HEMIBALISMUS Hemiballismus, a rare but important neurological movement disorder. It is characterized by sudden, violent, involuntary flinging movements affecting one side of the body, usually involving the arm and leg. Definition Hemiballismus is a hyperkinetic movement disorder marked by: Unilateral (one-sided) Large-amplitude, proximal limb movements Irregular, forceful, flinging or throwing-type motions Clinical Features Patients typically present with: Sudden onset of violent, jerky, flingin