Long-term results for the McKeever patellar resurfacing prosthesis used as a salvage procedure for severe chondromalacia patellae.

From July 1972 until September 1985, 28 patients with a mean age of 36 years who had advanced arthritis of the patella were treated with a resurfacing arthroplasty using the McKeever prosthesis. The opposing articular surface of the femur appeared normal in 19 patients. The 28 patients had had a total of 50 previous operations on the patella (average, 1.8 operations per patient). These included 15 arthroscopic or open debridements, 14 lateral releases, six Maquet tibial tubercle elevations, six open patellar ligament transpositions, and seven open procedures for reduction and fixation of patellar fractures. Every case was observed postoperatively from a minimum of four years to a maximum of 16 years (mean, 8.1 years). Results were evaluated according to a patellar rating scale at five and eight years postoperatively. Seventeen of 24 were rated good or excellent at five years. Of the three poor results at five years, two were attributed to tricompartmental osteoarthrosis and were revised to total knee arthroplasties. There were no significant complications in the series. No patients had postoperative patellar instability or prosthetic loosening. Prolonged physical therapy rehabilitation (mean, 4.6 months) was necessary for patients to regain maximal ranges of motion, muscle strength, and endurance.