2. Tremor
• Definition: rhythmic and oscillatory movement of a
body part with a relatively constant frequency and
variable amplitude
• Due to alternating contractions of agonist and antagonist
muscles in an oscillating, rhythmic manner.
• The most common movement disorder
3. Tremor
• Rest Tremor: tremor prominent at rest
• Although when a patient totally relaxes or sleeps, this tremor
usually disappears
• Postural Tremor: tremor revealed by maintenance of a
posture, such as extending the arms parallel to the
floor
• Kinetic (Intention) Tremor: tremor revealed while
moving the body part to and from a target
4. Tremor
• Action tremor has been used for both postural and
kinetic
• Terminal tremor: applies to the component of kinetic
tremor that exaggerates when approaching the target.
• Kinetic tremor is present throughout goal-directed movement
5. Tremor
• Physiologic tremor: tremor seen in normal individuals
that typically manifests as a mild, high-frequency,
postural or action tremor that is usually of no clinical
consequence and often is only appreciated with an
accelerometer.
• An enhanced physiologic tremor (EPT) can be seen in
up to 10% of the population, often in association with
anxiety, fatigue, underlying metabolic disturbance,
drugs, or toxins
7. Essential Tremor
• ET is the commonest movement disorder
• Affects ~5–10 million persons in the United States.
• It can present in childhood, but dramatically increases
in prevalence over the age of 70 years.
• High frequency tremor
• Most often manifest as a postural or kinetic tremor.
• Typically bilateral and symmetric, but may begin on one
side and remain asymmetric.
• Patients with severe ET can have an intention tremor
with overshoot and slowness of movement.
8. Essential Tremor
• Tremor involves the head in ~30% of cases, voice in
~20%, tongue in ~20%, face/jaw in ~10%, and lower
limbs in ~10%.
• Improved by alcohol and worsened by stress.
10. Essential Tremor
• The etiology and pathophysiology of ET are not known.
• ~50% of cases have a positive family history with an
autosomal dominant pattern of inheritance
11. Essential Tremor- Rx
• Many cases are mild - require no treatment
• Reassurance.
• Occasionally, tremor can be severe and interfere with
eating, writing, and activities of daily living.
• This is more likely to occur as the patient ages and is
often associated with a reduction in tremor frequency.
15. Dystonia
• Can range from minor contractions in an individual
muscle group to severe and disabling involvement of
multiple muscle groups.
• Dystonia is often brought out by voluntary
movements (action dystonia) and can become
sustained and extend to involve other body regions.
16. Dystonia
• It can be aggravated by stress and fatigue, and
attenuated by relaxation and sensory tricks such as
touching the affected body part
• Classification
• Based on age: Childhood vs adult
• Based on distribution: Focal, multifocal, segmental or
generalized
• Based on etiology: Primary vs. Secondary
17. Dystonia- Medical Rx
• Botulinum toxin treatment continues to be the first
choice treatment for most types of focal dystonia.
• Pharmacological and neurosurgical treatments have
also a role in the treatment algorithm
19. Chorea
• Rapid, semi purposeful, graceful, dance like, non
patterned involuntary movements involving distal or
proximal muscle groups
20. Huntington’s Diseases
• George Huntington in 1872
• HD is a fatal, highly penetrant autosomal dominant
disease characterized by a progressive motor,
behavioral and cognitive dysfunction
• Onset 25-45 yrs
21. HD- Etiology
• Caused by an increase in the number of polyglutamate
(CAG) repeats in the coding sequence of the
Huntington gene located on the short arm of
chromosome 4
• The larger the repeat the earlier the disease appears
• The gene codes for the protein called huntingtin the
function of which is not known
22. HD-Treatment
• Multidisciplinary approach
• Supportive
• Chorea: dopamine blocking agents but associated with
high risk of S/Es
• Depression and anxiety:
• Psychosis: atypical neuroleptics
• Neuroprotective therapy not yet available
23. Sydenham’s Chorea
• Aka St Vitus’ dance
• Disease of children(5-15 yrs)
• More common in females
• Chorea, behavioral disturbances and
occasionally other motor disorders
• 10% of pts with RF
Thomas Sydenham
‘The English Hippocrates
24. Sydenham’s treatment
• Dopamine blocking agents
• Carbamazepine
• Valproic acid
• Steroid
• Prophylactic B.Penicillin
• Risk of recurrence especially with pregnancy (chorea
gravidarum)
25. Other causes of chorea
• Hypo and hyperglycemia
• Hyperthyroidism
• SLE
• HIV
• Polycythemia
• Drugs (cocaine, lithium, CNS stimulants, estrogen,
anticonvulsants)
26. Athetosis
• Slow, distal, writhing, involuntary movements with a
propensity to affect the arms and hands
27. Hemiballismus
• Hemiballismus is a violent form of chorea composed of
wild, flinging, large-amplitude movements on one side
of the body. Proximal limb muscles tend to be
predominantly affected.
• Greek: ballismos= “a jumping about or dancing”
• 100 times rarer than Parkinson’s Disease
28. Hemiballismus
• Both the proximal and distal muscle groups involved
• Hemiballismus often evolves into hemichorea
• The movements may be so severe as to cause
exhaustion, dehydration, local injury, and in extreme
cases, death.
30. Hemiballismus
• Pharmacologic treatment is the same as that
prescribed for other choreatic disorders
• The most widely used agents- Neuroleptics
• Mechanism of action: Dopamine receptor blockage
• Neuroleptics: Typical & Atypical
32. Hemiballismus
• Dopamine depleting agents such as Reserpine and
Tetrabenazine represent another option in the
treatment of chorea
• GABAergic drugs, such as clonazepam, gabapentin and
valproate, can be used as adjunctive therapy.
33. Tics
• Brief ,rapid ,recurrent and seemingly purposeless
stereotyped motor contraction
• Can be suppressed
• Can be motor, vocal, sensory
• Can be simple or complex
34. Tics
• Motor tics- associated muscle movments
• Simple Motor tics: movement only affecting an individual muscle
group
• E.g., blinking, twitching of the nose, jerking of the neck)
• Complex Motor tics: with coordinated involvement of multiple
muscle groups
• E.g., jumping, sniffing, head banging, and echopraxia (mimicking
movements)
35. Tics
• Vocal tics- can also be simple or complex
• Simple- e.g., grunting
• Complex- e.g
• Echolalia- repeating other people's words
• Palilalia- repeating one's own words, and
• Coprolalia- expression of obscene words
• Sensory tics: composed of unpleasant focal sensations
in the face, head, or neck
36. Tics
• Tics may present in adulthood and can be seen in
association with a variety of other disorders, including
PD, HD, trauma, dystonia, drugs (e.g., levodopa,
neuroleptics), and toxins.
37. Tourette syndrome
• Neurobehavioral disorder named after the French
neurologist Georges Gilles de la Tourette
• Predominantly affects males
• Prevalence 0.03-1.6%
• It is thought to be genetic but no specific gene has
been identified
• Alterations in dopamine neurotransmission, opioids, and
second messenger systems are proposed
mechanisms
38. TS- Etiology & Pathophysiology
• TS is thought to be a genetic disorder, but no specific
gene mutation has been identified.
• Current evidence supports a complex inheritance
pattern, with one or more major genes, multiple loci,
low penetrance, and environmental influences.
• The risk of a family with one affected child having a
second is about 25%.
39. TS- Treatment
• Mild cases: education and counseling
• Alpha agonists clonidine, Guanfacine
• Antipsychotics atypical and classical neuroleptics
• Botulinum toxin for focal tics
• DBS targeting the anterior portion of the internal
capsule is under study
40. Myoclonus
• Brief, rapid(<100ms) , shock like, jerky movement
consisting of single or repetitive muscle discharges
• Can be focal ,multifocal, segmental, or generalized
• Can occur spontaneously, with voluntary movements
(action myoclonus), or in response to an external
stimulus(reflex or startle myoclonus)
• Are not suppressible
• Metabolic disturbances (hypocalcaemia, renal failure)
• Negative myoclonus consists of a twitch due to brief
loss of muscle activity as in asterixis
41. Myoclonus
• Essential myoclonus is a relatively benign familial
condition characterized by multifocal lightning-like
movements.
• Myoclonic jerks can be disabling when they interfere
with normal movement.
• They can also be innocent and are commonly observed
in normal people when waking up or falling asleep
(hypnogogic jerks)
42. Myoclonus-Treatment
• Treating the underlying cause or removing the
offending agent
• Pharmacologic therapy: GABAergic agents such as
valproic acid, clonazepam, primidone, levetiracetam
. Treatment is initially directed to the control of any underlying disorder and, if necessary, can often be improved with a beta blocker.
There is no adequate treatment for the cognitive or motor decline. A neuroprotective therapy that slows or stops disease progression is the major unmet medical need in HD. Promitochondrial agents such as ubiquinone and creatine are being tested as possible disease-modifying therapies. Antiglutamate agents, caspase inhibitors, inhibitors of protein aggregation, neurotrophic factors, and transplantation of fetal striatal cells are areas of active research, but none has as yet been demonstrated to have a disease-modifying effect.
From a pathophysiologic viewpoint, the available data suggest involvement of the basal ganglia and cortical structures
* The pathophysiology of TS is not known, but alterations in dopamine neurotransmission, opioids, and second-messenger systems have been proposed. Some cases of TS may be the consequence of an autoimmune response to -hemolytic streptococcal infection [pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection (PANDAS)]; however, this remains controversial
Can occur following cortical , sub cortical and spinal cord pathologies associated with hypoxic damage
