Changes in Achilles Tendon Compliance from 30 Days of Chronic Unloading and Subsequent 3 Weeks of Rehabilitation An MR Phase Contrast Study at 3T
Shin D, Ahn S, Sinha S, Lee H, Hodgson J, Edgerton R, Finni T
University of California
We used phase contrast cine magnetic resonance imaging to quantify tendon compliance. This study aims to (i) show the feasibility of using PC MRI technique for noninvasive measurement of the Achilles tendon compliance with significant precision and accuracy and (ii) quantify changes in the tendon compliance from 30 days of chronic unloading and consequent atrophy followed by 6 weeks of physical rehabilitation. The stiffness decreased as a result of muscle atrophy and gradually recovered to near normal level by the end of 3 weeks. These changes of compliance seem to indicate that muscle atrophy elicits changes not only in muscle activity but also in material properties of passive tissues.