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Ultrasound Tissue Characterization of Human Achilles Tendon by Stability Quantification of Echo Patterns
Published on: September 5, 2025
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Spatial variations in Achilles tendon shear wave speed
Ryan J DeWall1, Laura C Slane2, Kenneth S Lee3
1Department of Radiology, University of Wisconsin-Madison, Madison, WI, USA; Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, USA.
Journal of Biomechanics
|June 17, 2014
Summary
Supersonic shear imaging reveals Achilles tendon shear wave speed varies with ankle posture and location. Speed decreases with plantarflexion and from the free tendon towards the musculotendon junction.
Area of Science:
- Biomechanics
- Medical Imaging
- Musculoskeletal Ultrasound
Background:
- Supersonic shear imaging (SSI) measures tissue elasticity via shear wave speed.
- Achilles tendon shear wave speed increases with loading due to strain-stiffening.
- Spatial variations in Achilles tendon mechanics are not well understood.
Purpose of the Study:
- Investigate spatial variations in Achilles tendon shear wave speed.
- Examine effects of ankle posture (resting, plantarflexion, dorsiflexion) on speed.
- Assess speed along medial and lateral paths from calcaneus to musculotendon junction.
Main Methods:
- Utilized supersonic shear imaging (SSI) on ten healthy adults.
- Measured shear wave speed in the Achilles tendon across three ankle postures.
- Recorded speeds along medial and lateral tendon paths at different locations.
Main Results:
- Significant spatial and posture-dependent variations in Achilles tendon shear wave speed were observed.
- Shear wave speed decreased from 12 m/s (resting) to 7.2 m/s (plantarflexed).
- Distal tendon speeds reached system limits (16.3 m/s) in dorsiflexion; speeds decreased proximally.
Conclusions:
- Achilles tendon shear wave speed is significantly influenced by ankle posture and spatial location.
- Lower speeds proximally suggest greater aponeurosis compliance compared to the free tendon.
- Accurate SSI assessments require careful consideration of limb posture and transducer positioning.
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