The Oxford II medial unicompartmental knee replacement. A minimum 10-year follow-up study.

Background. The first clinical results from unicondylar knee arthroplasty (UKA), which was introduced in the early seventies, were non-conclusive. The development and modernization of unicompartmental implants (mobile bearing models, such as Oxford II), and also stricter qualification criteria for UKA brought about significant improvement in long term outcome. The aim of our study was to assess the long-term outcome of UKA using Oxford II implants, and also to verify the inclusion criteria. Material and methods. The authors present an analysis of long-term outcome in unicompartmental knee arthroplasty in 42 patients, qualified for treatment according to the criteria of Kozin and Scott, and also the designers of the implant. The follow-up assessment was performed a minimum of 10 years after surgery (11.2 years average). Results. The results were assessed using the 100-point HSS scale. Excellent results were achieved in 10 cases, good results in 22 cases, fair results in 6 cases, and poor results in 4 cases. The implant survival rate was 86%. There were some complications related to surgical error or lack of strict compliance with the qualification criteria. Conclusion. UKA late results are comparable to those achieved in TKA, given proper qualification. Also, this procedure can be considered as a definitive solution in older patients.