2. Introduction
Tremor is an involuntary, rhythmic,
oscillatory movement of a body part.
It is the most common movement
disorder encountered in clinical
practice.
History and physical examination can
provide a great deal of certainty in
diagnosis
3. The most common tremor seen is
enhanced physiologic tremor,
followed by essential tremor and
parkinsonian tremor.
All tremors are more common in older
age
4.
5. ESSENTIAL TREMOR
The most common pathologic tremor.
In 50% of cases, transmitted as an autosomal
dominant .
affects 0.4 to 6 percent of the population.
Careful history reveals that patients with
essential tremor have it in early adulthood (or
sooner).
6. up to 25 % of those afflicted retire early
or modify their career path.
Essential tremor is an action tremor,
usually postural (but also kinetic and
rest tremors have also been described).
most obvious in the wrists and hands .
7. It is generally bilateral
No diagnostic criteria.
considered a diagnosis of exclusion.
It is responds to alcohol.
8. PARKINSONISM
clinical syndrome characterized by tremor,
bradykinesia, rigidity, and postural instability .
Causes of parkinsonism include:
Parkinson disease .
brainstem infarction.
multiple system atrophy.
medications that block or deplete dopamine, such
as methyldopa, metoclopramide ,haloperidol, and
risperidone
9. >70 % of patients have tremor as the
presenting feature.
The classic parkinsonian tremor begins
as a low-frequency, pill-rolling motion of
the fingers, progressing to forearm
pronation/supination and elbow
flexion/extension.
10. asymmetric, occurs at rest, and
becomes less prominent with voluntary
movement .
Although rest tremor is one of the
diagnostic criteria for Parkinson disease,
most patients exhibit a combination of
action and rest tremors.
11. ENHANCED PHYSIOLOGIC
TREMOR
present in all persons .
low-amplitude, high-frequency tremor at rest and
during action.
enhanced by anxiety, stress, and certain
medications and metabolic conditions.
do not need further testing
15. DYSTONIC TREMOR
rare tremor found in 0.03 % of the
population.
typically occurs in patients younger than
50 years.
usually irregular and jerky, and certain
hand or arm positions will extinguish the
tremor.
16. WILSON DISEASE
rare, autosomal recessive disorder.
manifests in persons five to 40 years of age .
sometimes with a “wing-beating” tremor
Serum ceruloplasmin level and 24-hour
urinary copper excretion
17. Diagnostic Approach
thorough history and physical
examination.
have the patients sit with their
hands in their laps, then stretch
arm and examine for cerebellar
signs
18. categorize the tremor based on its
activation condition, topographic
distribution, and frequency .
Frequency is generally classified as low
(less than 4 Hz), medium (4 to 7 Hz), or
high (more than 7 Hz)
Editor's Notes
Seen at primary health care
Tremors are classified as either resting or action (Table 1).8 A rest tremor occurs in a body part that is relaxed and completely supported against gravity (e.g., when resting an arm on a chair). It is typically enhanced by mental stress (e.g., counting backward) or movement of another body part (e.g., walking), and diminished by voluntary movement of the affected body part.3,9,10 Most tremors are action tremors, which occur with voluntary contraction of a muscle. Action tremors can be further subdivided into postural, isometric, and kinetic tremors.8,9 A postural tremor is present while maintaining a position against gravity. An isometric tremor occurs with muscle contraction against a rigid stationary object (e.g., when making a fist). A kinetic tremor is associated with any voluntary movement and includes intention tremor, which is produced with target-directed movement.
Careful history reveals that patients with essential tremor have it in early adulthood (or sooner), but most patients do not seek help for it until 70 years of age because of its progressive nature.
most obvious in the wrists and hands when patients hold their arms in front of themselves (resisting gravity); however, essential tremor can also affect the head, lower extremities, and voice
Persons with essential tremor typically have no other neurologic findings; therefore, it is often considered a diagnosis of exclusion
Parkinsonism is a clinical syndrome characterized by tremor, bradykinesia, rigidity, and postural instability. Many patients will also have micrographia, shuffling gait, masked facies, and an abnormal heel-to-toe test.
Parkinson disease is a chronic neurodegenerative disorder
those that stimulate the sympathetic nervous system (e.g., amphetamines, terbutaline, pseudoephedrine) and psychoactive medications (e.g., tricyclic antidepressants, haloperidol, fluoxetine [Prozac]).1,8,12 When medication review reveals a likely culprit, a trial off of this medication should be attempted.
Metabolic causes of tremor are varied.8 Initial workup of tremor may include blood testing for hepatic encephalopathy, hypocalcemia, hypoglycemia, hyponatremia, hypomagnesemia, hyperthyroidism, hyperparathyroidism, and vitamin B12 deficiency.8
For example, a high-frequency tremor that involves the head is much more likely to be essential tremor than parkinsonian tremor
A search must be made for associated diseases (e.g., sleep disorders because fatigued muscles may amplify physiologic tremor; polyneuropathy because lack of innervations may cause small involuntary movements that are interpreted as tremor). A family history of neurologic disease or tremor suggests a genetic component, as is often seen in essential tremor. A thorough medication history should be obtained to rule out drug-induced tremor. The patient should also be screened for drugs of abuse and alcohol consumption because alcohol overuse and withdrawal can cause tremor
