title: Friction of total hip replacements with different bearings and loading conditions.
abstract: Metal-on-ultra-high molecular weight polyethylene (UHMWPE) total hip replacements have been the most popular and clinically successful implants to date. However, it is well documented that the wear debris from these prostheses contributes to osteolysis and ultimate failure of the prosthesis, hence alternative materials have been sought. A range of 28 mm diameter bearings were investigated using a hip friction simulator, including conventional material combinations such as metal-on-UHWMPE, ceramic-on-ceramic (CoC), and metal-on-metal (MoM), as well as novel ceramic-on-metal (CoM) pairings. Studies were performed under different swing-phase load and lubricant conditions. The friction factors were lowest in the ceramic bearings, with the CoC bearing having the lowest friction factor in all conditions. CoM bearings also had low friction factors compared with MoM, and the trends were similar to CoC bearings for all test conditions. Increasing swing phase load was shown to cause an increase in friction factor in all tests. Increased serum concentration resulted in increased friction factor in all material combinations, except MoM, where increased serum concentration produced a significant reduction in friction factor.
authors.affiliation: Institute of Medical and Biological Engineering, School of Mechanical Engineering, University of Leeds, Leeds LS2 9JT, United Kingdom. menclb@leeds.ac.uk
authors.forename: Claire
authors.initials: C
authors.lastname: Brockett
authors.forename: Sophie
authors.initials: S
authors.lastname: Williams
authors.forename: Zhongmin
authors.initials: Z
authors.lastname: Jin
authors.forename: Graham
authors.initials: G
authors.lastname: Isaac
authors.forename: John
authors.initials: J
authors.lastname: Fisher
mesh_terms: D001672:Biocompatible Materials; D001696:Biomechanical Phenomena; D002516:Ceramics; D017276:Friction; D006622:Hip Prosthesis; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing / Q000295:instrumentation / Q000379:methods; D008670:Metals; D011095:Polyethylenes; D013314:Stress, Mechanical
chemical_list: D001672:Biocompatible Materials; D008670:Metals; D011095:Polyethylenes; C111601:ultra-high molecular weight polyethylene