Secondary Procedures in Third Generation Total Ankle Arthroplasties

Abstract

Category: Ankle Arthritis Introduction/Purpose: As surgeons have become more comfortable with performing more complex total ankle replacements (TAR) with larger amounts of deformity, it is unclear whether or not to address additional pathology at the time of surgery. Currently, we address all foot and ankle pathology at time of the index arthroplasty. It is unclear however, how often and for what reasons secondary surgery is performed after TAR. We hypothesize that there were no differences in the type or rate of secondary surgeries performed. Methods: We identified a consecutive series of 761 primary TARs performed between January 1998 and December 2014. We identified patients who required a secondary surgery to treat foot and ankle pathology following a STAR, INBONE I/II, or Salto- Talaris. We then analyzed if there were differences between the implants in terms of time to secondary surgery or types of procedures performed. Results: 193 patients (25.3%) required a secondary procedure with an average time to a secondary procedure of 24.5 months. The rate of second surgery in both the Salto (25/113, HR=0.64 with 95%CI=0.408-0.996; p=0.048) and STAR (81/333, HR=0.694 with 95%CI=0.507-0.949; p=0.022) is less when compared to the INBONE group (87/315). The STAR had a significantly longer time to secondary procedure (33.8 months) versus a Salto-Talaris (12.8 months) or an INBONE (19.2 months, p=001). The number of secondary procedures (p< .001), polyethylene exchanges (p< .001), cyst grafting (p=.036) were similar in INBONE and STAR, but significantly more than the Salto. The INBONE prosthesis had a significantly higher talar component failure rate (p=.038), but similar rate of subtalar, ankle, and TTC fusion. Conclusion: Knowledge of the rates and types of secondary surgeries is useful information on the natural history of third generation ankle implants. While there are differences in the rate of failure or revisions between implants, no implant has proven superior to one another.