Survivorship analysis of cementless meniscal bearing total knee arthroplasty

Four hundred seventy-three consecutive cementless cruciate retaining meniscal bearing primary total knee replacements were done on 375 patients from May 1985 to February 1991. These were observed for a 10-year period (average, 5 years). Seventeen (3.6%) required change of components because of mechanical failure. There were 12 polyethylene fractures or dislocations. There were 5 tibial subluxations secondary to ligamentous instability occurring at an average of 21 months postoperatively. There were 2 component loosenings secondary to bone graft resorption (1 femoral, 1 tibial). There were 5 infections (4 Staphylococcus aureus, 1 Pseudomonas). Significantly, with the exception of the 2 knees with bone graft resorption, there was no component (femoral, tibial, or patellar) loosening. Kaplan-Meier survival estimates, using as an endpoint of revision surgery for any mechanical reason (polyethylene breakage, polyethylene dislocation, or ligamentous instability), showed a survivorship of 94.6% at the 8-year interval. Survivorship related to mechanical loosening of fixation of any component at the 8-year interval was 99%.