Abstract
Introduction and aim
One of the suggested advantages of hip resurfacing arthroplasty is that it offers the possibility of straightforward revision. As the femoral canal is not violated during the resurfacing procedure, it is postulated that the outcome of revision surgery should be equivalent to that of a primary hip arthroplasty. The purpose of this study was to investigate whether revision was as straightforward and as successful as has been suggested.
Method
14 patients underwent revision surgery due to the failure of the femoral component of their Birmingham hip resurfacing. The femoral component was revised to a cemented Zimmer CPT stem, with a large modular metal head (MMT). The acetabular component was found to be well fixed and was left in situ. Radiographs were studied to review any change in offset. These patients were matched with a group who had undergone a hybrid total hip arthroplasty as a primary procedure, using the same bearing. The Oxford and Harris Hip scores were used to measure outcome.
Results
In the revision group, there were 10 males and 4 females. The mean age was 56 (48-68). The mean time to revision was 11.6 months. The reasons for revisions were: 9 femoral neck fractures, 4 femoral neck resorptions and 1 femoral component migration. Post-revision Oxford score =18 (12-25), HHS=92 (85.5-97.4). Post-primary Oxford score =18 (12-40), HHS=94.2 (86-97.4). Comparison of the post-op radiographs demonstrated that offset was improved following revision. The mean follow-up was 2 years, there were no major complications, operative time and blood loss were not significantly different.
Discussion
Our results show that revision of the failed femoral component gives excellent results. The outcome was not significantly different to the primary THA group. Femoral offset was restored in total hip replacement compared to resurfacing.