Clinical
diagnostic criteria for definite essential tremor.
Consensus
statement of the Movement Disorder Society on tremor
Inclusion
criteria
Bilateral postural tremor with or without
kinetic tremor, involving hands and forearms, that is visible and persistent
Duration >5 years
Exclusion
criteria
Other
abnormal neurological signs (except Froment's sign)
Presence of
known causes of increased physiological tremor
Concurrent
or recent exposure to tremorogenic drugs or the presence of a drug withdrawal
state
Direct or
indirect trauma to the nervous system within 3 months before the onset of
tremor
Historical
or clinical evidence of psychogenic origins
Convincing
evidence of sudden onset or evidence of stepwise deterioration
Washington
Heights–Inwood Genetic Study of Essential Tremor criteria
On
examination, a +2 postural tremor in at least one arm (a head tremor might also
be present, but is not sufficient for the diagnosis)
On
examination, there must be a +2 kinetic tremor during at least four tasks, or a
+2 kinetic tremor on one task and a +3 kinetic tremor on a second task. Tasks
include pouring water, using a spoon to drink water, drinking water,
finger-to-nose maneuver, and drawing spirals
If on
examination the tremor is present in the dominant hand, then by report it must
interfere with at least one activity of daily living (eating, drinking, writing
or using the hands). If on examination the tremor is not present in the
dominant hand, then this criterion is irrelevant
Medications,
hyperthyroidism, ethanol, and dystonia are not potential etiological factors
Symptoms
are not psychogenic (e.g. bizarre features, features inconsistent in character,
the patient is distractable, or other psychiatric features on examination)
0 to +3
tremor ratings: 0, no visible tremor; +1, tremor is of low amplitude, barely
perceivable, or intermittent; +2, tremor is of moderate amplitude (1–2 cm) and
usually present, and is clearly oscillatory; +3, tremor is of large amplitude
(>2 cm), violent, and jerky, resulting in difficulty completing the task
because of spilling or inability to hold a pen to paper
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