Does Increased Coefficient of Friction of Highly Porous Metal Increase Initial Stability at the Acetabular Interface?

Journal Article (Journal Article)

BACKGROUND: Highly porous metal acetabular components illustrate a decreased rate of aseptic loosening in short-term follow-up compared with previous registry data. This study compared the effect of component surface roughness at the bone-implant interface and the quality of the bone on initial pressfit stability. The null hypothesis is that a standard porous coated acetabular cup would show no difference in initial stability as compared with a highly porous acetabular cup when subjected to a bending moment. Second, would bone mineral density (BMD) be a significant variable under these test conditions. METHODS: In a cadaveric model, acetabular cup micromotion was measured during a 1-time cantilever bending moment applied to 2 generations of pressfit acetabular components. BMD data were also obtained from the femoral necks available for associated specimen. RESULTS: The mean bending moment at 150 μm was not found to be significantly different for Gription (24.6 ± 14.0 N m) cups vs Porocoat (25 ± 10.2 N m; P > .84). The peak bending moment tolerated by Gription cups (33.9 ± 20.3 N m) was not found to be significantly different from Porocoat (33.5 ± 12.2 N m; P > .92). No correlation between BMD and bending moment at 150 μm of displacement could be identified. CONCLUSION: The coefficient of friction provided by highly porous metal acetabular shells used in this study did not provide better resistance to migration under bending load when compared with a standard porous coated component.

Full Text

Duke Authors

Cited Authors

  • Goldman, AH; Armstrong, LC; Owen, JR; Wayne, JS; Jiranek, WA

Published Date

  • March 2016

Published In

Volume / Issue

  • 31 / 3

Start / End Page

  • 721 - 726

PubMed ID

  • 26639983

Electronic International Standard Serial Number (EISSN)

  • 1532-8406

Digital Object Identifier (DOI)

  • 10.1016/j.arth.2015.10.012


  • eng

Conference Location

  • United States