Open AccessRelationship between mechanical properties (shear modulus and viscosity), age, and sex in uninjured Achilles tendons
Author(s) -
Sprague Andrew L.,
Awokuse Daniel,
Pohlig Ryan T.,
Cortes Daniel H.,
Grävare Silbernagel Karin
Publication year - 2020
Publication title -
translational sports medicine
Language(s) - English
Resource type - Journals
ISSN - 2573-8488
DOI - 10.1002/tsm2.148
Subject(s) - shear modulus , medicine , population , tendon , shear viscosity , body mass index , materials science , composite material , viscosity , surgery , environmental health
Tendon mechanical properties have been proposed as a biomarker of tendon health to track response to injury and treatment. Prior to utilizing these properties in an injured population, it is critical to understand how these are influenced by age and sex in an uninjured population. A retrospective analysis was conducted of 118 uninjured Achilles tendons to evaluate the relationship between tendon mechanical properties, age, and sex. Mechanical properties (shear modulus and viscosity) were assessed using continuous shear wave elastography. A moderator regression analysis was completed to examine the relationship between tendon mechanical properties, age, and sex, after adjusting for body mass index and physical activity level. There was an interaction between age and sex for shear modulus ( P = .049, R 2 change = .034). Females had a negative relationship between age and shear modulus ( P = .030, β = −0.350), but no relationship was observed for males ( P = .78, β = 0.031). A positive relationship was found between age and viscosity ( P = .034, β = 0.214). Increased viscosity was related to increased age with no difference between sexes. The effect of aging on shear modulus differed between men and women and may help explain sex‐specific injury risks and their differing response to mechanical load.