The Salto Mobile-Bearing Total Ankle Arthroplasty: Survivorship, Radiologic, and Clinical Outcomes at an Average 9-Year Follow-Up

Abstract

Background: Total ankle arthroplasty (TAA) remains an excellent treatment option for end-stage ankle osteoarthritis. Questions remain regarding the superiority of either fixed- or mobile-bearing implants because of equipoise in the literature and a paucity of long-term follow-up. We present results of the Salto mobile-bearing TAA, aiming to add to the literature for longer-term follow-up of this mobile-bearing TAA and investigate the survivorship and patient satisfaction with this implant. Methods: TAA was performed in 91 consecutive ankles (87 patients) in an independent, prospective, single-surgeon study. The minimum follow-up was set at 5 years. Implant survival, patient-reported outcome measures (PROMs), and radiographic outcomes are presented at a mean of 9.1 years (range 5-18 years). Results: Nine ankles (9 patients) were lost to follow-up or were unable to comply. Eighty-two ankles (78 patients) were included with a mean age of 69.5 years at the time of their operation. Six of 82 ankles (7.3%) underwent revision of any of the components. Four were revisions involving the metallic components to fusion or revision TAA, all within 5 years of the index procedure. Three ankles (3.7%) underwent reoperations. With all-cause revision of any component (including the polyethylene liner) as an endpoint, implant survival was calculated using Kaplan-Meier curves as 95.0% at 5 years and 93.2% at 10 years. Reported PROMs were very high and we found no progressive linear lucencies, cysts, or subsidence in TAAs other than in those that underwent revision or reoperation. Conclusion: Our study of 82 Salto mobile-bearing TAAs found commendable survivorship, along with robust radiographic and patient-reported outcomes at an average of 9 years, with survivorship rates comparable to those reported for fixed-bearing implants.