TREMORS Flashcards
________may be defined as involuntary rhythmic oscillatory movement produced by alternating or irregularly synchronous contractions of reciprocally innervated
muscles
Tremor
embedded i n the motor system.
It is present in all contracting muscle groups and persists throughout the waking state and even in certain phases of sleep
Physiologic Trem o r
Frequency of physiologic tremor
It ranges in frequency between 8 and
13 Hz, the dominant rate being 10 Hz in adulthood and
somewhat less in childhood and old age
Action tremors can be conveniently
divided into two categories: ________action
tremor of the ataxic type related to cerebellar disorders
and ________, which are
either the enhanced physiologic variety or essential
tremor
goal directed
postural tremors
the tremor is absent when the limbs are relaxed but becomes evident when the muscles are activated
postural tremors
Most cases of __________
are characterized by relatively rhythmic bursts of grouped motor neuron discharges that occur not quite synchronously in opposing muscle groups
action tremor
This, the commonest type o f tremor, i s o f lower frequency (4 to 8 Hz) than physiologic tremor and is unassociated with other neurologic changes;
ET
Like most tremors, essential tremor is worsened by ________________
emotion, exercise, and fatigue.
Inheritance of ET
autosomal dominant pattern with high penetrance.
Essential tremor most often makes its appearance
late in the_________ but it may begin in childhood and then persist.
second decade,
in ET..
The tremor practically always begins in the ______
and is usually almost_______ in approximately
________ of patients, however, it may appear first in
the dominant hand.
arms
symmetrical;
15 percent
Most patients with essential tremor will have
identified the amplifying effects of anxiety and the ameliorating
effects of _______ on their tremor.
alcohol
A curious fact about essential tremor o f the typical
(non-alternate-beat) type is that it can be suppressed
by a small amount of alcohol in more than ______percent
of patients
75
essential tremor is
inhibited by the beta-adrenergic antagonist __________ taken orally over a long
period of time.
propranolol
(between 80 and 200 mg per day in divided doses or as
a sustained-release preparation)
The barbiturate drug ________ has also been effective
in controlling essential tremor and may be tried
in patients who do not respond to or cannot tolerate
beta-blocking medications
primidone
Most patients with essential tremor will have
identified the amplifying effects of anxiety and the ameliorating
effects of _______ on their tremor.
alcohol
A curious fact about essential tremor o f the typical
(non-alternate-beat) type is that it can be suppressed
by a small amount of alcohol in more than ______percent
of patients
75
essential tremor is
inhibited by the beta-adrenergic antagonist __________ taken orally over a long
period of time.
propranolol
(between 80 and 200 mg per day in divided doses or as
a sustained-release preparation)
The barbiturate drug ________ has also been effective
in controlling essential tremor and may be tried
in patients who do not respond to or cannot tolerate
beta-blocking medications
The alternate-beat, slow, high-amplitude, kinetic-predominant type of essential tremor is more difficult to suppress but has reportedly responded to_______
primidone
clonazepam
Injections of _________into a portion of a limb
can reduce the severity of essential tremor locally; but the accompanying weakness of arm and hand muscles often proves unacceptable to the patient
botulinum toxin
In resistant cases of essential tremor of the fast or
slow variety, stimulation by electrodes implanted in the
_________ (of the same type used to treat
Parkinson disease) has produced a durable response
over many years; d
ventral medial nucleus thalamus or the internal segment
of the globus pallidus
A coarse action tremor, sometimes combined
with myoclonus, accompanies various types of
_________
meningoencephalitis
EMG of PD Tremor
bursts of activity that alternate between opposing muscle
groups
Parkinsonian tremor is_________ in the sense
that it takes the form of flexion-extension or abductionadduction
of the fingers or the hand; pronation-supination
of the hand and forearm is also a common presentation.
“alternating”
The cogwheel effect, a ratchet-like interruption perceived
by the examiner on passive movement of an
extrernitiy __________
It is said by many authors
to be no more than a palpable tremor superimposed
on rigidity and as such, is not specific for Parkinson
(the Negro sign) .
Cogwheeling can
be brought out by having the patient engage the opposite
limb, such as tracing circles in the air; what sign?
this Froment sign
The tremor of _________ (which is
now virtually extinct) often had greater amplitude and
involved proximal muscles
postencephalitic parkinsonism
Parkinsonian tremor is suppressed to some extent by
the anticholinergic drugs _________________
and other anticholinergic drugs such as ethopropazine,
a phenothizine derivative;
benztropine, trihexyphenidyl,
In PD
Stereotactic lesions or electrical
stimulation in the _______ diminishes or abolishes tremor contralaterally;
other stimulation sites such as the ___________ and the subthalamic nucleus
basal ventrolateral nucleus of the
thalamus
internal segment
of the globus pallidus
Its salient
feature is that it requires for its full expression the performance
of an exacting, precise, projected movement
Ataxic tremor
This is a strongly familial episodic tremor disorder of
the chin and lower lip that begins in childhood and
may worsen with age.
geniospasm
This is a rare but striking tremor isolated to the legs that
is remarkable by its occurrence only during quiet standing
and its cessation almost immediately on walking.
Pri m a ry Orthostatic Trem o r
Tx for primary orthostatic tremor
clonazepam, gabapentin, primidone, or sodium valproate
alone
______ is focal, superimposed, for example on
torticollis, or it may be evident in a hand
Dystonic tremor
usually restricted to a single limb, often in the dominant
hand; they are gross in nature, are less regular than
the common static or action tremors, and diminish in
amplitude or disappear if the patient is distracted as, for example, when asked to make a complex movement with
the opposite hand.
Psych ogenic Trem o r
If the examiner restrains the affected
hand and arm, the tremor may move to a more proximal part of the limb or to another part of the body________
(“chasing
the tremor”)
I n patients with tremor o f either the parkinsonian,
postural, or intention type, Narabayashi has recorded burst in _______
rhythmic burst discharges of unitary cellular activity in
the nucleus intermedius ventralis of the thalamus (as
well as in the medial pallidum and subthalamic nucleus)
in ET, Based on electrophysiologic
recordings in patients, two likely origins of
oscillatory activity are the ______ circuits and the
_____
olivocerebellar and thalamus.
PD lesion
ventromedial tegmentum of the midbrain,
brachium conjunctivum, or a tegmental-thalamic projection, or the
descending limb of the superior cerebellar peduncle
lesion of ataxic tremor
inactivating the
deep cerebellar nuclei or by sectioning the superior cerebellar
peduncle or the brachium conjunctivum below its
decussation.
This i s a rare disorder consisting o f rapid, rhythmic,
involuntary movements of the soft palate.
Pa lata l Trem o r ( “ Pa l ata l Myocl o n u s “ }
2 types of Palatal tremor
One is essential palatal tremor that reflects the rhythmic activation of the _________ it has no known pathologic basis.
second, more common form is a symptomatic palatal
tremor caused by a diverse group of brainstem lesions
that interrupt the ________(s); these columns
contain descending fibers ________________________ (a component of the GuillainMollaret
triangle
tensor veli palatini muscles;
central tegmental tract
from midbrain nuclei to the inferior olivary complex
Tx of palatal myoclonus
Clonazepam (0.25 to 0.5
mg/ d, increasing gradually to 3.0 to 6.0 mg/d), sodium
valproate (250 mg/ d, increasing to 1 ,000 mg/ d), and gabapentin
(up to 2,100 mg)
It consists of arrhythmic lapses of sustained
posture that allow gravity or the inherent elasticity of
muscles to produce a movement, which the patient then
corrects, sometimes with overshoot.
asterixis
EEG and EMG of Asterixis
that a sharp wave, probably generated
in the motor cortex, immediately precedes the period of
EMG silence
Asterixis may also be evoked by _______ and other
anticonvulsants, usually indicating that these drugs are
present in excessive concentrations
phenytoin