[Total hip arthroplasty with uncemented cup and femoral head autografts for coxarthrosis due to dysplasia].

OBJECTIVE: To evaluate the outcomes of total hip arthroplasty (THA) for coxarthrosis due to dysplasia with acetabular reconstruction of an uncemented cup in conjunction with a femoral head autograft.

METHODS: A retrospective study was made on 21 hips in 20 patients (18 female and 2 male; average age, 50 years) with developmental hip dysplasia treated by THA with use of an uncemented cup. The acetabular cup was placed at the level of the true acetabulum; all patients required autogenous femoral head grafts due to acetabular deficiency. The average coverage of the acetabular cup by the femoral head autograft was 31% (range, 10% to 45%). Eight hips had less than 25% cup coverage and 13 between 25% and 50%. The average follow-up period was 4.7 years (range, 1-8 years). All patients were evaluated with the use of a modified Harris hip score. Radiographic evaluations were made by preoperative and follow-up.

RESULTS: All autografts were seen to be united to host-bone. No collapse of the autograft and no hip had the evidence of loosening of component seen in all patients. According to the modified Harris hip score, the average hip score increased from 46 at preoperation to 89 at the final review. Preoperative leg-length discrepancy was greater than 2 cm seen in all except 1 patient with bilateral hip dysplasia. After surgery, only 2 of 20 patients still had a leg-length discrepancy greater than 1 cm. Three hips showed minor resorption in the lateral portion of the graft which was not supporting the cup. Three hips developed grade 1 Brooker heterotopic ossification and one had grade 2.

CONCLUSIONS: THA with an uncemented cup in conjunction with a femoral head autograft for coxarthrosis due to dysplasia could obtain favorable results. This method could provide reliable acetabular fixation and appeared to restore acetabular bone stock in patients with developmental hip dysplasia when the coverage of the cementless cup by the graft does not exceed 50%.