Hyper kinetic movement disorders

1. dystonia

2. • Dystonia is a movement disorder
characterized by sustained or intermittent
muscle contractions causing abnormal, often
repetitive movements, postures, or both;
dystonic movements are typically patterned
and twisting, and may be tremulous.
• Dystonia is often initiated or worsened by
voluntary action.

3. Causes of acquired dystonia
Cerebrovascular
Arteriovenous malformation and aneurysm
Hemorrhage
Ischemia
Brain injury
Brain surgery (including stereotactic ablations)
Electrical injury
Head trauma
Medication
Antiseizure medications
Calcium channel blockers
Dopamine agonists
Dopamine receptor blocking agents, including antipsychotic drugs
and metoclopramide
Levodopa
Infection
Encephalitis lethargica
Human immunodeficiency virus (HIV) infection
Subacute sclerosing panencephalitis
Syphilis
Tuberculosis
Viral encephalitis

4. Neoplastic and paraneoplastic
Brain tumor
Paraneoplastic or autoimmune encephalitis
Toxic
3-nitropropionic acid
Carbon disulfide
Cobalt
Cyanide
Disulfiram
Manganese
Methanol
Psychogenic (functional)

5. • Dystonia can be inherited, acquired, and idiopathic.
• Both degenerative and nondegenerative causes of
dystonia exist.
• The pathogenesis of most forms of isolated dystonia is
largely unknown.
• There are no consistent neuropathologic features.
• Multiple brain areas may be involved, including basal
ganglia, motor cortex, supplementary motor areas,
cerebellum, and their connections.
• Abnormalities in dopaminergic and cholinergic
neurotransmitter systems may play a role.

6. • Dystonia is classified based upon clinical
characteristics and etiology.
• Important clinical characteristics are age at
onset, body distribution (ie, focal, segmental,
multifocal, generalized, or hemidystonia),
temporal pattern, and associated features (eg,
isolated dystonia or dystonia combined with
another movement disorder).

7. • Early-onset isolated dystonia
• Early-onset isolated dystonia presents in
childhood or young adulthood.
• It most often begins with symptoms in the limbs,
typically the leg, often as intorsion of the foot.
• It spreads to other body areas to become
generalized in over 50 percent, usually within five
years of onset.
• Cases may be inherited/genetic or idiopathic.

8. • Adult-onset focal dystonias
• Adult-onset focal or segmental isolated dystonias
may involve different body areas and extend to
contiguous regions, but progression to
generalized dystonia is rare.
• Onset is usually after age 30 years.
• Most cases are idiopathic.
• Common and/or important types include cervical
dystonia, blepharospasm, and task-specific
dystonias.

9. • Combined dystonias
• Combined dystonias are those in which
dystonia is combined with other movement
disorders, such as parkinsonism or myoclonus.
• These are sometimes accompanied by
pyramidal tract involvement and/or nonmotor
features, including cognitive decline.
• Many are inherited.

10. Isolated dystonias
Early-onset generalized isolated dystonia
Description: dystonia with focal onset beginning in childhood that often
progresses to generalized involvement; cases may be sporadic, familial,
genetically defined, or without known cause
Early-onset generalized dystonia (DYT-TOR1A)
Adolescent-onset dystonia of mixed type (DYT-THAP1)
Focal or segmental isolated dystonia with onset in adulthood
Description: focal or segmental isolated dystonias usually begin after age 30
years; most are sporadic without identifiable cause, and rarely progress to
generalized dystonia, but can extend to contiguous body regions
Adult-onset segmental dystonia (DYT-GNAL)
Cervical dystonia
Blepharospasm
Writer's cramp
Oromandibular dystonia
Laryngeal dystonia (spasmodic dysphonia)
Limb dystonia
Other syndromes of late adult-onset focal isolated dystonia

11. Combined dystonias
Dystonia-parkinsonism
Description: disorders that combine dystonia and parkinsonian features, sometimes accompanied by pyramidal
tract involvement, and/or nonmotor features, including cognitive decline; many are inherited
Dopa-responsive dystonia (DYT-GCH1, DYT-TH, and DYT-SPR)
Wilson disease
Early-onset parkinsonism (PARK-PARKIN)
Early-onset parkinsonism (PARK-PINK1)
Early-onset parkinsonism (PARK-DJ1)
X-linked dystonia-parkinsonism/Lubag (DYT-TAF1)
Rapid-onset dystonia-parkinsonism (DYT-ATP1A3)
Neurodegeneration with brain iron accumulation:
Pantothenate kinase-associated neurodegeneration (PANK2 gene)
Infantile neuroaxonal dystrophy (PLA2G6 gene)
Mitochondrial membrane protein-associated neurodegeneration (C19ORF12 gene)
Beta-propeller protein-associated neurodegeneration, also known as static encephalopathy of childhood with
neurodegeneration in adulthood (WDR45 gene)
Fatty acid hydroxylase-associated neurodegeneration (FA2H gene)
Kufor-Rakeb syndrome (PARK-ATP13A2)
Neuroferritinopathy (FTL gene)
Aceruloplasminemia (ceruloplasmin gene)
Woodhouse-Sakati syndrome (DCAF17 gene)
Myoclonus-dystonia
Description: disorders in which there is a combination of dystonia and myoclonus; dystonia may be mild, and
myoclonus generally predominates
Myoclonus-dystonia (DYT-SGCE)
Paroxysmal dyskinesia with dystonia
Description: disorders characterized by episodes of spontaneous or induced dyskinesia with dystonia
Paroxysmal nonkinesigenic dyskinesia (DYT-MR1)
Paroxysmal kinesigenic choreoathetosis (DYT-PRRT2)
Paroxysmal exertion-induced dyskinesia (DYT-SLC2A1)

12. • The diagnosis of dystonia is mainly clinical.
• Expert observation by a movement disorder specialist is suggested
to confirm the diagnosis of dystonia in cases where there is
uncertainty or confusion.
• Atypical presentations and/or suspicion for secondary etiologies
should prompt further investigations.
• •Role of levodopa trial –
• For patients with focal or generalized dystonia of unknown
etiology, a trial of levodopa should be performed to suggest or
exclude the diagnosis of dopa-responsive dystonia (DRD).
• •Genetic testing –
• Genetic testing for TOR1A is recommended for patients with early-
onset dystonia, or those with late onset who have an affected
relative with early-onset dystonia.

13. Clinical features of isolated dystonia
Presence of:
Sustained involuntary movement, sometimes overlying spasms
Consistent directional quality
Involves same body region(s)
Enhanced or produced by activity of involved area
Varies with change in activity or posture
Sensory tricks (geste antagoniste) may reduce symptoms
May have associated tremor
Absence of:
Weakness
Amyotrophy
Spasticity
Ataxia
Ocular abnormalities
Abnormal eye movements
Retinal changes
Clinical
features
of
isolated
dystonia

14. Pseudodystonias
Atlantoaxial subluxation
Syringomyelia
Arnold-Chiari malformation
Head tilt due to trochlear nerve palsy
Vestibular torticollis
Posterior fossa mass
Soft tissue neck mass
Congenital muscular torticollis
Congenital Klippel-Feil syndrome
Isaacs syndrome
Sandifer syndrome
Satoyoshi syndrome
Stiff-person syndrome
Camptocormia
Scoliosis
Ventral hernia
Trigger finger

15. symptomatic treatment of dystonia in adults

16. Children and adolescents
• Levodopa trial –
• For children with idiopathic focal or generalized
dystonia, we recommend a trial of levodopa to
confirm or exclude the diagnosis of dopa-
responsive dystonia (DRD).
• Symptomatic therapy –
• Children with multifocal or generalized isolated
dystonia who do not respond to levodopa can be
treated with other oral medications, botulinum
toxin (BoNT) injections, or deep brain stimulation
(DBS) in refractory cases:

17. • Oral medications –
• For most children and adolescents with
debilitating generalized isolated dystonia that
does not respond to a trial of levodopa, we
suggest initial treatment with an
anticholinergic drug such as trihexyphenidyl.
• Second-line oral therapies
include baclofen and benzodiazepines.

18. • Role of BoNT injections –
• For children and adolescents who have
debilitating multifocal or generalized isolated
dystonia that does not respond to pharmacologic
treatment, and for those with focal dystonia, we
suggest BoNT injections of selected muscles that
are most troublesome.
• However, widespread injections are not a
reasonable option for multifocal or generalized
dystonia.

19. • Surgical options –
• For children with debilitating isolated dystonia
who do not respond to pharmacologic therapy
or BoNT injections, we suggest referral to a
multidisciplinary movement disorders clinic
for consideration of bilateral DBS of the
internal globus pallidus (GPi).

20. Adults
• Role of levodopa trial –
• Although adult onset of DRD is atypical, we suggest a levodopa trial
for most adults with idiopathic focal or generalized dystonia.
• However, there is no consensus regarding a trial of levodopa for
adults in this setting.
• ●Cervical dystonia –
• BoNT injections are the mainstay of therapy for cervical dystonia.
• Oral medications are used in patients who cannot receive injections
and for those with an inadequate response to first-line therapy.
• ●Other focal dystonias –
• For adults with blepharospasm, focal upper limb dystonia
(including writer's cramp), and adductor spasmodic dysphonia
(adductor laryngeal dystonia), we recommend BoNT injection
therapy .

21. • Role of oral medications –
• Symptomatic medication trials play a role in adults with generalized
dystonia and those with focal dystonias who do not have access to
BoNT therapy.
• •For most adults with refractory generalized dystonia, we suggest
first-line therapy with a benzodiazepine such as clonazepam.
• Low doses of trihexyphenidyl or baclofen are alternative second-
line therapies.
• •A vesicular monoamine transporter type 2 (VMAT2) inhibitor such
as tetrabenazine may be beneficial for adults with debilitating
generalized isolated dystonia, although careful monitoring for side
effects, including depression, is necessary.

23. • Refractory dystonia –
• For adults with debilitating generalized
dystonia or other types of focal/segmental
isolated dystonia who do not respond to oral
pharmacologic therapy or BoNT injections, we
suggest referral to a multidisciplinary
movement disorders clinic for consideration of
bilateral DBS of the GPi.