Assessment of Stress Distributions in a Skeletal Muscle Affected by Post-Stroke Spastic Myopathy

Abstract

This study aims to evaluate stress distributions in the medial gastrocnemius muscle (GM) of patients with spastic myopathy after stroke. Shear wave elastography was employed to measure the shear modulus in three specific regions (upper, middle, and lower) of the muscle in six participants (three healthy and three post-stroke). Shear modulus measurements served as inputs for a finite element model to estimate stress distributions during uniform muscle stretching. The skeletal muscle was modeled as a hyperelastic, incompressible, and inhomogeneous material. The results showed that the stress distribution tends to increase in the post-stroke group, particularly in the middle (+60%) and lower regions (+13%). These results demonstrate the feasibility of estimating stress distributions using SWE data in post-stroke conditions, highlighting potential for further optimization of both experimental protocols and numerical models. These advancements could ultimately provide valuable insights into the clinical challenges associated with understanding spastic myopathy pathologies.