Primary fit of the Lord cementless total hip : a geometric study in cadavers

Two Lord prostheses, bilaterally implanted in cadavers, were sectioned. The contact areas between bone and prosthesis were studied and measured using a specially developed reproducible method. Primary fixation of the femoral components appeared to be based principally on wedging of the prosthetic stem in the femoral shaft with a rather small contact surface. In both acetabuli the screw threads of the rings were only marginally in contact with the acetabular bone.