Total Hip Replacement (THR) in proximal, posterior iliac dislocation of the hip often represents a problematic issue. Reviewing their selected cases (70 patients between 3700 THR from 1986 to 2001), authors focalized some key points for this demanding surgery. The most important steps are acetabular positioning, implant decisioning and surgical approach (exposure and release).

Acetabular cup positioning. The natural site (Paleoacetabulum), the ideal place to restore biomechanical and dynamic properties of the joint, many times gives few chances to achieve primary stability. So one site, at least the nearest possible to the natural site must be reached. A CT or MRI study is necessary to assess preoperative planning for cup positioning. We used two different cups, the Zweymuller and the Wagner cup, with good primary stability. A Conus stem (Wagner) or an Alloclassic stem (in less displastic femoral shape) was used.

We always performed this surgery as a one step procedure. No preventing traction or release surgery was performed. An anatomic and wide (medial and lateral) exposure of the joint must be performed. We used the Smith-Petersen approach modified by Wagner. A meticulous periarticular release of soft tissue was performed. In same cases a shortening femoral osteotomy was performed to allow refractory reduction. Possible complications are discussed. Good clinical outcomes at more than ten years are shown.