Achilles tendon plays a significant role in walking and sporting activities, particularly through ankle joint and lower limbs stability. Ultrasound imaging can be the first-line examination of choice for patients suspected of having Achilles tendon injury, which is more and more frequent. Nowadays, ultrasound elastography can be used to evaluate the viscoelasticity properties of Achilles tendon, however little is known about the reproducibility of the technique. This study aims to evaluate the reproducibility of supersonic shear imaging SWE™ Young's modulus measurements of shear wave velocity (m/s) in Achilles tendon and plantar fascia.

Inclusion Criteria:

• Volunteers with normal Achilles tendon:
• Normal adult aged over 18 years old;
• Without lower limb malformation;
• With no symptoms of Achilles tendon lesion and no negative results of routine ultrasound examination for a possible tendinopathy.

Exclusion Criteria:

• Subjects who failed to meet all inclusion criteria were will be automatically excluded;

• Subjects who did will not wish or could will not sign the informed consent in person.

• Volunteers with abnormal Achilles tendon for any of these reasons:

  • Lower limb malformation;
  • Achilles tendon pain, Achilles tendon disease, surgical history of Achilles tendon surgery, morphologic abnormalities of Achilles tendon ( gray-scale/color Doppler/MRI/plain film);
  • Suffer from systemic, metabolic and endocrine diseases, including but not limited to, diabetes, familial hyperlipidemia (FH), systemic lupus erythematosus (SLE), gout, ankylosing spondylitis, hyperthyroidism, chronic renal failure, etc.
  • Pregnant women;
  • Apply Ongoing hormone hormonal therapy;
  • Athletes

Healthy volunteers without any Achilles tendon disease