm Outcomes of the Salto Talaris Total Ankle Arthroplasty

Abstract

Category: Ankle Arthritis; Ankle Introduction/Purpose: Total ankle arthroplasty (TAA) has become an accepted alternative to ankle arthrodesis for end-stage ankle arthritis and has seen significantly increased utilization in the past decade1. The Salto Talaris total ankle prosthesis has shown excellent short-term and mid-term survivorship results since its FDA approval in the U.S. in 20062,3. At a minimum of five-year follow-up, the currently reported midterm survivorship has ranged from 93.3% to 100% with equally satisfactory clinical outcomes as evidenced in short-term outcome studies4–8. The purpose of this study is to report the outcomes of one of the largest cohort of patients who underwent a Salto Talaris total ankle arthroplasty with a minimum of five-year follow-up. Methods: 103 Salto Talaris TAA patients with 5-view weight-bearing series of radiographs and minimum follow-up time of 5 years since index surgery were included. Age at time of surgery, gender, body mass index, diagnosis, diabetes status, and tobacco use were collected through chart review. Radiographic imaging was assessed at the most recent follow-up for evidence of radiolucency and osteolysis as previously described9. Range of motion was assessed on plantarflexion and dorsiflexion views on sagittal radiographs as previously described10. The Foot and Ankle Ability Measure (FAAM) and Visual Analog Scale for pain (VAS) scores were obtained at the most recent follow up visit and compared with preoperative scores. Baseline characteristics were compared between groups using Wilcoxon rank-sum test for continuous data or Fisher exact test for discrete data. Survivorship probability was calculated using a Kaplan-Meier analysis for revisions and reoperations. Revisions were defined as exchange or removal of metal component. Results: The survivorship for revision surgery was 93.2% (95% CI [89.8,98.8]). 5 out of the 7 patients requiring revision surgery experienced talar subsidence, 1 patient experienced an infection, and 1 patient experienced lateral impingement. The survivorship for reoperation was 90.2% (95% CI [83.4-95.4]). 5 out of the 10 patients requiring reoperation experienced pain from impingement, 2 experienced periprosthetic fractures, 1 experienced infection, and 2 experienced osteolytic cysts. At last follow- up, the FAAM-ADL, FAAM-Sport, and VAS pain scores were improved from preoperatively. The average range of motion at last follow-up was 31.6 degrees. On the AP view, radiolucency and osteolysis were most frequently detected in zones 3 and 4, while on the lateral view they were most frequently seen in zones 2 and 6. Conclusion: Patients undergoing Salto Talaris prosthesis showed improvements in patient-reported outcomes with satisfactory survival rates.