Fig. 1
From: Total hip arthroplasty to treat acetabular protrusions secondary to rheumatoid arthritis
a Left hip exhibiting rheumatoid arthritis (RA) with an acetabular protrusion. The femoral head protruded inward over Nelaton’s line. The disease was of Sotello-Garza and Charnley type II. b Total hip arthroplasty (featuring placement of a porous tantalum acetabular cup; Zimmer) accompanied by acetabular reconstruction with autologous bone. An X-ray taken immediately after surgery revealed that the hip joint rotational center had returned to the normal location. The initial acetabular cup stability was good. c At the 5-year follow-up, an X-ray revealed complete bone graft healing, without bone resorption or acetabular loosening