High stress conditions do not increase wear of thin highly crosslinked UHMWPE. Academic Article uri icon

Overview

abstract

  • Introduction of highly crosslinked polyethylene has increased interest in large femoral heads, because thin acetabular liners can be used while maintaining low wear rates and larger heads decrease the incidence of instability. However, crosslinking and subsequent thermal treatments can cause decreased mechanical properties that might obviate the reduced wear under extreme conditions. To examine whether increased contact pressures would adversely affect wear in thin liners, we tested thin and thick highly crosslinked liners (3.8 mm thickness/44-mm head and 7.9 mm thickness/36-mm head, respectively) to 5 million cycles on a hip simulator under near impingement conditions. Conventional polyethylene liners (7.9 mm thickness/36-mm head) served as controls. Large femoral heads with highly crosslinked polyethylene liners as thin as 3.8 mm in thickness do not wear at a higher rate than a thicker liner of the same material, even when subjected to large contact pressures such as occur under near-impingement conditions. Crosslinked polyethylene may allow for liners that are thinner than has been traditionally accepted. This conclusion, however, is based solely on wear test results with idealized cup position, no intentional edge loading, no head subluxation, and no artificial aging. Continued monitoring will be necessary to elucidate the clinical efficacy of these devices.

publication date

  • February 1, 2010

Research

keywords

  • Cross-Linking Reagents
  • Hip Prosthesis
  • Polyethylenes
  • Prosthesis Failure

Identity

PubMed Central ID

  • PMC2806988

Scopus Document Identifier

  • 76249110539

Digital Object Identifier (DOI)

  • 10.2106/JBJS.F.00758

PubMed ID

  • 19898911

Additional Document Info

volume

  • 468

issue

  • 2