Reproducibility of the minimally invasive approach in unicompartimental knee replacement: 5-year follow-up of Oxford Phase III prosthesis

The Oxford III unicompartmental knee replacement (Biomet, UK) has proved to be efficacious in the treatment of the anteromedial arthritis of the knee. The aim of this study is to verify the reproducibility of the minimally invasive approach at an average follow-up of more than 5 years. We implanted 20 Oxford III (Biomet) prostheses with mobile bearing using antibiotic-loaded cement (Palamed G, Biomet). At follow-up the HSS score averaged 87.4 (range 50 -100), with 13 excellent, 3 good, 1 adequate and 3 poor. In the radiological analysis the geometrical parameters indicated in the surgical technique relative to this prosthesis were reproduced in all the implants. The average ROM reported is 133.85°. No cases of infection, nor more serious complications were found; in the 3 patients (15%) with unsatisfactory outcome this was due to the progression of the arthritis in the lateral compartment at the last 5 years follow-up.