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Contracting biceps brachii elastic properties can be reliably characterized using supersonic shear imaging
Thomas Lapole1, Jérémy Tindel, Robin Galy
1Université de Lyon, Laboratoire de Physiologie de l'Exercice, 42023, Saint-Étienne Cedex 2, France, thomas.lapole@univ-st-etienne.fr.
European Journal of Applied Physiology
|November 5, 2014
Summary
This study shows that elastography can reliably measure the elastic properties of the biceps brachii muscle during contraction. This technique offers a new way to understand localized muscle adaptations.
Area of Science:
- Biomechanics
- Musculoskeletal research
- Medical imaging
Background:
- Traditional methods assess global muscle properties.
- Localized muscle mechanics are not well understood.
- Elastography offers potential for localized assessment.
Purpose of the Study:
- Assess feasibility and reliability of elastography for localized biceps brachii elastic properties.
- Investigate localized contracting muscle mechanical behavior.
Main Methods:
- Twelve subjects performed a controlled contraction.
- Synchronous measurement of joint torque, electromyography (EMG), and shear elastic modulus.
- Calculation of stiffness and compliance indexes using regression analysis.
Main Results:
- High determination coefficients (0.87-0.94) for relationships.
- Superior reliability for compliance index using logarithmic EMG values (CV 5.3 ± 4.1%).
- Excellent intra-class correlation coefficient (0.98 ± 0.01) and low measurement error.
Conclusions:
- Elastography reliably measures biceps brachii elastic properties during contraction.
- Proposed fitting method enhances reliability.
- Potential for new insights into localized muscle adaptations.
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