title: Wear characteristics of an unconstrained lumbar total disc replacement under a range of in vitro test conditions.
abstract: The effect of kinematics, loading and centre of rotation on the wear of an unconstrained total disc replacement have been investigated using the ISO 18192-1 standard test as a baseline. Mean volumetric wear rate and surface morphological effects were reported. Changing the phasing of the flexions to create a low (but finite) amount of crossing path motion at the bearing surfaces resulted in a significant fall in wear volume. However, the rate of wear was still much larger than previously reported values under zero cross shear conditions. Reducing the load did not result in a significant change in wear rate. Moving the centre of rotation of the disc inferiorly did significantly increase wear rate. A phenomenon of debris re-attachment on the UHMWPE surface was observed and hypothesised to be due to a relatively harsh tribological operating regime in which lubricant replenishment and particle migration out of the bearing contact zone were limited. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 46-52, 2017.
authors.affiliation: Institute of Medical and Biological Engineering, University of Leeds, Leeds, UK.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Hyde
authors.affiliation: Institute of Medical and Biological Engineering, University of Leeds, Leeds, UK.
authors.forename: John
authors.initials: J
authors.lastname: Fisher
authors.affiliation: Institute of Medical and Biological Engineering, University of Leeds, Leeds, UK.
authors.forename: Richard M
authors.initials: RM
authors.lastname: Hall
mesh_terms: D000818:Animals; D006801:Humans; D007403:Intervertebral Disc; D008159:Lumbar Vertebrae; D011095:Polyethylenes / Q000737:chemistry*; D033081:Shear Strength; D059145:Total Disc Replacement
chemical_list: D011095:Polyethylenes; C111601:ultra-high molecular weight polyethylene
keywords: Charité; Prodisc; TDR; biotribology; in motion artificial disc; total disc replacement; tribology; wear