Influence of stem type on material loss at the metal-on-metal pinnacle taper junction

Proc Inst Mech Eng H. 2015 Jan;229(1):91-7. doi: 10.1177/0954411914567931.

Abstract

The clinical importance of material loss at the head-stem junction is unknown. Comparison of retrievals with different stem types can provide the opportunity to understand the importance of the taper junction. This was a case-control study involving 20 retrieved 36 mm metal-on-metal Pinnacle (DePuy) hips that were paired with either a Corail (n = 10) or S-ROM (n = 10) stem. The median head taper material loss rate for the Corail group was 0.238 (0.0002-2.178) mm(3)/year and was significantly greater than the S-ROM group (p = 0.042), which had a median material loss rate of 0.132 (0.015-0.518) mm(3)/year. The only significant difference between the groups was the stem taper roughness and length: this was rougher and shorter for the Corails. Long and smooth stem taper designs are preferred when used in conjunction with metal heads.

Keywords: Wear analysis/testing; biomedical devices; hip prostheses; medical biomaterials; orthopaedic tribology.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Equipment Failure Analysis
  • Female
  • Friction
  • Hip Prosthesis*
  • Humans
  • Metal-on-Metal Joint Prostheses*
  • Metals / chemistry*
  • Middle Aged
  • Particle Size
  • Prosthesis Design
  • Surface Properties

Substances

  • Metals