Abstract
Aim: To provide information on treatment outcomes for patients who received an acetabular component inserted with a polyethylene liner and to compare the results with those of patients who received the same acetabular component inserted with an alumina liner.
Methods Sixty consecutive patients (60 hips) with osteoarthrosis were allocated to two matched-pair groups. The patients were matched for age, gender, body-mass-index, level of activity, and bone stock. The first group of 30 hips (control group) received a total hip arthroplasty with a press-fit acetabular component, a polyethylene liner and an alumina femoral head. The second group of 30 hips (alumina group) was operated on using the same prosthesis, but an alumina liner was inserted instead of polyethylene.
Results: At a mean follow-up of five years (4.5 to 5.5 years) the mean Harris hip score was 94.1 points in the control group, and 92.7 points in the alumina group. No hip required revision, and there was no radiographic evidence of aseptic loosening.
Discussion: Modular acetabular components with alumina liners are currently used in total hip arthroplasty, but concerns have emerged regarding their high stiffness, which could cause impairment of stability, stress-shielding phenomena, and early loosening. In the present study, the acetabular components with an alumina liner functioned well overall and patient satisfaction was high at an average of five years postoperatively. Clinical and radiological results did not contrast with those achieved using the same prosthesis with a polyethylene liner.
The abstracts were prepared by Professor A. J. Thurston. Correspondence should be addressed to him at the Department of Surgery, Wellington School of Medicine, PO Box 7343, Wellington South, New Zealand
