Researchers from the University of Wisconsin School of Medicine and Public Health used the technology to evaluate age-related changes of the Achilles tendon and calf muscle strain in adults. The study consisted of 10 young and 10 middle-aged adults (average age, 27 and 49, respectively).
Lead researcher Dr. Kenneth Lee and colleagues collected shear-wave images from regions of the Achilles tendon, including the muscle-free tendon, the soleus aponeurosis, and the medial gastrocnemius aponeurosis, measuring the shear-wave speeds of each site at three angles: resting, dorsiflexed, and plantarflexed.
The performance of supersonic shear imaging varied depending on imaging location and the ankle position; the technology was most effective when imaging the muscle-free tendon and increasing ankle dorsiflexion, the group found.
The results suggest that the elasticity of the Achilles tendon decreases with age. However, with middle-aged adults, elastography showed greater flexibility near the muscle-tendon junction, which could increase the risk of injury such as commonly seen with "tennis leg," the researchers concluded.