Dystonia

APPROACH TO DYSTONIA
Dr Zuber Quazi
Senior Resident
Neurology

Worldwide, the prevalence of DYSTONIA
is estimated to be 16.4 / 100,000
Rajan R, Srivastava AK,
Anandapadmanabhan R, Vibha D, Pandit AK, Prasad
K. Clinical spectrum of dystonia in a tertiary care
movement disorders clinic in India. Ann Mov Disord
2018;1:49-53.
A community study on DYSTONIA from India has
reported CPR of Primary Dystonias was 43.91 /
100,000. Mean onset of dystonias was earlier in
women (43.5 years) when compared to men (46.6
years).
The study on primary dystonia showed higher
prevalence when compared with that of many studies
globally and more cases of limb dystonias than
blepharospasm and cervical dystonias in western
reports. [29]
Secondary Dystonia was less common (CPR-11.45
/ 100,000) and usually due to sequel to encephalitis,
drug and stroke. [29]
Clinic based study has shown infections, hypoxia, trauma
and kernicterus as common causes of secondary
dystonias. [31]
Das SK, Ghosh B, Das G, Biswas A, Ray J. Movement
disorders: Indian scenario: A clinico-genetic review.
Neurol India 2013;61:457-66
Estimated Prevalance of Generalised Dystonia
Worldwide is 1.4 per 1,00,000
Bradley and Daroff’s Neurology in Clinical Practice 8th
Edition
Epidemiology of Dystonia

Brachial (65.8%), followed by
cranial (27.1%) and
cervical (15.7%).
Task specificity was documented in 51.2%
of focal dystonias, all brachial dystonias.
Rajan R, Srivastava AK, Anandapadmanabhan R, Vibha D, Pandit AK, Prasad K. Clinical
spectrum of dystonia in a tertiary care movement disorders clinic in India. Ann Mov
Disord 2018;1:49-53.

• “dystonia musculorum deformans” -- by Oppenheim 1911;
• Klein and Fahn (2013) ---coined the term DYSTONIA.
• “Sustained muscle contractions
• Cause twisting and repetitive movements or abnormal
postures̄”
– Slow and sustained
– Rapid and intermittent
– Patterned
• Other Helpful Feature
– Often initiated or worsened by voluntary action
– Overflow to nearby muscles
– Sensory trick
• Bradley Neurology in clinical practice 8th edition
• Albanese et al., 2013
• Scientific Advisory Board of the Dystonic Medical
Research Foundation

CONTINUUM 2019;25 (4, MOVEMENT DISORDERS):976–1000.

Classification a/c To Body Distribution

Classification a/c To Body Distribution
Marsden’s Book of Movement Disorders

Primary Dystonia
• Primary or Idiopathic dystonias in which
dystonia is the major neurological feature
• And it is not caused by other recognized
diseases.
• The most important of these is Primary
Generalized Dystonia, which is also called
“Idiopathic Torsion Dystonia” or “Dystonia
musculorum deformans”.

Classification Primary Dystonia

Clinical Features Favouring
Primary Dystonia

Red flag For GENETIC etiology (in History)
Forman EB, et al. Arch Dis Child Educ Pract Ed 2020;0:1–7

Algorithm for diagnosis of Hereditary Dystonias

 Childhood and Adolescence generally progress to develop
generalized or segmental disease.
 Adult life usually remain as focal dystonia, (rarely segmental or
generalized).
 PRIMARY DYSTONIAS often first affect the legs in children and
adolescents, whereas this is extremely uncommon in adults.
 Cranial / Cervical onset ------ Adults
 In Children ------Cranial or cervical onset (occurring in no more
than 7 %)
 Progression to GENERALIZED DYSTONIA:-
60 % of Childhood-onset
25 % of Adolescent-onset
3 % of patients with Adult onset.
Features of Primary Dystonia

Clinical Features Favoring Secondary Dystonia
 Sudden onset and rapid Progression
 Onset in Infancy
 Cranial onset in childhood
 Restriction to focal or segmental dystonia with childhood onset
 Onset in Legs in adult
 Progression to generalized dystonia with Adult onset
 Prominent orobulbar involvement
 Hemidystonia
 Fixed spasm
 Other Neurological or systemic signs

Acquired causes of Dystonia
Forman EB, et al. Arch Dis Child Educ Pract Ed 2020;0:1–7
Albanese et al 2019 Dystonia: diagnosis and management

Acquired Causes of Dystonia
Pathophysiology Etiology
Dystonic cerebral palsy Perinatal Brain injury
Drug Induced Neuroleptics, Dopamine blockers,
Anticonvulsant, Calcium Channel blockers
Toxic Heroin inhalation, Methanol, Carbon
Monoxide, Disulfiram, Cyanide, Manganese,
Cobalt.
Brain lesion Ischemic, hemorrhagic, AVM, Neoplasm,
Radiotherapy, Head trauma, Brain surgery,
Electrical injury
Infection Viral Encephalitis, SSPE, HIV, Prion disease
Immune mediated ADEM, Paraneoplastic encephalitis
Metabolic Hypoglycemia, HHS, Hypocalcemia,
Hypoparathyroidism, Hyperthyroidism,
Uremia

• Buccolingual Crisis - trismus, risus sardonicus, dysarthria,
dysphagia, grimacing, tongue protrusion.
• Oculogyric Crisis - spasm of the extraocular muscles, most
commonly deviated upward.
• Torticolic Crisis - abnormal asymmetric head or neck
position.
• Tortipelvic Crisis - abnormal contractions of the abdominal
wall, hip, and pelvic musculature.
• Opisthotonic Crisis - characteristic flexion posturing with
arching of the back
• Laryngeal Dystonia - dysphonia, stridor
• Pseudomacroglossia - patient describes the sensation of
tongue swelling and protrusion.

Characteristics of Dystonia
Dystonic postures
Muscle contractions may be continuous, forcing
limbs and trunk into sustained postures
A body part is flexed or twisted along its
longitudinal axis
Slowness and clumsiness for skilled movements are
associated with sensation of rigidity and traction in
the affected part

Dystonic movements
Movements are repetitive and patterned (i.e.,
consistent and predictable) or twisting
Sustained at their peak

Gestes antagonistes “sensory tricks”
Are voluntary actions performed by patients that reduce or
abolish the abnormal posture or the dystonic movements
Simple movements
These movements are natural and graceful, not consisting
in forceful opposition to the phenomenology of dystonia
does not push or pull the affected body part, but simply
touches it (“sensory trick”) or accompanies it.
Alleviation of dystonia occurs during the geste movement,
usually soon after its start

Other Sensory Tricks
• Touching the chin or the lips, applying
pressure beneath the chin, or placing a object
in the mouth- Oromandibular Dystonia
• Touching the affected hand with the other
hand- Writer's Cramp
• Leaning against the wall while standing,
pressing on the hips or applying pressure to
the back – Truncal Dystonia

Mirror Movements
• It refers to the involuntary movements on one side of the
body, which mimic voluntary movements of the opposite
side of the body through the activation of homologous
muscles that approach the performance (i.e., mirror) of a
specific task.
• E.g.; Involuntary movement of Right UL when writing with
left hand in a Right handed person suffering from Writer’s
cramp.
Cox BC, Cincotta M, Espay AJ. Mirror movements in movement disorders. Tremor Other Hyperkinet Mov 2012;2:
http://tremorjournal.org/article/view/59

Overflow
• Overflow is defined as the extension of muscle
contraction into an adjacent area anatomically
distinct from the primary movement when
dystonic posture reaches a peak.
• A voluntary compensatory posturing may not
easily be distinguishable from overflow.
• Usually, voluntary movements are slower and
more variable.
• According to Hallett, overflow is the clinical
representation of impairment of normal
surrounding inhibition present in dystonia.

LATEROCAPUT
I/L SCM
I/L Splenius capitis
I/L Trapezius
Movement Disorders Clinical Practice, Volume: 2, Issue: 3, Pages: 224-226, First published: 07 May 2015, DOI: (10.1002/mdc3.12172)

LATEROCOLLIS
I/l SCM
I/l Splenius capitis
I/l Levator scapulae
I/l Trapezius

TORTICAPUT
C/L SCM
C/L Trapezius
C/L Splenius capitis
I/L Oblique Capitis
inferior

TORTICOLLIS
C/l SCM
C/l Trapezius
I/l Splenius capitis
I/l Levator scapulae

ANTECAPUT
B/L Longus Capitis
B/L Levator Scapulae
B/L SCM

ANTECOLLIS
B/L SCM
B/L Longus colli
B/L Scalenus

RETROCAPUT
B/L Oblique Capitis
Inferior
B/L Semispinalis Capitis
B/L Trapezius
B/L Splenius Capitis

RETROCOLLIS
B/L SCM
B/L Longus colli
B/L Scalenus

SHIFT
Combination of
ANTEROCOLLIS and
RETROCAPUT

Blepharospasm
• Photophobia (common); other eye
problems (i.e, blepharitis, iritis, corneal
disease, or conjunctivitis);
• Eyelid opening apraxia (rare)
• Stereotyped bilateral and synchronous
orbicularis oculi spasms inducing
narrowing/closure of the eyelids;
• Increased blinking rate

Spasmodic Dysphonia
• Focal Laryngeal Dystonia Associated
with onset or worsening specific to volitional
speech activity (i.e. task specific)
• Affects 1 per 100,000 dystonia cases.
• Less than 8% of those with SD have family
members with dystonia

LARYNGEAL DYSTONIA
• Idiopathic onset
• Onset typically occurs during mid-life ages of 30-
50 years of age
• Women are more often affected than men (4:1
ratio)
• Progression is steepest during first year and is
chronic thereafter
• Normal vegetative voice function-----Laughing,
Crying, Cough, Yawn, Whisper, Respiration

Limb Dystonia
• Cramping of feet; toe curling;
• Involuntary foot/leg/hip movements
• Leg movements including stamping movements,
toe tapping, and rapid alternating movements
(heel/toe);
• Torsion in limb as well as overflow;
• Movements may be slow but will not diminish in
amplitude;
• Symptoms improve when walking backward

Non Motor Symptoms
 Mild Neck Discomfort preceding Cervical Dystonia,
 Irritation or dry eyes Blepharospasm,
 Throat Irritation heralding the onset of Spasmodic
Dysphonia
 Pain
Cervical Dystonia(70%)
Focal Hand Dystonia or Writer’s Cramp (30%).
 Neuropsychiatric Abnormalities,
frequent in Cervical Dystonia, Blepharospasm, Laryngeal
Dystonia And Focal Hand Dystonia.
 Cognitive Abnormalities
 In Isolated Dystonia ----- NO cognitive abnormalities;
Combined Dystonia (whether inherited or idiopathic)
syndromes ----Frequent Cognitive abnormalities

Investigations
Blood
• Thyroid function test
• Creatine kinase
• Glucose
• Acylcarnitine
• Very long chain Fatty acids
CSF
• Glucose
• Lactate
• Amino acid
Urine
• Creatine
• Organic acids
• Purines
• Pyrimidines

• Metabolic and blood testing
– acanthocytes,
– ceruloplasmine,
– serum and urinary copper, uric acid,
– serum pyruvate and lactate levels
– slit-lamp examination.
Investigations

• MRI brain
– show accumulation of metals:
• MANGANESE, as in Kufor Rakeb syndrome (PARK-
ATP13A2)
• CALCIUM, as in primary familial brain calcifications
• IRON, as in neurodegenerations with brain iron
accumulation
• CT scan
– if calcifications are suspected
Investigations

EMG
• EMG features observed in dystonia are:
1. prolonged bursts (200-500 ms),
2. simultaneous contractions (co-contraction) of
agonist and antagonist muscles,
3. involuntary activation of contiguous muscles
(overflow) i.e., contraction of surrounding
muscles through impaired inhibition of spinal
and medulla reflexes

Differences between Dystonia and Spasticity
DYSTONIA SPASTICITY
Definition Sustained /intermittent
muscle contractions l/t
twisting and repititive
movements, abnormal
postures or both
Hypertonia with one / both
of following
1. Resistance passive
movement increases with
speed and varies with
direction of movement
Relation to Velocity Not dependent Dependent
Triggers Emotion, pain, voluntary
action, stress, illness,
prolonged exertion, fatigue
or fasting
Movement/ passive stretch
Sleep Relieved Persistent
Extensor toes Occurs spontaneously
‘Striatal toe’
Babinski response
Additional Features Extrapyramidal signs UMN signs
Rating scale Burke-Fahn Marsden Modified Ashworth

Mimickers of Craniocervical Dystonia
Retropharyngeal Abscess
Atlanto-axial subluxation
Congenital Muscular Torticollis
Ocular Torticollis ( head tilt ; cranial nerve palsy
ICSOL in posterior fossa
Sandifer syndrome with head tilt
Dropped head syndrome ( NMj disorders)

Mimickers of Limb Dystonia
Contracture
Spasticity
Abnormal posture due to paresis or atrophy
Myotonia or Neuromyotonia
Stiff person syndrome
Tonic spasm
Seizures

Mimickers of Facial Dystonia
Ptosis
Trismus
Hemimasticatory spasm
Myotonia
Tetanic Spasm
Apraxia of eyelid opening

Acute Dystonic Reaction
• Involuntary contractions of muscles of the extremities, face,
neck, abdomen, pelvis, or larynx in either sustained or
intermittent patterns that lead to abnormal movements or
postures.
• Symptoms - Reversible or Irreversible
• Can occur after taking any dopamine receptor-blocking agents.
• occur shortly after the initiation of an offending agent or an
increased dose of a possible offending agent.
• Anticholinergic agents and benzodiazepines are the most
commonly used agents to reverse or reduce symptoms in acute
dystonic reaction.
• Acute dystonic reactions are often transient but can cause
significant distress to the patient.
• Although rare, laryngeal dystonia can cause life-threatening
airway obstruction.

Causative Agents
• Antipsychotic and antiemetic agents (mc)
• Anti-malarial, antidepressants, antihistamines,
and anticonvulsants
• First-generation antipsychotics haloperidol ---
higher risk.
• Second-generation antipsychotics --reduced risk
• Metoclopramide and Prochlorperazine
• Methylphenidate, Albendazole, Chloroquine,
Rivastigmine, and Foscarnet

Treatment Of Acute Dystonic Reactions
• Diphenhydramine
• 50 mg intravenous (IV) in adults and 1 mg/kg
up to 50mg IV in pediatric patients.
• To prevent recurrence ---- every 6 hours for 1
to 2 days

• Benztropine ---- single dose of 1 to 2 mg IV
stat followed by 1 to 2 mg by PO BD ×7 days to
prevent a recurrence.
• Benzodiazepines----for patients that fail to
respond completely to anticholinergic therapy.
– IV or IM lorazepam at 0.05 to 0.10 mg/kg or IV
diazepam at 0.1 mg/kg may be considered.

Differential Diagnosis of Dystonic Storm
Entity Age Trigg
er
Time
cours
e
Pheno
menolo
gy
Othe
r
sign
s
Alter
ed
Ment
al
statu
s
Auto
nomi
c
Stabi
lity
Dystonic Storm P +/- Hours-
Days
Dystonia
+/- chorea
-
- +
Neuroleptic
malignant
syndrome
A +++ Days-
Weeks
Parkinsoni
sm
- + +
Malignant
hyperthermia
All +++ Acute - - - -
Delirium tremens A +++ Acute Myoclonus Psychos
is
+ +
Autoimmune
encephalitis (e.g.
anti-NMDA)
P-YA - Days-
Weeks
Chorea Psychos
is
+ +

Dystonic tremor vs Essential Tremor
• Dystonic tremor is distinguished from other
tremor types by the presence of a NULL
POINT
• Neutral position at which tremor Disappears.
• Affected area is placed in the maximum
direction of the pull
• Position of the head and neck when the head
tremor diminishes or resolves as the head and
neck are allowed to assume the maximal
dystonic position.
• (Jankovic J, Hallett M, Okun MS, Comella CL, Fahn S. Principles and Practice of Movement Disorders. 3rd ed. Philadelphia, PA:
Elsevier; (2021).

Pseudoathetosis Dystonia
Involuntary, slow,
writhing movements of
the digits and distal
extremities occurring
with the eyes closed
Sustained muscle
contractions Causing
twisting and repetitive
movements or abnormal
postures
Occurs due to Impaired
Proprioception
No Sensory loss
Pseudoathetosis and Dystonia

Fixed Dystonia
• Fixed Dystonia Was Defined As Immobile Dystonic Postures
That Did Not Return To The Neutral Position At Rest;
• Limb Onset Is Most Frequent

• Focal ( In Some ), Progressive ( In Majority)
• Pain
• Lack Of Sensory Tricks
• Lack Of Action-specificity
• Lack Of Response To Traditional Treatment For
Dystonia
• Overlaps With CRPS And Psychogenic/
Somatoform Disorder.

The Global Dystonia Severity Rating
Scale

DBS
• Postero ventral lateral portion of the globus pallidus interna (GPi) is
the most commonly used target site for DBS.
• Atlas-based co-ordinates for GPi are 19-22 mm lateral and 2 mm
anterior from MCP and 4 mm ventral to AC/PC line[33] [Figure 2].
• Other targets such as STN, thalamus and cerebellum have been
used with varying success.[40],[41],[42] These may have a role
depending upon the type of dystonia being treated.
• A retrospective cohort study evaluating 14 patients with GPi-DBS
and 16 with STN-DBS found the former better for alleviating axial
symptoms (93% vs 83% improvement in the axis sub score of
BFMDRS).
• On the other hand, STN-DBS warranted lesser delivery of electrical
energy ((124 ± 52 vs 192 ± 65 μJ) which led to lesser battery
consumption.

Anatomy (in orange) superimposed on the patient's axial (a) and coronal
(b) T2W image, depicting the GPi target on the right (blue trajectory)
and left (yellow trajectory)

References
• Bradley Neurology in clinical practice 8th edition
• Marsden’s Book of Movement Disorders
• Albanese et al 2019 Dystonia: diagnosis and management
• Albanese et al., 2013 Phenomenology and classification of
Dystonia : A Consensus and update
• Scientific Advisory Board of the Dystonic Medical Research
Foundation
• CONTINUUM 2019;25 (4, MOVEMENT DISORDERS):976–1000
• Forman EB, et al. Arch Dis Child Educ Pract Ed 2020;0:1–7
• Movement Disorders Clinical Practice, Volume: 2, Issue: 3,
Pages: 224-226, First published: 07 May 2015, DOI:
(10.1002/mdc3.12172)

Dystonia

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Dystonia

Similar to Dystonia (10)

More from NeurologyKota

More from NeurologyKota (20)

Recently uploaded

Recently uploaded (20)

Dystonia