Tremors
Tremors are rhythmic, involuntary movements that can affect various parts of the body, including the hands, arms, legs, and head. They are generally characterized by their frequency, amplitude, and the specific body parts involved. Tremors can arise from a variety of causes, such as neurological damage, genetic conditions, or diseases like Parkinson's. Common triggers for exacerbation include stress, anxiety, fatigue, caffeine, and alcohol withdrawal. Tremors can be classified into two main types: rest tremors, which occur when the affected part is at rest, and action tremors, which happen during movement.
Symptoms of tremors may appear acutely or develop progressively over time and can vary significantly from person to person. Treatment options can include behavioral therapies, lifestyle adjustments, and medications like beta-blockers or anticonvulsants. In some cases, more invasive procedures such as deep-brain stimulation or stereotactic brain surgery may be considered. Understanding the specific type and cause of tremors is crucial for effective management and treatment.
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Subject Terms
Tremors
ALSO KNOWN AS: Trembling, shaking
ANATOMY OR SYSTEM AFFECTED: Arms, feet, hands, head, legs, muscles, nerves, nervous system, throat
DEFINITION: Rhythmic, oscillating, and involuntary movements that vary with respect to frequency, amplitude, pattern, and anatomical site
CAUSES: Repeated contraction and relaxation of muscles; may result from neurological damage, inherited condition, or Parkinson’s disease and be aggravated by fear and anxiety, cold, stress, fatigue, caffeine, alcohol withdrawal, toxin exposure
SYMPTOMS: Involuntary movement, either with rest or with activity
DURATION: Acute or chronic and progressive
TREATMENTS: Depends on type and cause; may include anxiety management with cognitive-behavioral therapy, treatment of alcoholism, reduction of caffeine intake, sleep improvement, medications (dopamine receptor agonists, beta-blockers, anticonvulsants, benzodiazepines), stereotactic brain surgery, deep-brain stimulation
Causes and Symptoms
A very fine tremor is present in the limbs of all people and may be noticeable when the hand is outstretched. This normal tremor is aggravated by fear and anxiety, cold, stress, fatigue, caffeine, withdrawal, exposure, and a variety of drugs. For example, enhanced physiological tremor is a of antipsychotic drugs that interfere with dopamine uptake in the brain.
The immediate cause of tremor is the repeated contraction and relaxation of muscles. This muscular pattern may be the consequence of neurological damage to the extrapyramidal structures of the brain, including the basal ganglia, or may be an inherited condition.
Two major types are rest and action tremor. The former occurs when a person is resting and typically disappears or is reduced by voluntary movement, whereas the latter occurs when the person is active.
A “pill-rolling” rest tremor in the hand is usually the first noticeable sign of Parkinson’s disease; later, the arms and then the legs may become tremulous. If the rest tremor becomes severe enough, then a postural tremor occurs when maintaining a position against gravity. Hence, rest and action tremors may be present at the same time.
Essential tremor is hereditary and is erroneously called senile tremor. It typically affects one hand and then the other, progressing to the arms, and may involve the head and voice. Essential tremor tends to worsen with age and is most visible during slow movements.
Cerebellar tremor is a slow tremor that is visible with targeted, voluntary movements. The probable cause is damage to a cerebellar pathway. This damage may be the result of disease, such as multiple sclerosis, stroke, or to the brain.
Psychogenic tremor is subconsciously controlled by the person. The symptoms and signs point to both rest and action tremors, complicating the diagnosis. The onset may be sudden. The tremor may diminish or disappear when the person is distracted, and there may be a history of somatization disorder. Metabolic disorders and liver or kidney failure resulting in damage can also manifest themselves as tremors, known as flapping tremors, which are characterized by oscillations of the hand between dropping and rising positions.
Treatment and Therapy
The treatment of tremor depends on the type. For example, nondrug interventions are sometimes appropriate for enhanced physiological tremor and may include managing with cognitive-behavioral therapy, treating alcoholism, reducing intake, improving sleep, and so on.
A variety of drugs can be used for the treatment of tremor, including dopamine agonists, beta-blockers, anticonvulsants, and benzodiazepines. For example, propanolol, a common beta-blocker, may reduce essential tremor as well as Parkinsonian tremors. Drug therapy is less effective for cerebellar tremor. Stereotactic brain surgery (involving spatial coordinates for precision) to destroy part of the thalamus and thus interrupt the circuitry generating tremors or deep-brain stimulation via an electric probe implanted in the thalamus may provide relief.
Bibliography
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