Abstract
Introduction
As the demand for primary total knee arthroplasty (TKA) has been on the rise, so will be the demand for revision knee surgery. Nevertheless, our knowledge on the modes of failure and factors associated with failure of knee revision surgery is considerably lower to that known for primary TKA. To date, this has been mostly based on case series within the literature. Therefore, the aim of this study was to evaluate the survivorship of revision TKA and determine the reasons of failure.
Methods
A retrospective study was conducted with prior approval of the institutional audit department. This involved evaluation of existing clinical records and radiographs of patients who underwent revision knee surgery at our institution between 2003 and 2015. Re-revision was identified as the third or further procedure on the knee in which at least one prosthetic component was inserted or changed.
Results
95 patients were identified who had re-revision knee replacement. Of these, there were 46 men (48%) and 49 women (52%) with an average age of 65 yrs. Infection was the main cause of failure (35.8%) followed by aseptic loosening (27.4%) and extensor mechanism problems leading to reduced range of motion (7.4%). Other causes included MCL Laxity (3.2%), oversized implants (3.2%) and fracture of the cement mantle (1.1%). The mean survivorship of revision knee replacements in our cohort was 31 months (Range between 1 – 119 months).
Conclusion
The survival of knee re-revision implants is considerably different from primary TKA implants. The results of our study provide an improved understanding of the modes of failure of re-revision knee replacements, enabling orthopaedic surgeons the opportunity to better understand the current problems associated with revision knee surgery and the potential to improve our outcomes by tackling these issues.