Changes in subchondral bone structure and mechanical properties do not substantially affect cartilage mechanical responses - A finite element study.

Autor: Orava H; Department of Applied Physics, University of Eastern Finland, Kuopio, Finland; Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland. Electronic address: heta.orava@uef.fi., Huang L; Department of Applied Physics, University of Eastern Finland, Kuopio, Finland., Ojanen SP; Department of Applied Physics, University of Eastern Finland, Kuopio, Finland; Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland., Mäkelä JTA; Department of Applied Physics, University of Eastern Finland, Kuopio, Finland., Finnilä MAJ; Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland., Saarakkala S; Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland., Herzog W; Mechanical & Manufacturing Engineering, Schulich School of Engineering, University of Calgary, Calgary, Canada., Korhonen RK; Department of Applied Physics, University of Eastern Finland, Kuopio, Finland., Töyräs J; Department of Applied Physics, University of Eastern Finland, Kuopio, Finland; Science Service Center, Kuopio University Hospital, Kuopio, Finland; School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia., Tanska P; Department of Applied Physics, University of Eastern Finland, Kuopio, Finland. Electronic address: petri.tanska@uef.fi.
Jazyk: angličtina
Zdroj: Journal of the mechanical behavior of biomedical materials [J Mech Behav Biomed Mater] 2022 Apr; Vol. 128, pp. 105129. Date of Electronic Publication: 2022 Feb 13.
DOI: 10.1016/j.jmbbm.2022.105129
Abstrakt: Subchondral bone structure has been observed to change in osteoarthritis (OA). However, it remains unclear how the early-stage OA changes affect the mechanics (stresses and strains) of the osteochondral unit. In this study, we aim to characterize the effect of subchondral bone structure and mechanical properties on the osteochondral unit mechanics. A 3-D finite element model of the osteochondral unit was constructed based on a rabbit femoral condyle μCT data and subjected to creep loading in indentation. Trabecular bone volume fraction, subchondral bone plate thickness, and equilibrium modulus were varied (including experimentally observed changes in early OA) to characterize the effect of these parameters on the osteochondral unit mechanics. At the end of the creep phase, the maximum principal strain at the bone surface of the cartilage-bone interface was decreased by 50% when the trabecular bone volume fraction was reduced from 48% to 28%. The maximum principal stress at the same location was decreased by 36% when plate thickness was reduced by 100 μm (-31%). In cartilage, small changes in the mechanics were seen near the cartilage-bone interface with a considerably thinner (-31%) plate. The changes in trabecular bone volume fraction, subchondral bone thickness and plate equilibrium modulus did not substantially affect the cartilage mechanics. Our results suggest that experimentally observed changes that occur in the subchondral bone structure in early OA have a minimal effect on cartilage mechanics under creep indentation loading; clear changes in the cartilage mechanics were seen only with an unrealistically soft subchondral bone plate.
(Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)
Databáze: MEDLINE
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