Shear wave elastography (SWE) for Achilles tendon evaluation faces challenges in standardization. This study examined the effects of ankle position, probe frequency, and physical effort on the shear modulus of the Achilles tendon, and assessed intra- and inter-observer reliability. In 37 healthy volunteers, the highest reliability was achieved using the L18-5 probe at 2 cm from the calcaneal insertion with the ankle in a neutral position. Significant variations in elasticity were found with different ankle positions and probes, but physical exercise had no significant impact. The study suggests that 10-20 degrees of plantar flexion is the optimal ankle position for SWE evaluation, highlighting the need for further research to standardize the technique.
