Double acetabular wall--a misleading point for hip arthroplasty: an anatomical, radiological, clinical study.

Purpose: Despite the great attention focused on cup positioning in primary total hip arthroplasty (PTHA), it is surprising to find so few studies that have dealt with cup placement. A common thwarting problem for correct cup placement during PTHA is the existence of osteophytes, which obscure the anatomical landmarks. In this study we aimed to evaluate the morphology of acetabular osteophyte formation in patients with osteoarthritis.

Method: We evaluated 276 patients with hip complaints, using plain X-rays and CT scans.

Results: Of these patients, 57 underwent surgery. We developed a staging system for central osteophytes in hip osteoarthritis based on the radiographic and anatomical findings of our patients.

Conclusion: We recommend routine use of CT scans for patients scheduled for PTHA in order to assess the stage of osteophyte before surgery and, thus, reduce the risk of failure resulting from the interrupted acetabular landmarks.