Surface damage after multiple dislocations of a 38-mm-diameter, metal-on-metal hip prosthesis

J Arthroplasty. 2008 Oct;23(7):1090-6. doi: 10.1016/j.arth.2007.09.007. Epub 2008 Mar 14.

Abstract

We present, for the first time, a detailed damage assessment of a large-diameter metal-on-metal (L-MOM) hip prosthesis to show the extent of surface damage that can occur in a patient after multiple dislocations. The patient was a man (51 years old) who dislocated 8 times and was finally revised at 27 months. Radiographically, the cup was malpositioned with 65 degrees lateral opening and 15 degrees retroversion. The retrieved cup was a 1-piece, 38-mm Co-Cr-Mo (M2a; Biomet, Warsaw, Ind) with a titanium-alloy backing. The retrieved components demonstrated all known modes of wear, including a polished wear scar, multidirectional scratching, "stripe" wear, surface contamination of titanium-alloy, front face wear, and backside wear. The clinical significance is that cup positioning remains critical regardless of whether a large diameter head is used or not.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arthroplasty, Replacement, Hip / adverse effects*
  • Hip Dislocation / etiology
  • Hip Dislocation / surgery*
  • Hip Prosthesis / adverse effects*
  • Humans
  • Male
  • Middle Aged
  • Prosthesis Failure*
  • Reoperation