Logo image
Implications of Using Simplified Finite Element Meshes to Identify Material Parameters of Articular Cartilage
Journal article   Peer reviewed

Implications of Using Simplified Finite Element Meshes to Identify Material Parameters of Articular Cartilage

Nicole E. Szabo, Joshua E. Johnson, Marc J. Brouillette and Jessica E. Goetz
Medical engineering & physics, Vol.131(1), 104200
09/2024
DOI: 10.1016/j.medengphy.2024.104200
PMID: 39284645

View Online

Abstract

•Finite element (FE) modeling can assist in deriving cartilage material parameters•2D-axisymmetric and flat 3D models simplify complex cartilage geometry•Porous viscohyperelastic material parameters vary with mesh simplification•Changes in material parameters translate to changes in computed tissue mechanics The objective of this work was to determine the effects of using simplified finite element (FE) mesh geometry in the process of performing reverse iterative fitting to estimate cartilage material parameters from in situ indentation testing. Six bovine tibial osteochondral explants were indented with sequential 5% step-strains followed by a 600 second hold while relaxation force was measured. Three sets of porous viscohyperelastic material parameters were estimated for each specimen using reverse iterative fitting of the indentation test with 1) 2D axisymmetric, 2) 3D idealized, and 3) 3D specimen-specific FE meshes. Variable material parameters were identified using the three different meshes, and there were no systematic differences, correlation to basic geometric features, nor distinct patterns of variation based on the type of mesh used. Implementing the three material parameter sets in a separate 3D FE model of 40% compressive strain produced differences in von Mises stresses and pore pressures up to 25% and 50%, respectively. Accurate material parameters are crucial in any FE model, and parameter differences influenced by idealized assumptions in initial material property determination have the potential to alter subsequent FE models in unpredictable ways and hinder the interpretation of their results.
Finite Element Analysis Mechanics Articular Cartilage in situ indentation Material Properties

Details

Metrics

9 Record Views
Logo image