A drop attack is a sudden, unexpected fall to the ground that occurs without any warning, such as a trip or stumble. It is defined by its abrupt onset and the lack of an external cause to account for the collapse. A drop attack is a symptom of an underlying medical issue, not a diagnosis itself, and often causes great concern due to its unpredictable nature. The defining characteristic of a classic drop attack is that the person remains conscious throughout the entire event, which distinguishes it from fainting or syncope.
Defining the Phenomenon
A drop attack is characterized by an instantaneous loss of postural muscle tone, typically causing the legs to suddenly give way. The fall is abrupt and forceful, leading the individual to collapse directly to the floor. Crucially, the person remains fully aware of their surroundings during the short duration of the event, which usually lasts only a few seconds.
The sudden loss of strength means the individual cannot brace themselves, leading to a high risk of injury, particularly to the face or head. Recovery is typically rapid, and the individual can often stand up immediately and resume their activity without any lingering confusion or post-event symptoms. This quick return to normal function, combined with retained consciousness, makes the drop attack a distinct type of sudden fall.
Underlying Medical Conditions
The causes of drop attacks are diverse, stemming from issues in the inner ear, the circulatory system, or the central nervous system.
Inner Ear Causes
One specific cause related to the inner ear is Tumarkin’s otolithic crisis, which occurs in some patients with advanced Meniere’s disease. This is thought to result from a sudden, massive imbalance signal originating in the otolith organs, which are part of the vestibular system. Patients often describe the sensation as feeling suddenly pushed or thrown to the ground without experiencing the typical spinning vertigo associated with Meniere’s attacks.
Circulatory Causes
Circulatory issues can also be a factor, particularly those that temporarily reduce blood flow to the brainstem. This can manifest as a transient ischemic attack (TIA) affecting the vertebrobasilar circulation. Vertebrobasilar insufficiency involves a temporary reduction of blood supply through the arteries that feed the back of the brain, which controls balance and coordination. This lack of oxygen in the brainstem causes a sudden weakness in the legs, resulting in a fall without loss of consciousness.
Neurological Causes
From a neurological perspective, an atonic seizure, or epileptic drop attack, is another cause. Atonic means “without tone,” and these seizures involve a sudden, generalized loss of muscle strength. While the classic definition requires full consciousness, atonic seizures can sometimes involve a momentary loss of awareness, complicating the clinical distinction. Other neurological causes include tumors or conditions that affect the brain’s control centers for posture and movement.
Diagnostic Procedures
Diagnosing the cause of a drop attack requires a comprehensive evaluation to differentiate it from other types of falls, such as syncope or seizures. The initial step involves a detailed medical history, focusing on the exact circumstances of the fall and whether consciousness was maintained. Witness accounts are often invaluable for clarifying the features of the event.
Neurological and Circulatory Testing
To investigate potential neurological causes, a physician may order an electroencephalogram (EEG) to record the electrical activity of the brain. Imaging studies, such as MRI or CT scans, are used to identify structural issues like tumors or signs of vascular compromise. For suspected circulatory causes, a full cardiovascular assessment is necessary, which can include an electrocardiogram (ECG), Holter monitoring to track heart rhythm, and a tilt table test to evaluate blood pressure responses to changes in posture.
Vestibular Testing
If an inner ear cause is suspected, specialized testing is employed. These tests may include an electronystagmogram (ENG) or videonystagmography (VNG), which record eye movements to assess the function of the balance system. Electrocochleography (ECog) may also be used to measure electrical responses within the inner ear, which can help confirm a diagnosis like Meniere’s disease. The goal of this workup is to pinpoint the exact physiological mechanism responsible for the sudden loss of postural control.
Therapeutic Approaches and Prevention
Management of drop attacks depends entirely on identifying and treating the underlying cause. If the cause is an atonic seizure, anti-epileptic medications are the primary treatment strategy to reduce the frequency and severity of the episodes. For drop attacks related to Meniere’s disease, management may involve dietary changes, such as salt restriction, or medications to manage inner ear fluid.
When attacks are linked to vascular issues like vertebrobasilar insufficiency, treatment focuses on managing cardiovascular risk factors. This includes medications to control high blood pressure, cholesterol, and diabetes, and sometimes surgical intervention to improve blood flow. Beyond treating the cause, safety measures are implemented to prevent serious injury from future falls, such as wearing protective headgear and modifying the living environment by removing trip hazards.