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Reflex of the Gracilis in Brain Death
Han Uk Ryu1,2, Sang Yeon Kim1, Hyun Goo Kang1,2
1Department of Neurology, Jeonbuk National University Medical School and Hospital, Jeonju 54907, Korea.
Abstract:
In patients with brain death, reflex movements originating from spinal reflexes are observed intermittently. Generally, they can occur under hypoxic stimuli such as when the ventilator is removed, under physical stimuli such as bending the neck, or under hypotension. Finger- and toe-jerk responses are commonly observed reflex movements that can occur in patients with brain death. In addition, the Lazarus sign, known as the most dramatic reflex movement, appears mainly in the upper extremities (e.g., the hands and arms) and in the distal lower extremities (e.g., the soles and toes). This case showed a reflex movement that was triggered by the contraction of the gracilis, a proximal muscle in the lower extremities, with only a gentle stimulus on the sole.
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