Chondromalacia and patellofemoral osteoarthritis are common diseases that cause pain and disablement of the knee. Conservative therapy is not always effective. Since 1983 we have used isolated polyethylene patellar prosthesis for patella resurfacing of 19 patients with patellofemoral osteoarthritis. After an average of 44. 9 months follow-up

we found the treatment was not as satisfactory as earlier trials. The main reason is the wide erosion of femoral condyle caused by the polyethylene patella. To overcome this shortness

we designed a new type of patellofemoral prosthesis which is named Y-L-Q. From January . 1991 to November. 1 993

we used this prosthesis to treat 16 knees of 13 patients with patellofemoral osteoarthritis. Most of those patients improved both symptomatically and functionally. The good to excellent results rate was 87. 5% （1 4/16 knees） at the time of an average 16 months follow-up. The early results of our experience with patellofemoral resurfacing are encouraging. And extended follow-ups are in progress.