Early-to-Intermediate Clinical and Radiographic Outcomes of the Vantage Total Ankle Arthroplasty

Abstract

Category: Ankle Arthritis Introduction/Purpose: The Vantage total ankle arthroplasty (TAA) features a design based on careful study of arthritic ankles and current ankle biomechanics, with theoretical advantages of a vertically-oriented tibial fixation and a fully congruent talar dome bone-implant interface. In this design-team, single-institution investigation, we report early-to-intermediate term clinical and radiographic outcomes, implant survivorship, and complications of the Vantage TAA. Methods: We retrospectively reviewed prospectively collected data for 278 consecutive patients undergoing Vantage fixed-bearing TAA. Ankles with coronal plane deformity > 25 degrees and suspected poor bone quality were prospectively excluded. Prospectively collected data includes: PROMIS, SF-36, SMFA, VAS and AOFAS hindfoot-ankle scores. Using previously published and commonly accepted evaluation methods, independent radiographic analysis, performed by a non-design surgeon investigator, included pre-operative, 1-year, and most recent follow-up assessments of 2-plane alignment, component position, and the bone- implant interface. A non-design surgeon investigator with dedicated training in statistics performed the statistical analysis using descriptive statistics to report PROM and radiographic measures and Kaplan-Meier survivorship analysis. Results: Mean patient age was 64.8yrs (range:33-86), 44.2% were female, and mean follow-up was 3.1yrs (2.0-5.5). Mean preoperative and postoperative PROMs were as following: PROMIS-Depression 50.3+/-4.2 and 45.6+/-9.8, PROMIS-Physical Function 39.0+/-3.4 and 45.0+/-7.8, SF-36 total score 55.8+/-15.3 and 73.2+/-20.0, SMFA-Function 29.0+/-13.5 and 15.9+/-5.4, VAS 15.8+/-24.8 and 3.1+/-10.1, and AOFAS hindfoot-ankle 46.3+/-16.5 and 81.1+/-16.3 (Table 1). Radiographic lucency at the bone- implant interface was noted in 33 (18.5%) TAAs at final follow-up; 20 (11.2%) were progressive. Lucency was almost exclusive to the tibial component. Implant survivorship was 99.6% [98.9-100.0] at 1-year and 93.3% [88.7-98.2] at the 5-year mark (Table 2, Figure 1). We identified suboptimal bone preparation, initial component alignment and/or component position in all 11 implant failures (Table 3). Conclusion: At early-to-intermediate followup, we observed favorable clinical outcomes, radiographic results and implant survivorship for the fixed-bearing Vantage TAA, especially with optimal bone preparation and component position. Tibial component lucency remains a concern and warrants further investigation. Suboptimal bone preparation, initial component alignment and/or component position was observed in all implant failures.