Ultrahigh molecular weight polyethylene (UHMWPE) bearings are used widely in orthopaedic joint replacement as a prominent material for improving the longevity, which is dramatically influenced by wear of polyethylene. Polyethylene tibial knee components from knee simulators under two different input conditions were analyzed using CMM and Micro-CT measurement techniques for volumetric loss with gravimetric measurement as reference. Based on the coordinates and image slices obtained, the surface curve fitting and image digitization methodology were used for the creation of nominal "original" surface in the case of no prewear data provided. The comparison results indicate that gravimetric remains the gold standard and the CMM measurement took less time and had better precision, accuracy, and repeatability compared to Micro-CT measurement technique.
Total knee replacement is a common surgical procedure in orthopaedics. Accurate volumetric wear assessment of the polyethylene knee inserts has been an essential subject for improving the longevity. A new CMM-based methodology was presented to determine volumetric material loss based on curve surface fitting without prewear data, CAD model, or original design of drawings. Both computational and experimental simulated volume removal tests were run to validate the methodology by comparing with the gravimetric measurements. The volume and linear wear of the tibial inserts were calculated using the presented method based on the coordinates acquired by the CMM. The results indicate that the methodology is adequate for clinically retrieved tibial inserts where no prewear data are provided. This technique can also be used for biotribological study of other polyethylene components, since wear and damage can be assessed visually and volumetrically.
Yang, W.;Marshall, A. M.;Wanatowski, D.;Stace, L. R.
Advances in Materials Science and Engineering,2017年2017 ISSN：1687-8434
[Yang, W.; Marshall, A. M.; Stace, L. R.] University of Nottingham, University Park, Nottingham;[Yang, W.; Marshall, A. M.; Stace, L. R.] NG72RD, United Kingdom;[Yang, W.] Key Laboratory of Transportation Tunnel Engineering, Ministry of Education, First North Section 111, Chengdu;[Yang, W.] 610031, China;[Wanatowski, D.] Southwest Jiaotong University, Leeds Joint School, Xipu Campus, Chengdu
[Yang, W] Univ Nottingham, Univ Pk, Nottingham NG7 2RD, England.;Minist Educ, Key Lab Transportat Tunnel Engn, First North Sect 111,Erhuan Rd, Chengdu 610031, Peoples R China.
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