title: Biotribology of a new bearing material combination in a rotating hinge knee articulation.
abstract: The objective of the present study was to evaluate the biotribological behaviour, in terms of wear and particle release, of bushings and flanges made of carbon fibre reinforced poly-ether-ether-ketone (CFR-PEEK) in articulation with a zirconium nitride (ZrN) multilayer surface coating in a rotating hinge knee system. For the bushings of the rotational and flexion axles and the medial and lateral flanges, a CFR-PEEK with 30% polyacrylonitrile fibre content was used in a new bearing combination with ZrN. In vitro wear simulation was performed for patients with metal ion hypersensitivity, using a new rotating hinge knee design with a ZrN surface articulation in comparison with the clinically established cobalt-chromium version. For the bushings and flanges made of CFR-PEEK subjected to wear simulation, the volumetric wear rates were 2.3±0.48mm(3)million(-1) cycles in articulation to cobalt-chromium as reference and 0.21±0.02mm(3)million(-1) cycles in the coupling with ZrN, a 10.9-fold decrease. The released CFR-PEEK particles were comparable in size and shape for the coupling to cobalt-chromium and ZrN with most of the particles in a size range between 0.1 and 2μm. The study reveals comparable low wear and no macroscopic surface fatigue in a new rotating hinge knee design with highly congruent flanges and axles bushings made of CFR-PEEK articulating to a ZrN multilayer surface coating. Favourable wear behaviour of the newly introduced CFR-PEEK/ZrN coupling in comparison with the clinically established CFR-PEEK/cobalt-chromium articulation was found.
authors.affiliation: Aesculap AG, Research & Development, Am Aesculap-Platz, D-78532 Tuttlingen, Germany. thomas.grupp@aesculap.de
authors.forename: T M
authors.initials: TM
authors.lastname: Grupp
authors.forename: A
authors.initials: A
authors.lastname: Giurea
authors.forename: R K
authors.initials: RK
authors.lastname: Miehlke
authors.forename: M
authors.initials: M
authors.lastname: Hintner
authors.forename: M
authors.initials: M
authors.lastname: Gaisser
authors.forename: C
authors.initials: C
authors.lastname: Schilling
authors.forename: J
authors.initials: J
authors.lastname: Schwiesau
authors.forename: C
authors.initials: C
authors.lastname: Kaddick
mesh_terms: D001577:Benzophenones; D001672:Biocompatible Materials / Q000737:chemistry*; D040761:Biomimetic Materials; D002244:Carbon / Q000737:chemistry*; D000077482:Carbon Fiber; D017276:Friction; D007659:Ketones / Q000737:chemistry*; D007719:Knee Joint / Q000502:physiology*; D054327:Lubricants / Q000737:chemistry*; D008153:Lubrication / Q000379:methods*; D008422:Materials Testing; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers; D016059:Range of Motion, Articular / Q000502:physiology*; D012399:Rotation
chemical_list: D001577:Benzophenones; D001672:Biocompatible Materials; D000077482:Carbon Fiber; D007659:Ketones; D054327:Lubricants; D011108:Polymers; C063834:polyetheretherketone; D011092:Polyethylene Glycols; D002244:Carbon