Ballismus
Pronunciation: bal-LIZ-mus
Violent, involuntary, flinging movements of the limbs caused by subthalamic nucleus lesions.
Full Definition
Ballismus is a hyperkinetic movement disorder characterized by sudden, violent, involuntary flinging or throwing movements of the extremities. The condition most commonly affects one side of the body (hemiballismus) and is typically caused by lesions in the subthalamic nucleus or its connections. The movements are large-amplitude, proximal, and can be so severe that they interfere with daily activities and may cause injury. In neuro-rehabilitation settings, ballismus requires careful management including pharmacological intervention and protective measures, as the involuntary movements can impede therapeutic progress and functional recovery.
Usage
Usage note: When unilateral, specify as hemiballismus; distinguish from chorea by the violent, flinging quality.
In Context
- "The patient developed severe ballismus following a subthalamic stroke, requiring protective padding during therapy." — Clinical observation
- "Hemiballismus on the right side made functional training extremely challenging." — Occupational therapy note