Dissociation of the S-ROM metal-backed polyethylene acetabular liner--a case report and literature review.

The authors report a case of early failure of a total hip arthroplasty with dissociation of the polyethylene liner of an S-ROM Oblong Cup*, which presented as a dislocation. Initial closed reduction of the dislocation was not possible. Open exploration of the hip revealed that the modular Poly Dial* polyethylene acetabular liner had become dislodged from the acetabular cup. The liner was revised and a stable reduction of the hip was achieved. To our knowledge, no previous case of dissociation of the polyethylene liner from the S-ROM Oblong acetabular component has been reported. A review of the literature with other relevant cases is presented.