Semirhythmic, Semicircular Movements of Head, Neck, Left Shoulder, and Scapular Regions

Resolution with voluntary activation, stretching, tactile stimulation and decubitus position. Needle electromyography of the left upper trapezius showing semirhythmic, 1-Hz to 2-Hz, 0.2- to 0.3-second bursts of grouped, normal motor unit potentials recruited in a crescendo-decrescendo pattern while standing but not while lying down.