A 94.5% Ten-Year Survival Is Reported for Birmingham Hip Metal-on-Metal Resurfacings

Newswise — A study by G. Coulter, D. A. Young, R. E. Dalziel, and A. J. Shimmin, published this month in The Journal of Bone & Joint Surgery (British Volume) reports on the findings of an independent review of 230 consecutive Birmingham hip resurfacings (BHRs) in 213 patients (230 hips) at a mean follow-up of 10.4 years (9.6 to 11.7).

A total of 11 hips underwent revision; six patients (six hips) died from unrelated causes; and 13 patients (16 hips) were lost to follow-up. The survival rate for the whole cohort was 94.5% (95% confidence interval (CI) 90.1 to 96.9).

The survival rate in women was 89.1% (95% CI 79.2 to 94.4) and in men was 97.5% (95% CI 92.4 to 99.2). Women were 1.4 times more likely to suffer failure than men.

For each millimetre increase in component size there was a 19% lower chance of a failure. The mean Oxford hip score was 45.0 (median 47.0, 28 to 48); mean University of California, Los Angeles activity score was 7.4 (median 8.0, 3 to 9); mean patient satisfaction score was 1.4 (median 1.0, 0 to 9).

A total of eight hips had lysis in the femoral neck and two hips had acetabular lysis. One hip had progressive radiological changes around the peg of the femoral component. There was no evidence of progressive neck narrowing between five and ten years.

The results confirm that BHR provides good functional outcome and durability for men, at a mean follow-up of ten years. The authors suggest that 'we are now reluctant to undertake hip resurfacing in women with this implant'.

Read the full paper: http://www.jbjs.boneandjoint.org.uk/content/94-B/3/315.full