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Updated: May 22, 2026

Muscle Function Obtained with Motion Mode Ultrasound and Surface Electromyography during Core Endurance Exercise
Published on: August 25, 2022
Electrically silent muscle visible by ultrasound
Francis O Walker1, James A Macdonald
1Department of Neurology, Wake Forest University School of Medicine, Winston-Salem, NC, USA. fwalker@wfubmc.edu
Abstract:
A 65-year-old woman with multiple chronic cranial neuropathies had spinal accessory innervated muscles that were virtually invisible to electromyography. Ultrasound imaging revealed the extensive atrophy and increased echogenicity that corresponded to the thinness of the muscles and their loss of insertional activity. In patients with severe atrophy of trapezius or sternocleidomastoid muscles, ultrasound may help in identify chronically denervated muscle.
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