In 11 total hip replacement operations performed on nine patients with acetabular protrusion, the deficient acetabulum was reinforced with a bone graft from the femoral head in ten operations and in one from the greater trochanter and the femoral medullary canal. Acetabular meshes were used in two operations and a fine wire mesh in one. At follow-up, averaging 18 (8-28) months postoperatively, a solid bone socket for the acetabular component had formed in all hips without evidence of loosening or infection.