The Revolution and Unanswered Questions

Abstract

Commentary With the relatively recent publication of the long-term results of total ankle replacement1, as well as the efficacy of this procedure compared with ankle arthrodesis2, total ankle replacement is rapidly becoming a viable option in the treatment of degenerative disorders of the ankle. As more orthopaedic surgeons continue to push the boundaries and as more residencies and fellowships are training surgeons in this procedure, there will obviously be an increase in the number of total ankle replacements performed each year. Couple that with the aging population and perceived quality-of-life issues, and I believe that we are on the cusp of a revolution in the treatment of such diseases. Although there will always be a role for ankle arthrodesis, I believe that total ankle replacement, much like total knee and total hip replacement, will become the standard of care. However, along with such advancement there will be new questions that need to be addressed regarding indications for total ankle replacement (limitations involving deformity, age, and weight) and revision options. The article by Hintermann et al. addresses the question regarding revision surgery, and it is an important article as the primary implants will have a limited life span and there will be a need for viable revision solutions even with use of the strictest indications. The strengths and weaknesses of this article are closely related. The most obvious weakness, from my perspective, is that it represents merely another case series study performed by a single surgeon with use of his prosthesis design, which is currently not available for use in the United States. Will these results be reproducible, and how can we interpret this information regarding an implant that is currently not available for use in the United States? In my opinion, however, this study goes beyond outcome reporting. It is a starting point from which to begin to answer revision-related questions. The authors present a classification system for evaluating failure and bone loss defects that will be useful for further publications and discussions regarding the patterns of failure. The authors also go further by defining principles for revision surgery that are potentially general in nature, useful for a range of similar primary implant designs. The failures of the primary ankle replacements were not limited to a single implant design, and the authors applied their concepts across a broad spectrum of failures with good intermediate-term results. The results would, in fact, have been useful even if the revision outcomes had been poor. Surgeons will also be able to use the information in discussing the available options and outcomes with their patients when total ankle replacements fail. Although I do not believe that this will become a landmark article, I do believe that it is the type of article that is needed, especially as we begin to try to answer the questions that will be posed as more total ankle replacement procedures are performed. Obviously, other studies will need to be performed, including direct comparisons of ankle arthrodesis with revision, to allow the surgeon to make decisions regarding the best option for patients. Even other surgeons’ experiences will be useful as we strive to answer the question of what to do about implant failure, other than tell our patients that we’ll cross that bridge later. This study is a necessary starting point that provides a guideline for revision surgery and will advance our understanding of the use of total ankle replacement. Although the outcome results presented in this article may only be directly applicable to the HINTEGRA implant, the overall concepts are beneficial to our understanding of the future treatment options for failed total ankle replacements.