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An insight on multiscale tendon modeling in muscle-tendon integrated behavior
Franco Maceri1, Michele Marino, Giuseppe Vairo
1Department of Civil Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133, Rome, Italy.
Biomechanics and Modeling in Mechanobiology
|July 9, 2011
Summary
A new multiscale tendon model captures nano and microscale nonlinearities, improving muscle-tendon unit (MTU) simulations. This refined model accurately predicts muscle force, reflecting adaptations from physical activity.
Area of Science:
- Biomechanics
- Tissue Engineering
- Computational Biology
Background:
- The accurate modeling of the muscle-tendon unit (MTU) is crucial for understanding human movement.
- Existing models often simplify tendon mechanics, neglecting crucial nonlinearities and adaptations.
- Tendon's hierarchical collagen structure influences its mechanical behavior at multiple scales.
Purpose of the Study:
- To develop and validate a refined tendon model incorporating multiscale elastic nonlinearities.
- To investigate the impact of physical activity-induced adaptations on tendon stiffness and MTU function.
- To integrate this advanced tendon model into a viscoelastic Hill-type MTU model.
Main Methods:
- A multiscale approach was used to model tendon's hierarchical collagen structure, from molecular to fiber levels.
- Tendon's varying stiffness due to physical activity was incorporated into the model.
- The refined tendon model was integrated into a Hill-type MTU model for numerical simulations.
- A fixed-end contraction test was simulated, comparing linear and nonlinear tendon models.
Main Results:
- The nonlinear tendon model successfully reproduced key mechanical features of the MTU.
- Accurate time-histories of muscle contractile force and fiber length were obtained using the nonlinear model.
- The model quantitatively recovered experimental data, highlighting the importance of tendon nonlinearities.
- Numerical results provided insights into how physical activity-induced remodeling affects muscle force.
Conclusions:
- Elastic nonlinearities at the nano and microscale are essential for accurate MTU modeling.
- The proposed multiscale tendon model offers a more realistic representation of tissue behavior.
- This refined model aids in understanding the functional consequences of tendon adaptation to physical activity.
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