Abstract
The Birmingham Hip Resurfacing (BHR) has been used in the younger more active patient for the treatment of advanced osteoarthritis. Long-term follow-up of the BHR is limited. The Australian national joint replacement registry shows that failure rates vary greatly, depending on implant types. 77 consecutive BHR procedures with a minimum ten year follow-up are reported.
There were 70 patients (44 males and 26 females) with an average operation age of 57.4 years (SD ±12.6). All patients were evaluated, including the “learning curve” patients. The mean follow-up period was 11.42 years (SD ±0.50). The arthroplasties were performed between April 1999 and December 2000 by one surgeon, with a standardised patient selection set of criteria. Data and outcome measurements were collected prospectively and analysed retrospectively. We evaluated Harris Hip Scores, Short Form-36 (SF-36v2) Scores, Tegner Activity Score Scores and McMaster Universities Osteoarthritis Index Scores (WOMAC) comparatively at preoperative, six month and yearly intervals
In 8 patients (10 procedures) the implant was in situ at the time of death. Revision was carried out in 6 hips (7.8%) at a mean time period of 2.5 years (0–10) post-operatively. Failure was due to femoral neck fracture in four patients, acetabular loosening in one and avascular necrosis of the femoral head, leading to loosening, in one patient. Kaplan-Meier analysis showed survivorship of 92.2% to 10 years. The mean Harris Hip scores (paired t-test, p<0.05) improved significantly from 59.7 preoperatively to 80.1 at ten years. The mean SF-36v2 physical scores (paired t-test, p<0.05) improved significantly from 35.09 preoperatively to 47.83 at ten years. WOMAC scores (paired t-test, p<0.05) improved significantly from 54.61 preoperatively to 85.89 at ten years.
The BHR prosthesis, in this series, has been shown to be effective, reliable, and durable in this group of highly active, relatively young patients. Problems with metallic debris, sensitivity reactions, and osteolysis have not been seen. However, we believe that with better selection criteria, improved understanding of component positioning and surgical techniques, results can be improved.
