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1. sudden fall without precipitant or associated symptoms or signs, generally in old people with normal electroencephalograms; of unknown cause;
2. atonic seizure.
a form of transient ischemic attack in which a brief interruption of cerebral blood flow causes a person to fall to the floor without losing consciousness. The fall may be caused by a disrupted sense of balance or decreased leg muscle tone. Weakness of the leg muscles or a hip or knee joint dysfunction may be a contributing factor.
Aetiology Idiopathic—most common in older women and attributed to age-related defects in reflexes; drop attacks also occur in vertibrobasilar ischaemia, acute labyrinthine vertigo, cataplexy, and ‘plateau waves’, and may be associated with loss of consciousness in syncope and seizures
drop attackNeurology An episodic and precipitous loss of motor function, where the victim is either standing or walking, and abruptly plummets, fully conscious to the floor, as the legs give way; idiopathic DAs are most common in older ♀, and attributed to age-related defects in reflexes; DAs may also occur in vertibrobasilar ischemia, acute labyrinthine vertigo, cataplexy, 'plateau waves'; DAs with loss of consciousness occur in syncope and seizures
drop at·tack(drop ă-tak')
An episode of sudden falling that occurs during standing or walking, without warning and without loss of consciousness. The patients are usually elderly and have normal findings on electroencephalograms.