Abstract
Due to the success, quantified by both clinical improvement and durability, the number of TKA procedures performed annually has steadily increased since its introduction and it is predicted that approximately 3 million knee arthroplasties will be performed in 2030. Part of this exponential growth is due to indication expansion and TKA is now often performed for younger, more active and heavier patients that historically would have been denied the procedure. Combined with an aging population, often afflicted with comorbidities, it is not surprising that the number of TKA revisions performed annually is also increasing. TKA failure, with subsequent revision surgery, is a costly problem often associated with substantial morbidity. In order to reduce the incidence of TKA failure, it is critical that we expand our knowledge of the issue by asking the question, why are TKAs failing today? Due to a demographically evolving arthroplasty population, the introduction of the new surgical techniques and the routine addition to the market of next generation implants, it is likely that the mechanisms for TKA failure will change over time. It is also possible that there may be regional and even institutional variance when the reasons for TKA failure are investigated. Therefore, it is critical that this question concerning failure mechanisms be repeatedly studied and examined by various study designs in multiple clinical settings.
This lecture will focus on several key aspects of TKA failure: Early (less than 2 to 5 years) vs. late failure; Historically, why did TKAs fail and what has been done to decrease certain failure modes; Why are TKAs failing today?
Only with a comprehensive understanding of TKA failure mechanisms will we be able to properly address this problem and focus our efforts and resources on meaningful solutions. Even incremental improvements that only modestly decrease TKA failure incidence should provide our healthcare system with enormous savings and more importantly, greatly decrease patient morbidity.
