Abstract
We report on metallosis in bilateral knees which occurred after total knee arthroplasties with cementless Press Fit Condylar total knee prostheses. Our operative findings indicate that the metallosis was due to lateral subluxation of the patellar component and polyethylene wear of the metal-backed patellar component; furthermore, in one knee, it was due to breakage of the polyethylene caused by concentrated contact pressure on the large patellar implant, which gave rise to a large moment arm. Body weight and range of motion played important roles in failure of both knee prostheses. We concluded that, in the case of elderly and overweight Japanese patients, total knee arthroplasty places significant demands on the patellar component.
