Second-generation locking mechanisms and ethylene oxide sterilization reduce tibial insert backside damage in total knee arthroplasty

J Arthroplasty. 2011 Jun;26(4):523-30. doi: 10.1016/j.arth.2010.04.024. Epub 2010 Jun 11.


This study evaluated the effects of polyethylene quality and locking mechanism on damage to the nonarticulating (backside) surface of retrieved tibial inserts in total knee arthroplasty. Inserts with peripheral capture (PC) locking mechanisms and ethylene oxide (EtO)-sterilized polyethylene were hypothesized to prevent major backside damage. A total of 156 inserts were sorted by locking mechanism and sterilization method and analyzed by damage scoring methods. Ninety-seven specimens exhibited burnishing. Significant positive linear correlations were observed between damage score and age in vivo for all combinations, but damage occurred at a significantly lower rate for second-generation PC implants with EtO sterilization. Most specimens in this group were undamaged (46/72), with others exhibiting only burnishing. Sex, body mass index, and weight did not influence backside damage.

Publication types

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

MeSH terms

  • Age Factors
  • Arthroplasty, Replacement, Knee / instrumentation*
  • Body Mass Index
  • Equipment Failure
  • Equipment Failure Analysis
  • Ethylene Oxide*
  • Female
  • Gamma Rays*
  • Humans
  • Knee Prosthesis*
  • Linear Models
  • Male
  • Polyethylene
  • Prosthesis Design*
  • Sex Factors
  • Sterilization / methods*
  • Surface Properties
  • Tibia / surgery*


  • Polyethylene
  • Ethylene Oxide