Between 1976 and 1980, 81 knees in 59 patients 75 years of age or older, underwent primary total knee arthroplasty with a cemented, condylar femoral component and a cemented, moderately conforming, all polyethylene tibial component. All patients were followed up until death, revision surgery, or for a minimum of 10 years. Mean clinical followup was 8.1 years for the entire group and 14.6 years for those patients still alive. At final followup one patient (one knee) required revision surgery (for medial instability), and one patient (one knee) had marked pain but no radiographic evidence of loosening. No patients required revision surgery for aseptic loosening and no patients had symptomatic aseptic loosening at last followup. The mean Knee Society knee and function scores were 78 and 64 points, respectively at last followup. The mean postoperative range of motion was 101°. The Kaplan-Meier survival of the index total knee arthroplasty at 14 years was 100% with symptomatic aseptic loosening as the end point; and 98% with revision for any cause as the end point. Cemented all polyethylene tibial components with a moderately conforming tibio-femoral articulation implanted in patients older than 75 years of age showed a high rate of survivorship without the need for revision surgery and without symptomatic loosening.
From the Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota.