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Updated: May 5, 2026
07:50
Measuring Local Tissue Strains in Tendons via Open-Source Digital Image Correlation
Published on: January 27, 2023
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Functionally distinct tendon fascicles exhibit different creep and stress relaxation behaviour
Jennifer H Shepherd1, Kirsten Legerlotz, Taylan Demirci
1Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary, University of London, London, UK.
Summary
Investigating tendon fatigue is crucial for understanding overuse injuries. Energy-storing tendons, like the human hamstring, show superior fatigue resistance compared to positional tendons, despite similar damage levels.
Area of Science:
- Biomechanics
- Tendon Physiology
- Musculoskeletal Research
Background:
- Overuse tendinopathies are linked to repetitive microstrain below failure threshold.
- Animal models are used for in vitro tendon fatigue studies, but species-specific differences exist.
- Current animal models may not accurately reflect human tendon responses to overuse injuries.
Purpose of the Study:
- To compare the fatigue response of different tendon types under controlled loading conditions.
- To investigate the fatigue resistance of positional versus energy-storing tendons.
- To evaluate the suitability of animal models for human tendon overuse research.
Main Methods:
- Bovine digital extensor, bovine deep digital flexor, and human semitendinosus tendon fascicles were used.
- Tendon fascicles underwent stress-controlled (cyclic creep) or strain-controlled (cyclic stress relaxation) fatigue loading.
- Mechanics were monitored, and cycles to failure were recorded.
Main Results:
- Bovine extensor fascicles exhibited the poorest fatigue response.
- Human semitendinosus (energy-storing) tendons were the most fatigue resistant.
- All tendon types showed similar levels of microscopic damage, suggesting energy-storing tendons tolerate damage better.
Conclusions:
- Energy-storing tendons possess superior fatigue resistance compared to positional tendons.
- Tendon mechanics can be maintained despite significant microscopic damage in energy-storing types.
- Findings highlight the importance of considering tendon function when selecting models for overuse injury research.
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