BMD better preserved with resurfacing arthroplasty than THA

BMD better preserved with resurfacing arthroplasty than THA

Smolders J. J Arthroplasty. 2012. doi:10.1016/j.arth.2012.08.025.

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  Pressfit resurfacing hip arthroplasty was found to better preserve periacetabular bone mineral density (BMD) than conventional total hip arthroplasty (THA) in this randomized controlled trial that included 71 patients.December 28, 2012

"We focused on periprosthetic BMD changes in the acetabulum after a bone-preserving RHA (resurfacing hip arthroplasty) and the potential pitfall of gradual bone resorption due [to] the effects of an acetabular cup implantation," José M.H. Smolders, MD, and colleagues stated in the study.

"We found that after placement of a thick press-fit resurfacing cup the supposed decrease of BMD seems not to be as critical as indicated in some finite element studies. We can conclude that, on the short term, an RHA press-fit cup does not lead to more decline in periprosthetic BMD as compared to an established conventional threaded titanium acetabular component,” Smolder and colleagues, of The Netherlands, wrote in the study.

Seventy-one patients were randomly assigned either to an RHA press-fit cobalt-chromium cup (Conserve Plus; Wright Medical Technology, Arlington, Tenn., USA) and a cemented femoral component or THA with a tapered uncemented Zweymüller stem (Zimmer; Warsaw, Ind., USA), a threaded titanium cup and a polyethylene-metal-inlay insert, according to the abstract.

The researchers studied five periacetabular regions of interests in both groups and found the RHA patients had better preserved BMD than THA patients. They noted, however, that these results are only through 24-months follow-up and more research is needed.