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Fascicle-scale loading and failure behavior of the Achilles tendon
Oluseeni A Komolafe1, Todd C Doehring
1School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, PA 19104, USA.
Journal of Biomechanical Engineering
|April 8, 2010
Summary
The study found that individual Achilles tendon fascicles possess significantly higher stiffness than previously thought, suggesting a few strong fascicles may dominate the tendon's overall mechanical response.
Area of Science:
- Biomechanics
- Materials Science
- Orthopedics
Background:
- Limited understanding of fascicle-level biomechanical properties in Achilles tendons.
- Need for detailed fascicle properties to improve computational models.
Purpose of the Study:
- To investigate the mechanical properties of individual human Achilles tendon fascicles.
- To quantify fascicle-to-fascicle interactions and their influence on overall tendon behavior.
Main Methods:
- Uniaxial tensile testing of human Achilles tendon fascicle samples.
- Sequential sectioning to isolate single fascicles.
- Polarized light imaging with digital image correlation (DIC) for precise deformation measurement.
Main Results:
- Single fascicle modulus (226 MPa) was significantly higher than intact fascicle groups (68 MPa).
- Single fascicle stiffness was 3-4 times greater than intact specimens.
- Fascicle-to-fascicle interactions contributed less than 10% to the overall load response.
Conclusions:
- A subset of "strongest" fascicles may dominate the Achilles tendon's mechanical response.
- Fascicle-scale properties are crucial for accurate computational modeling of tendon behavior.
- This research provides valuable insights into the material properties of Achilles tendons at the fascicle level.
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