Hemiballismus

Rare, extreme form of the movement disorder chorea

Hemiballismus or hemiballism is a basal ganglia syndrome resulting from damage to the subthalamic nucleus in the basal ganglia. Hemiballismus is a rare hyperkinetic movement disorder, that is characterized by violent involuntary limb movements, on one side of the body, and can cause significant disability. Ballismus affects both sides of the body and is much rarer. Symptoms can decrease during sleep.

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