Hemiballismus

What it means

Hemiballismus is a rare movement disorder that is caused primarily by damage to various areas in the basal ganglia. Hemiballismus is usually characterized by involuntary flinging motions of the extremities. The movements are often violent and have wide amplitudes of motion. They are continuous and random and can involve proximal and/or distal muscles on one side of the body, while some cases even include the facial muscles. The more a patient is active, the more the movements increase. With relaxation comes a decrease in movements.

Hemiballismus is a very rare movement disorder. It is five hundred times rarer than Parkinson disease. Its effects can sometimes be severe enough to prevent patients from being able to perform daily functions. It is usually associated with structural brain lesions but can occur with metabolic abnormalities. The symptoms can also decrease while the patient is asleep, unlike some movement disorders. Ballism refers to very large-amplitude choreic movements of the proximal parts of the limbs, causing flinging and flailing limb movements. Ballism is most frequently unilateral, in which case it is referred to as hemiballism

Rare diseases that can present with this4

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Ballismus