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Updated: Sep 10, 2025
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Biomechanical Characterization of Human Soft Tissues Using Indentation and Tensile Testing
Published on: December 13, 2016
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A closed-form expression for the relationship between shear modulus from shear wave elastography and tangent modulus
Luiz Carlos da Silva Nunes1, Liliam Fernandes de Oliveira2, Maria Clara Albuquerque Brandão2
1Mechanical Engineering Department, Fluminense Federal University (UFF), Niteroi-RJ, Brazil.
Medical Engineering & Physics
|August 20, 2025
Summary
This study introduces a new formula to estimate tendon stiffness using shear wave elastography. This method improves accuracy by linking acoustic and mechanical measurements for better material property analysis.
Area of Science:
- Biomechanics
- Biomaterials Science
- Medical Imaging
Background:
- Shear wave elastography (SWE) is used for in-vivo tendon mechanical property assessment.
- Correlation between acoustic measurements and shear modulus from mechanical testing requires clarification.
Purpose of the Study:
- Propose a closed-form expression to estimate the tangent modulus of tendons under tension.
- Combine tensile testing and elastography data for improved material property estimation.
Main Methods:
- Developed a 1D nonlinear model for tensile test data, covering the entire physiological range.
- Created a new empirical model for shear modulus response from elastography based on tensile stress.
- Derived a closed-form expression by integrating both models.
Main Results:
- Reanalyzed in vitro stress-strain and shear modulus data from human Achilles tendons.
- The proposed methodology reduces noise in stress-strain data, enhancing tangent modulus estimation.
- Tangent modulus estimates are less sensitive to numerical differentiation.
Conclusions:
- The derived expression provides a practical method for estimating tendon tangent modulus.
- This approach is applicable to tendons in various states (crimped or extended).
- Enables integration of in-vivo elastography with tendon constitutive models for material property analysis.
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