Supersonic shear wave elastography of human tendons is associated with in vivo tendon stiffness over small strains

TY - JOUR

T1 - Supersonic shear wave elastography of human tendons is associated with in vivo tendon stiffness over small strains

AU - Mifsud, Tiziana

AU - Chatzistergos, Panagiotis

AU - Maganaris, Constantinos

AU - Chockalingam, Nachiappan

AU - Padhiar, Nat

AU - Stafrace, Kirill Micallef

AU - Gatt, Alfred

N1 - Publisher Copyright: © 2023 The Author(s)

PY - 2023/5

Y1 - 2023/5

N2 - Supersonic shear wave (SW) elastography has emerged as a useful imaging modality offering researchers and clinicians a fast, non-invasive, quantitative assessment of tendon biomechanics. However, the exact relationship between SW speed and in vivo tendon stiffness is not intuitively obvious and needs to be verified. This study aimed to explore the validity of supersonic SW elastography against a gold standard method to measure the Achilles tendon's in vivo tensile stiffness by combining conventional ultrasound imaging with dynamometry. Twelve healthy participants performed maximal voluntary isometric plantarflexion contractions (MVC) on a dynamometer with simultaneous ultrasonographic recording of the medial gastrocnemius musculotendinous junction for dynamometry-based measurement of stiffness. The tendon's force–elongation relationship and stress–strain behaviour were assessed. Tendon stiffness at different levels of tension was calculated as the slope of the stress–strain graph. SW speed was measured at the midportion of the free tendon and tendon Young's modulus was estimated. A correlation analysis between the two techniques revealed a statistically significant correlation for small strains (r(10) = 0.604, p =.038). SW-based assessments of in vivo tendon stiffness were not correlated to the gold standard method for strains in the tendon>10 % of the maximum strain during MVC. The absolute values of SW-based Young's modulus estimations were approximately-three orders of magnitude lower than dynamometry-based measurements. Supersonic SW elastography should be only used to assess SW speed for the detection and study of differences between tissue regions, differences between people or groups of people or changes over time in tendon initial stiffness (i.e., stiffness for small strains).

AB - Supersonic shear wave (SW) elastography has emerged as a useful imaging modality offering researchers and clinicians a fast, non-invasive, quantitative assessment of tendon biomechanics. However, the exact relationship between SW speed and in vivo tendon stiffness is not intuitively obvious and needs to be verified. This study aimed to explore the validity of supersonic SW elastography against a gold standard method to measure the Achilles tendon's in vivo tensile stiffness by combining conventional ultrasound imaging with dynamometry. Twelve healthy participants performed maximal voluntary isometric plantarflexion contractions (MVC) on a dynamometer with simultaneous ultrasonographic recording of the medial gastrocnemius musculotendinous junction for dynamometry-based measurement of stiffness. The tendon's force–elongation relationship and stress–strain behaviour were assessed. Tendon stiffness at different levels of tension was calculated as the slope of the stress–strain graph. SW speed was measured at the midportion of the free tendon and tendon Young's modulus was estimated. A correlation analysis between the two techniques revealed a statistically significant correlation for small strains (r(10) = 0.604, p =.038). SW-based assessments of in vivo tendon stiffness were not correlated to the gold standard method for strains in the tendon>10 % of the maximum strain during MVC. The absolute values of SW-based Young's modulus estimations were approximately-three orders of magnitude lower than dynamometry-based measurements. Supersonic SW elastography should be only used to assess SW speed for the detection and study of differences between tissue regions, differences between people or groups of people or changes over time in tendon initial stiffness (i.e., stiffness for small strains).

KW - Achilles Tendon

KW - Elasticity Imaging Techniques

KW - Mechanical Stress

KW - Ultrasound Imaging

KW - Validity of results

UR - https://www.scopus.com/pages/publications/85151375502

U2 - 10.1016/j.jbiomech.2023.111558

DO - 10.1016/j.jbiomech.2023.111558

M3 - Article

C2 - 37004390

AN - SCOPUS:85151375502

SN - 0021-9290

VL - 152

JO - Journal of Biomechanics

JF - Journal of Biomechanics

M1 - 111558

ER -