Wrist to forearm ratio as a median nerve shear wave elastography test in carpal tunnel syndrome diagnosis.

Shear wave elastography (SWE) is an operator independent, developing form of ultrasound examination. It measures tissue elasticity by tracking shear wave velocity. In tissues of greater stiffness, shear waves travel faster (1). The median nerve in carpal tunnel syndrome (CTS) is entrapped influencing its elasticity; therefore, SWE can become an accessible screening test in CTS diagnosis.