Tremors of the Hand
Medically referred to as tremors (English: Tremor), hand tremors are generally not life-threatening; however, they can pose significant challenges in performing daily tasks. Furthermore, hand tremors may serve as an early caution sign for certain neurological and degenerative disorders. This condition is characterized by an inability to control the shaking of the hands, which can adversely affect the quality of life for the individual. Various medications can effectively manage this condition, though it’s worth noting that experiencing slight tremors after extending the arms forward for an extended time can be normal.
Causes of Hand Tremors
Hand tremors can arise from numerous factors, including but not limited to the following:
- Medication Side Effects: Certain medications, including those for asthma, amphetamines, caffeine, corticosteroids, some psychiatric and neurological conditions, antidepressants, lithium, and antihistamines, can trigger hand tremors.
- Lack of Sleep: Insufficient sleep may lead to neurological reactions that can result in hand tremors.
- Excessive Caffeine Intake: High caffeine consumption may provoke hand tremors.
- Neurological Disorders: Conditions that can cause hand tremors include:
- Multiple Sclerosis (MS): In individuals with MS, damage to areas within the central nervous system pathways that manage movement can lead to hand tremors.
- Stroke: A stroke occurs due to a blood clot forming and blocking an artery, preventing blood from reaching the brain.
- Traumatic Brain Injury: Injuries to the brain may damage the nerves involved in coordinating movement.
- Psychiatric Disorders: Conditions like depression and post-traumatic stress disorder (PTSD) may contribute to the occurrence of tremors.
- Inherited Degenerative Disorders: Examples include hereditary ataxia or fragile X syndrome.
- Other Causes: These may include mercury poisoning, hyperthyroidism, liver or kidney failure, anxiety, or panic.
Types of Hand Tremors
Based on Timing
Hand tremors can be categorized into two primary types based on when they occur:
- Resting Tremor: This type manifests when muscles are relaxed, such as when the hands are resting on the lap. Typically, only the hands or fingers tremble, and it is often associated with Parkinson’s disease.
- Action Tremor: Occurring during voluntary muscle movements, this type is further subdivided into various forms, including:
- Postural Tremor: This occurs when a person maintains their hands in a position against gravity, like extending the arms for an extended period.
- Kinetic Tremor: Linked to voluntary movement, such as moving the wrists or opening and closing the eyes.
- Intention Tremor: This type arises when an individual aims to perform a purposeful action, such as touching the nose with a finger. Typically, the tremor worsens as the individual approaches their target.
- Isometric Tremor: This occurs during voluntary muscle contraction without associated movement, such as when holding a heavy book without shifting.
Based on Cause and Nature
Hand tremors can also be classified based on their underlying cause and nature:
- Essential Tremor: Sometimes referred to as benign essential tremor, this is the most common form of abnormal tremors. It is a neurological disorder resulting in involuntary, rhythmic shaking and can impact any body part but primarily affects the hands during simple tasks like drinking from a cup or tying shoelaces. While not dangerous, this tremor often worsens over time, typically begins gradually, and may become more pronounced on one side of the body. It can also exacerbate with emotional stress, caffeine intake, or extreme temperatures.
- Parkinsonian Tremor: Parkinson’s disease is a neurodegenerative disorder affecting dopamine-producing neurons in a specific brain region. Symptoms generally develop slowly over the years and include resting tremor, bradykinesia, limb rigidity, and balance issues.
- Dystonic Tremor: This tremor manifests in individuals with dystonia, a movement disorder characterized by sustained muscle contractions leading to abnormal postures or painful positions, such as wry neck (torticollis) or writer’s cramp. Dystonic tremors may be irregular and often worsen with specific movements, though they can diminish with rest or by touching the affected area.
- Cerebellar Tremor: A slow tremor affecting limbs that appears at the end of purposeful movements, such as pressing a button or reaching out to touch the nose with a fingertip. This type may arise from cerebellar damage due to stroke, tumors, multiple sclerosis, or inherited degenerative diseases, and can sometimes relate to chronic alcohol dependence or excessive medication use.
- Psychogenic Tremor: Also known as functional tremor, this type often begins suddenly and may vanish unexpectedly, usually worsening with stress but disappearing when the individual is distracted.
- Orthostatic Tremor: Characterized by rhythmic muscle contractions occurring in the legs and torso immediately after standing.
- Physiological Tremor: This type can occur in anyone and is rarely noticeable to the naked eye, though symptoms can worsen due to intense emotions such as anxiety, fear, physical exhaustion, hypoglycemia, hyperthyroidism, heavy metal poisoning, stimulants, alcohol withdrawal, caffeine, or fever.