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A type of involuntary movement affecting the proximal limb musculature, manifested in jerking, flinging movements of the extremity; caused by a lesion of or near the contralateral subthalamic nucleus. Usually only one side of the body is involved, resulting in hemiballismus.
Synonym(s): ballism
[G. ballismos, a jumping about]


See ballismus.


An extreme form of CHOREA in which the limbs are flung about violently. It is a disorder of the EXTRAPYRAMIDAL SYSTEM of the brain. STEREOTACTIC SURGERY may be helpful.

ballismus, ballism

violent flinging movements of the limbs, sometimes affecting only one side of the body (hemiballismus).