[Dissociation of a modular acetabular component in an uncemented total hip prosthesis. Effect of the modular design and anti-luxation rim. A case report].

We report a case of dissociation between polyethylene and metal-backing of the acetabular component of a total hip prosthesis after reduction of a late dislocation. We refer to advantages and disadvantages of an elevated-rim acetabular liner in total hip arthroplasty. The position of the metallic markers of the polyethylene and/or excentric situation of the neck-head complex from the metal-back allowed us to diagnose it. An appropriate surgical technique avoiding the joint laxity, firm assembly of the modular components when they are implanted, gentle reduction of an eventual dislocation and fluoroscopic control, are factors which can avoid this rare complication.