Session: MSNDC-06-02: Nonlinear and Computational Dynamics Aspects in Biomechanics

Paper Number: 90693

90693 - Multi-Layered Finite Element Model Provides Insights Into the Influence of Adjacent Tissues on Shear Wave Propagation in the Achilles Tendon 

Shear wave tensiometry is an emerging measurement techniqe used to gauge tendon loading in vivo based on shear wave propagation in the tissue. Prior human studies have observed that tendon shear wave speeds are lower than that predicted by a tensioned beam model of an isolated tendon. This may be a result of the added mass and inertial effects of adjacent, subcutaneous tissues. The objective of this study was to investigate the effect of subcutaneous tissue (i.e., subcutaneous fat) on shear wave propagation. We created a layered, dynamic finite element model of the Achilles tendon surrounded by subcutaneous fat. We performed three sets of 1000 simulations on a high throughput computing grid, varying applied tendon strain, fat density, and fat elastic modulus. The layered model predicted tendon shear wave speeds that are in the range of those observed in vivo. Tendon shear wave speeds also decreased with both increasing subcutaneous fat density and fat elastic modulus. This study suggests potential causal mechanisms for reductions in shear wave speed observed in vivo, and thus provides an improved basis for assessing tendon load via shear wave propagation metrics.

Keywords: Achilles tendon, subcutaneous fat, shear wave propagation, finite element model, multi-layered model.

Presenting Author: Jonathon Blank University of Wisconsin-Madison

Presenting Author Biography: Jonathon Blank is a 4th year PhD student in the UW Neuromuscular Biomechanics Lab and Biomechanical Advances in Medicine Lab at the University of Wisconsin-Madison. He is a recipient of the National Science Foundation Graduate Research Fellowship. Jon’s research interests include experimental and computational characterization of tendon and ligament mechanics and structure-function relationships, with targeted applications in orthopedic surgery and wearable kinetics.

Authors:

Jonathon Blank University of Wisconsin-Madison
Lauren Welte University of Wisconsin-Madison
Stephanie Cone University of Wisconsin-Madison
Darryl Thelen University of Wisconsin-Madison