title: Plasticity-induced damage layer is a precursor to wear in radiation-cross-linked UHMWPE acetabular components for total hip replacement. Ultra-high-molecular-weight polyethylene.
abstract: The mechanism for the improved wear resistance of cross-linked ultra-high-molecular-weight polyethylene (UHMWPE) remains unclear. This study investigated the effect of cross-linking achieved by gamma irradiation in nitrogen on the tribologic, mechanical, and morphologic properties of UHMWPE. The goal of this study was to relate UHMWPE properties to the wear mechanism in acetabular-bearing inserts. Wear simulation of acetabular liners was followed by detailed characterization of the mechanical behavior and crystalline morphology at the articulating surface. The wear rate was determined to be directly related to the ductility, toughness, and strain-hardening behavior of the UHMWPE. The concept of a plasticity-induced damage layer is introduced to explain the near-surface orientation of the crystalline lamellae observed in the wear-tested acetabular liners. Cross-linking reduces abrasive wear of acetabular components by substantially reducing--but not eliminating--the plasticity-induced damage layer that precedes abrasive wear.
authors.affiliation: Stryker Howmedica Osteonics, Allendale, New Jersey 07401, USA.
authors.forename: A A
authors.initials: AA
authors.lastname: Edidin
authors.forename: L
authors.initials: L
authors.lastname: Pruitt
authors.forename: C W
authors.initials: CW
authors.lastname: Jewett
authors.forename: D J
authors.initials: DJ
authors.lastname: Crane
authors.forename: D
authors.initials: D
authors.lastname: Roberts
authors.forename: S M
authors.initials: SM
authors.lastname: Kurtz
mesh_terms: D000077:Acetabulum; D019644:Arthroplasty, Replacement, Hip; D004548:Elasticity; D006801:Humans; D008422:Materials Testing; D011095:Polyethylenes; D011475:Prosthesis Failure; D013718:Tensile Strength
chemical_list: D011095:Polyethylenes; C111601:ultra-high molecular weight polyethylene