Abstract
Aims: Resurfacing arthroplasty of the hip is increasing in popularity. Recently concerns have been raised about resorbtion of the femoral neck after hip resurfacing, which may increase the risk of femoral neck fracture. We conducted a study to assess the degree of femoral neck resorbtion after using a cemented femoral component at hip resurfacing arthroplasty and to compare this with an uncemented femoral component.
Patients and Methods: We included 130 patients who had undergone a hip resurfacing arthroplasty in our study. Our uncemented group included 70 consecutive patients who had received an uncemented Cormet hip resurfacing arthroplasty (Corin, Cirencester, UK). Our cemented group included 60 patients who had received a cemented Birmingham hip resurfacing arthroplasty (Smith and Nephew, Cambridge, UK). All patients were regularly followed up for a minimum of two years. Clinical outcome was assessed using Harris hip scores. Femoral neck resorbtion was assessed by measuring the cup-neck ratio on post-operative radiographs by two independent observers.
Results: The mean age of the patients was 50.7 years for the cemented resurfacing group and 51.5 years for the uncemented resurfacing group. No difference was found in Harris hip scores between the two groups at any of the follow-up periods. The overall survival rate at two years was 100% for the cemented group and 98.6% for the uncemented group. There was however, a significant increase in femoral neck resorbtion for the cemented resurfacing group compared to the uncemented resurfacing group (median cup-neck ratio 1.11 vs. 1.04), p< 0.0001
Conclusion: We found a significant increase in femoral neck resorbtion with the use of a cemented femoral component at hip resurfacing arthroplasty compared with an uncemented femoral component. This may increase the risk of femoral neck fracture and could affect the long-term outcome if a cemented femoral component is used.
Editoral Secretary Mr Peter Howard. Correspondence should be addressed to BHS at the Royal College of Surgeons, 35 - 43 Lincoln’s Inn Fields, London WC2A 3PN.
