Abstract
Metal-on-metal hip resurfacing arthroplasty has been reintroduced as an alternative to total hip replacement. Uncemented acetabular fixation is now the gold standard for this procedure. However, uncemented femoral component fixation is less common. We thus report our preliminary results of an uncemented, hydroxyapatite-coated femoral implant at resurfacing arthroplasty. Between June 2001 and July 2002 we undertook 70 uncemented resurfacings in 66 patients. The survival rate of the femoral implants after a minimum of two years’ follow-up was 98.6%. The mean Harris hip scores for pain and function pre-operatively were 12.0 (maximum possible score 44) and 28.3 (maximum possible score 47) respectively. Postoperatively, at final follow-up, these scores were 39.25 and 43.07 respectively (Z= −6.94, p< 0.0001 for function and Z= −7.19, p< 0.0001 for pain). There have been no femoral fractures, aseptic loosening or radiolucencies around the stem. Thinning of the femoral neck at the inferomedial cup-neck rim has been a frequent radiological finding but with no clinical implications so far. The cup-neck ratio immediately after surgery was a mean of 1.05 while at last follow-up was 1.1 and this difference was statistically significant (Z= −4.14, p< 0.0001). Increased height (p=0.02) seemed to protect patients against neck thinning, whereas increased weight (p=0.06) seemed to favour it. Our preliminary results with a hydroxyapatite-coated femoral implant in metal-on-metal hip resurfacing have been promising with excellent survival rates and clinical outcomes. Longer follow-up studies are needed, particularly to interpret the clinical significance of neck thinning
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
