Stress fractures after total knee arthroplasty.

Fifteen patients sustained fractures of the tibia after geometric and polycentric total knee arthroplasty. The mean follow-up after arthroplasty was 45.1 months. The chief causes for the stress fractures were axial malalignment and improper component orientation. All fifteen patients experienced loosening of the prosthesis and required revision arthroplasty for a satisfactory result. Revision at the time of diagnosis of the fracture did not adversely affect fracture healing.