The St. Leger total knee replacement--a 7-year clinical assessment and survivorship analysis.

The St. Leger total knee replacement was developed with the aim of producing an affordable prosthesis which contained the best known features of current designs and also allowed ease of instrumentation. We present the medium term clinical and radiographic outcome and survivorship of the prosthesis. From 1992 to August 1994, 150 St. Leger total knee replacements were performed on 53 male and 72 female patients. Mean age was 67 (Range: 40-86). Sixty-nine percent of operations were for osteoarthritis and 30% for rheumatoid arthritis. Patients were reviewed at 1, 4 and 7 years postoperatively by an independent assessor. One hundred and twenty-three patients were assessed at 4 years and 83 patients at 7 years. The American Knee Association Scores revealed 84% excellent or good, 9% fair, and 7% poor results at 7 years. No patients complained of severe pain, 90% had mild or no pain, 10% had moderate pain. Eighty nine percent of patients were satisfied with their outcome. There were five complications requiring revision: infection (2), loosening (1), valgus instability (1) and knee stiffness (1). Survivorship analysis revealed 95% (95% CI +/-7.2%) survival at 7 years. Total knee replacement using the St. Leger knee prosthesis has comparable results to other condylar knee systems that cost almost twice the price.