Clinical and Radiographic Outcomes of Revision Total Ankle Arthroplasty using a Revision Ankle System

Abstract

Category: Ankle Arthritis; Ankle Introduction/Purpose: With the growing popularity of total ankle arthroplasty (TAA), revision surgeries are inevitable and expected to significantly increase over the next decade. Revision TAA remains a significant challenge with high complication rates. No previous study has reported on outcomes following revision TAA using an implant designed specifically for revisions. Theoretical benefits of a revision-specific ankle system include tibial and talar fixation/stability, restoration of joint height, coverage of bone loss/defects, and maximal talar coverage. The purpose of this study was to investigate radiographic and clinical outcomes at a minimum of 2 years following revision TAA using a revision-specific ankle system. Methods: Patients who underwent a revision TAA using a revision-specific ankle system (Invision, Stryker, Kalamazoo, MI) between January 2016 and December 2020 were eligible to be included in this study. Patients with less than 2-year follow-up and unwilling to return to clinic were excluded. Overall, 25 patients met inclusion criteria. Indications for revision TAA (Table 1) included talar loosening (n = 6), tibial loosening (n = 7), talar subsidence (n = 6), re-implant after infection (n = 4), instability (n = 3), periprosthetic fracture (n = 2), and severe osteolysis (n = 2). Medians and interquartile ranges (IQRs) were reported since the data was not normally distributed. Clinical and radiographic outcomes, complications, reoperations, and implant survival was recorded. Results: Implant survival was noted in 80% of patients (20/25) at a median of 3.8 years following revision TAA. Index revision was most commonly performed for implant loosening (tibia 28%, talus 24%), talar subsidence (24%), or re-implant after infection (16%). Foot and Ankle Ability Measure (FAAM) Activities of Daily Living and Sports scores were 53.9 (IQR 46.4, 71.4) and 37.5 (IQR 21.9, 46.9), respectively at final follow-up. There was evidence of talar loosening in 3 patients (12%) and talar subsidence in 5 patients (20%) on final radiographs. Reoperation rate at final follow-up was 48%, most commonly for talar loosening/subsidence (n= 2), tibial loosening (n = 3), septic TAA (n = 1), medial/lateral gutter impingement (n = 2), and instability (n = 2). Conclusion: At a minimum follow-up of 2 years, 80% of patients retained their metal revision TAA, but reoperation rates were high with 48% of patients requiring an additional procedure most commonly for implant loosening, talar subsidence, gutter impingement, or instability. Revision TAA using a revision-specific ankle system is a viable option for patients with a failed TAA. Physicians and patients should be aware that revision TAA remains a significant challenge with a high risk of complication and reoperation rates.