Related Experiment Video
Updated: Mar 22, 2026
Ultrasound Tissue Characterization of Human Achilles Tendon by Stability Quantification of Echo Patterns
Published on: September 5, 2025
Real-time sonoelastography using an external reference material: test-retest reliability of healthy Achilles tendons
Alessandro Schneebeli1, Filippo Del Grande2, Gabriele Vincenzo2
1Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland. alessandro.schneebeli@supsi.ch.
Sonoelastography (SE) reliably assesses Achilles tendon elasticity in relaxed and contracted states. Using an external reference material provides quantitative elasticity measurements, proving SE a simple and dependable technique.
Area of Science:
- Musculoskeletal imaging
- Biomechanics
- Medical physics
Background:
- Achilles tendon injuries are common, necessitating reliable assessment methods.
- Sonoelastography (SE) offers a non-invasive approach to evaluate tissue elasticity.
- Standardizing SE measurements requires reliable reference systems.
Purpose of the Study:
- To determine the test-retest reliability of sonoelastography (SE) for healthy Achilles tendons.
- To evaluate SE reliability in both relaxed and contracted tendon states.
- To assess the utility of an external reference system for quantitative elasticity measurements.
Main Methods:
- Forty-eight Achilles tendons from 24 healthy volunteers were examined using ultrasound and real-time SE.
- Measurements were taken with an external reference material in relaxed and contracted states.
- Intraclass correlation coefficient (ICC2.k) and Bland-Altman analysis assessed reliability.
Main Results:
- High to very high test-retest reliability was observed for SE measurements of Achilles tendons (ICC2.k: 0.91 relaxed, 0.93 contracted).
- Strain ratio (tendon/reference) reliability was high (ICC2.k: 0.87 relaxed) to very high (ICC2.k: 0.94 contracted).
- The Kager fat pad also demonstrated high reliability in both states.
Conclusions:
- Sonoelastography with an external reference material is a reliable and simple method for assessing Achilles tendon elasticity.
- The use of strain ratios provides a quantitative measure of tendon elasticity.
- SE shows promise for objective evaluation of Achilles tendon mechanical properties.
