title: Elasto-plastic contact analysis of an ultra-high molecular weight polyethylene tibial component based on geometrical measurement from a retrieved knee prosthesis.
abstract: The wear phenomenon of ultra-high molecular weight polyethylene (UHMWPE) in knee and hip prostheses is one of the major restriction factors on the longevity of these implants. Especially in retrieved knee prostheses with anatomical design, the predominant types of wear on UHMWPE tibial components are delamination and pitting. These fatigue wear patterns of UHMWPE are believed to result from repeated plastic deformation owing to high contact stresses. In this study, the elasto-plastic contact analysis of the UHWMPE tibial insert, based on geometrical measurement for retrieved knee prosthesis, was performed using the finite element method (FEM) to investigate the plastic deformation behaviour in the UHMWPE tibial component. The results suggest that the maximum plastic strain below the surface is closely related to subsurface crack initiation and delamination of the retrieved UHMWPE tibial component. The worn surface whose macroscopic geometrical congruity had been improved due to wear after joint replacement showed lower contact stress at macroscopic level.
authors.affiliation: Department of Mechanical Systems and Environmental Engineering, Faculty of Environmental Engineering, The University of Kitakyushu, 1-1, Hibikino, Wakamatsu-ku, Kitakyushu, Fukuoka, 808-0135, Japan.
authors.forename: C H
authors.initials: CH
authors.lastname: Cho
authors.forename: T
authors.initials: T
authors.lastname: Murakami
authors.forename: Y
authors.initials: Y
authors.lastname: Sawae
authors.forename: N
authors.initials: N
authors.lastname: Sakai
authors.forename: H
authors.initials: H
authors.lastname: Miura
authors.forename: T
authors.initials: T
authors.lastname: Kawano
authors.forename: Y
authors.initials: Y
authors.lastname: Iwamoto
mesh_terms: D000368:Aged; D001672:Biocompatible Materials; D003198:Computer Simulation; D019544:Equipment Failure Analysis / Q000379:methods*; D020342:Finite Element Analysis; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology* / Q000601:surgery*; D007720:Knee Prosthesis; D008422:Materials Testing / Q000379:methods*; D008954:Models, Biological; D011095:Polyethylenes / Q000737:chemistry*; D011475:Prosthesis Failure; D013499:Surface Properties; D013718:Tensile Strength
chemical_list: D001672:Biocompatible Materials; D011095:Polyethylenes; C111601:ultra-high molecular weight polyethylene