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.