Abstract
The purpose of this study was to evaluate the clinical outcome of a hydroxyapatite (HA)-coated tapered stem and to assess bone remodelling of the proximal femur using quantitative computed tomography osteodensitometry.
Fifty consecutive hips were managed with total hip replacement using the Cerafit Multicone H-A.C. stem with HA coating and the Cerafit Triradius-M press-fit cup (Ceraver Osteal, Paris, France). The mean follow-up was 3 years (range, 2.9 to 4 years). Current criteria were used for clinical and radiological assessment.
Forty-nine hips (98%) were clinically rated good or excellent. The mean preoperative Harris Hip Score was rated 57, and it has improved to 96 at the time of follow-up. The radiographs showed stable fixation by bone ingrowth in all hips. Fifteen patients (15 hips) were eligible for osteodensitometry. The mean decrease of the overall bone density (BD) in the metaphyseal portion of the femur 3 years after insertion of the stem was rated 14.21%, and the mean decrease of the cortical BD was rated 15.52%. The mean decrease of the overall BD in the diaphyseal portion of the femoral component was rated 10.00%, and the mean decrease of cortical BD was rated 7.76%. Little changes were observed underneath the tip of the stem.
The clinical and radiological outcomes of the tapered stem with HA coating at a mean follow-up of 3 years compares favourably with other reports. Results of osteodensitometry show less proximal femur BD loss in comparison to similar investigations performed using uncemented stems.
The abstracts were prepared by Jean-Claude Theis. Correspondence should be addressed to him at Department of Orthopaedic Surgery, Dunedin Hospital, Private Bag 1921, Dunedin, New Zealand.
