title: Cushion form bearings for total knee joint replacement. Part 1: Design,friction and lubrication.
abstract: Cushion knee prostheses have been designed and constructed that produce approximately equal initial contact areas and theoretical film thicknesses compared with a conventional UHMWPE (ultra-high molecular weight polyethylene) joint. These compliant bearings had a flat tibial component which imposed fewer biomechanical constraints and allowed a greater range of movement. Friction experiments have been carried out on a pendulum simulator apparatus. The results showed that the cushion knee joints operated just within the mixed lubrication regime, but that they benefited from a substantial measure of fluid film lubrication. Microelastohydrodynamic lubrication was effective in preserving low friction and thin but effective lubricating films.
mesh_terms: D001696:Biomechanical Phenomena; D002266:Carboxymethylcellulose Sodium / Q000737:chemistry; D003187:Compliance; D017276:Friction; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D007720:Knee Prosthesis; D008153:Lubrication; D008422:Materials Testing; D011474:Prosthesis Design; D016059:Range of Motion, Articular; D012996:Solutions / Q000737:chemistry; D014783:Viscosity
chemical_list: D012996:Solutions; D002266:Carboxymethylcellulose Sodium