Related Experiment Video
Updated: Jan 14, 2026
11:28
A Coupled Experiment-finite Element Modeling Methodology for Assessing High Strain Rate Mechanical Response of Soft Biomaterials
Published on: May 18, 2015
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Modeling Fatigue and Damage Development in the Annulus Fibrosus Using a Reactive Viscoelastic Framework
Lance L Frazer1, Sarah K Shaffer2, Jack Seifert3
1Department of Materials Engineering, Southwest Research Institute, San Antonio, Texas, USA. lance.frazer@swri.org.
Annals of Biomedical Engineering
|January 12, 2026
Summary
A new computational model accurately predicts annulus fibrosus damage from repetitive loading, aiding spine health management and recovery standards.
Area of Science:
- Biomechanics
- Computational modeling
- Soft tissue engineering
Background:
- The annulus fibrosus (AF) is crucial for spinal stability.
- Understanding AF damage under cyclic loading is vital for treating back pain.
- Existing models lack comprehensive prediction of both acute and chronic AF damage.
Purpose of the Study:
- To develop a predictive constitutive model for annulus fibrosus (AF) damage.
- To simulate acute and chronic damage development during repetitive loading.
- To enhance understanding of spinal soft tissue mechanics.
Main Methods:
- Implemented a reactive viscoelasticity and fatigue constitutive model for the AF.
- Modeled the AF as a three-component mixture (ground matrix, collagen, elastin).
- Calibrated and probabilistically validated the model using porcine AF experimental data.
Main Results:
- The model accurately replicated experimental data, including force variation and relaxation ratios.
- Observed correlations between collagen and elastin fiber parameters.
- Demonstrated low mean absolute error and captured elastin damage under cyclic loading.
Conclusions:
- The developed model provides a robust framework for understanding soft tissue damage.
- Highlights the need for further research into AF healing mechanisms.
- Potential applications in spine health management and activity-based recovery.
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