Evaluation of normal and pathological Achilles tendon by real-time shear wave elastography.

Tendinopathy covers a range of several tendon conditions, mostly caused by overuse but at least in Achilles tendon pathology, favored by obesity, diabetes, inflammatory and autoimmune conditions. Subclinical tendon pathology is difficult to diagnose, as magnetic resonance imaging (MRI) examinations are sometimes inconclusive and not cost-effective. Elastography is an ultrasound examination method that uses mechanical impulses to produce shear waves in the tissue of interest, then measures the tissue displacement and calculates the shear wave speed or the elastic modulus of the examined tissue. We have used B-mode ultrasonography and shear wave elastography on 80 Achilles tendons from healthy volunteers with or without tendon pathology history, and correlated the data obtained with the clinical parameters of the volunteers, such as age, body mass index (BMI) and sports practice. We have shown that there is no significant correlation between the elastic modulus of the Achilles tendon and age, sports practice and body mass index with the exception of the correlation between the elastic modulus of the right Achilles tendon in men and age. Shear wave elastography has proved to be cost-effective for the evaluation of the Achilles tendon in healthy volunteers and was able to monitor the evolution of one patient with old tendon rupture treated by surgery. It can complete MRI investigation and it can replace B-mode ultrasonography particularly in monitoring the post-surgery evolution.