Finite Element Modeling of Muscle Microstructure
Author:Jaden Lee ’22
Faculty Mentor(s):Benjamin Wheatley, Mechanical Engineering
Funding Source:John P and Mary Jane Swanson Professorship in Engineering & the Sciences
Clinical treatments for muscle conditions such as muscle atrophy and cerebral palsy require an understanding of the mechanical properties of the impaired tissue. The extracellular matrix (ECM) is a collagen-based, honeycomb-like structure present throughout muscle tissue that greatly influences muscle stiffness. Although many studies have investigated the mechanical properties of muscle tissue and the ECM, there is scarce literature on the effect of different loading conditions on the functionality of the ECM. The goal of this study is to develop a finite element model of a muscle fascicle unit in order to understand how muscle stiffness may be dictated by the ECM. We hypothesize that the geometric parameters and material properties of the ECM such as thickness, fiber alignment, and hyperelasticity impact the mechanical properties of muscle tissue subject to various mechanical loading conditions. A transversely uniform representative volume element of muscle tissue was developed in Solidworks using a Voronoi-based cross-section. The model was discretized into tetrahedral finite elements using an open-source meshing package. Using FEBio, we will simulate the effects of uniaxial and biaxial stretching on the element with variations in ECM geometric and material properties. This theoretical model will then be used to link tissue-level mechanical function (stiffness) to tissue microstructure, thus providing insight into how impaired muscle may differ mechanically and structurally from healthy muscle.