Long-term results of the total condylar knee arthroplasty. A 15-year survivorship study

This study reports the 15-year survivorship of 112 consecutive Total Condylar knee arthroplasties that have been followed since 1974. Two endpoints were chosen for survivorship: (1) Revision attributable to septic or aseptic loosening or malalignment. (2) Revision or roentgenographic evidence of component loosening. Life table analysis reveals a 94.1% clinical survivorship at 15 years, with an 90.9% survivorship when roentgenographic failures are included. There were five revisions: one for infection, one for instability, and three for tibial loosening. In addition, two tibiae and one patella were considered roentgenographically loose, but were not symptomatic. As of May 1992, 34 patients with 48 knees are known deceased, 15 knees are lost to follow-up evaluation, and 49 knees are available for clinical evaluation. Follow-up data was available on 62 knees for greater than 11 years. Ninety-two percent had good or excellent results, with 1.6% fair and 6.5% poor. Average range of motion was 99 degrees. The average Hospital for Special Surgery knee score was 85. Roentgenographic study revealed lucencies around 72% of tibiae, but only two components were loose. There was a correlation between body weight and the presence of radiolucencies, and patients who weighed more than 80 kg had the lowest survivorship at 15 years: 89.2% clinical survival and 70.6% clinical plus roentgenographic survival. Total Condylar knee arthroplasty has a 94.6% clinical survival at 15 years, with predictably good clinical results.