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Surface replacement of the hip: a late revision.

An 86-year-old lady, who 23 years previously had had a surface replacement of her right hip to relieve pain from osteoarthritis, experienced a sudden pain in her right groin, radiating down to her ankle, when she rose from her chair. She was then unable to bear weight. She recounted having had some groin discomfort for the previous 4 months, but had been pain-free and independently mobile without aids for the antecedent 22 years. 
 
Upon examination, her right leg was found to be shortened, with no active movement at the hip; she had pain on the slightest movement. Her distal neurovasculature was intact. Radiographs (Fig. 1) showed that the acetabular component had failed and displaced. The following day, she underwent hip revision to a conventional cemented Exeter arthroplasty by a posterior approach (Fig. 2). She made excellent progress and was discharged 6 days later. 
 
 
 
FIG 1. Radiograph showing failure and displacement of the acetabular component of a total-hip articular replacement by internal eccentric shells (THARIES) 23 years old. 
 
 
 
 
 
FIG 2. The resected components and femoral neck of the THARIES, 23 years after the resurfacing procedure.