Essential tremor
Essential tremor is the most common movement disorder, defined as an isolated bilateral action tremor of the upper extremities present for at least 3 years, often with a positive family history. First-line pharmacologic treatment is propranolol or primidone; refractory, disabling tremor is treated with deep-brain stimulation or focused ultrasound thalamotomy.
- Topic reviewThe full article, organized the way the exam asks it.
- ABIM-format MCQsVignettes with an explanation for every wrong answer.
- Key factsThe numbers and thresholds worth memorizing, up front.
- AI tutorMedBrain answers the question you're stuck on.
What this article covers
- Overview
Definition: essential tremor is an isolated tremor syndrome of at least 3 years' duration, characterized by bilateral action tremor of the upper extremities, with or without tremor of the head…
- Epidemiology
Overall prevalence: affects 1% to 2% of the population, with prevalence rising sharply with age; some series report prevalence over 20% in adults older than 90 years.
- Risk factors
Family history of tremor: the single strongest risk factor; a first-degree relative with tremor markedly increases lifetime risk.
- Pathophysiology
Cerebellar-thalamic circuit dysfunction implicated: dysfunction of cerebellar-thalamic connections, particularly involving the ventral intermediate nucleus of the thalamus, is thought to underlie the…
- Clinical features
Diagnostic criteria (clinical): an isolated action tremor syndrome of the upper extremities (bilateral, though may be asymmetric) present for at least 3 years, without other neurologic signs…
- Differential diagnosis
Parkinson disease: produces an asymmetric rest tremor accompanied by bradykinesia, rigidity, and a shuffling gait; the tremor classically diminishes with voluntary movement, the opposite pattern from essential tremor.
- Diagnosis
Essential tremor is a clinical diagnosis: established by the history and examination criteria above (isolated bilateral action tremor for at least 3 years without other neurologic signs); no…
- Management
First step, mild tremor without functional impairment: reassurance and observation; pharmacologic treatment is reserved for tremor causing occupational, social, or self-care disability, since…
- Complications
Functional disability: progressive amplitude increase can impair writing, eating, drinking, dressing, and fine motor tasks, with downstream effects on employment and independence.
- Prognosis
Slowly progressive but not life-shortening: essential tremor does not reduce life expectancy and does not cause structural brain damage.
- Prevention
No established primary prevention: because the cause is not fully understood and much of the risk is genetic, there is no proven strategy to prevent the onset of essential tremor.
Read the whole article
Subscribing to Internal Medicine opens every article, the full question bank and MedBrain, on the web, iPhone and Android.
Related articles
- Parkinson disease
Parkinson disease is a slowly progressive neurodegenerative disorder from loss of substantia nigra dopaminergic neurons with alpha-synuclein Lewy body pathology, presenting with asymmetric rest tremor, bradykinesia, rigidity, and gait impairment. Diagnosis is clinical; first-line treatment is levodopa-carbidopa or a dopamine agonist.
- Parkinsonism
Parkinsonism is the clinical syndrome of bradykinesia plus rest tremor, rigidity, or postural instability, produced by idiopathic Parkinson disease or by secondary/atypical causes (drug-induced, vascular, Parkinson-plus syndromes, normal pressure hydrocephalus). Management treats the identified cause: stop the offending drug, shunt confirmed normal pressure hydrocephalus, or start levodopa for idiopathic disease.
- Dystonia
Dystonia is a movement disorder of sustained or intermittent muscle contractions causing repetitive, directional twisting postures; adult-onset focal forms (cervical dystonia, blepharospasm) are treated with botulinum toxin injection, while young-onset or progressive cases warrant a levodopa trial and screening for Wilson disease.
- Cerebellar stroke
Cerebellar stroke, ischemic or hemorrhagic infarction of the cerebellum, presents with vertigo, truncal ataxia, dysarthria, and limb incoordination and is diagnosed with brain MRI when CT is falsely reassuring. Its defining danger is delayed swelling that compresses the brainstem and fourth ventricle, which is treated with emergent decompressive suboccipital craniectomy.
- Wilson disease
Wilson disease is an autosomal recessive disorder of the ATP7B copper-transporting ATPase causing toxic copper accumulation in the liver, brain, and cornea, presenting with hepatic and/or neuropsychiatric disease usually before age 40; diagnosis rests on ceruloplasmin, urinary copper, and Kayser-Fleischer rings, and lifelong treatment is chelation with penicillamine or trientine, or zinc, unless liver transplant is required.
- Restless leg syndrome
Restless leg syndrome is a common sensorimotor disorder marked by an urge to move the legs with an uncomfortable sensation, worse at rest and in the evening, and relieved by movement. Diagnosis is clinical; management starts with correcting iron deficiency, then a dopamine agonist or an alpha-2-delta calcium channel ligand.