This presentation focuses on clinical approach to dystonia , based on latest recommendation by MDS and other articles . Comments and criticism are highly welcome .

1. APPROACH TO DYSTONIA
Dr Srimant Pattnaik
DM PDT
BIN , Kolkata

3. Circuit

4. Summary
Pathway Receptor Net output Disease related
Direct D1 Excitatory Hypokinesia
Indirect D2 Inhibitory Hyperkinesia

15. DYSTONIA

17. Definition of Dystonia(2013)
• 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,
twisting, and may be tremulous.
• Dystonia is often initiated or worsened by
voluntary action and associated with overflow
muscle activation.

18. Mechanism
• Repeated Co-contraction of agonist and
antagonist group of muscle produces the
typical twisting or sustained movement in
dystonia

19. Various classical terms
• Athetotic dystonia myoclonic dystonia
• <seconds – dystonic spasm
• Several seconds : dystonic movements
• Minutes to hours : dystonic postures
• Weeks or longer : contractures

20. Motor phenomenology relevant to
dystonia
• Voluntary action
• Patterning
• Null point
• Dystonic tremor
• Overflow
• Mirror dystonia
• Alleviating maneuvers

21. Voluntary action
• Purposeful, anticipated, goal-directed
movement produced by will.
• Dystonia is typically influenced by voluntary
movement or voluntarily maintained posture.

22. Patterning
• When dystonic contractions are sustained,
they produce twisted or abnormal postures.
• These postures have a characteristic
directionality, referred to as patterning

23. Dystonic tremor
• A spontaneous oscillatory, rhythmical, although
often inconstant, patterned movement produced
by contractions of dystonic muscles often
exacerbated by an attempt to maintain primary
(normal) posture.
• The amplitude of dystonic tremors is enhanced
when the affected area is positioned against the
direction of the pull (ie, turning the neck to the
right in a patient with left cervical dystonia).

24. • Likewise, dystonic movements may subside
when the affected area is placed in the maximum
direction of the pull.
• This placement is identified as the null point
• Dystonia with tremor is a different entity which is
defined as a tremor unrelated to the dystonic
muscles
• Dystonic tremor may be difficult to distinguish
from essential-type tremor

26. Overflow
• unintentional muscle contraction which
accompanies, but is anatomically distinct from
the primary dystonic movement.
• It commonly occurs at the peak of dystonic
movements

27. Mirror dystonia
• Mirror dystonia is a unilateral posture or
movement that is the same or similar in
character to a dystonic feature that can be
elicited, usually in the more severely affected
side, when contralateral movements or
actions are performed.

28. Alleviating maneuvers (sensory tricks or gestes
antagonistes)
• Voluntary actions that specifically correct the
abnormal posture or alleviate the dystonic
movements.
• These are usually simple graceful movements
(“gestes”) involving, or directed to, the body
region affected by dystonia, but not consisting
in a forceful opposition to the phenomenology
of dystonia.

29. Is dystonia a purely motor
phenomenon ?
• existence of a primary deficit in sensory input
and processing in primary dystonias(pain,
sensory trick)
• depression appears to represent an important
feature of primary dystonia
• Non motor symptom need to be taken care of
in order to improve quality of life

30. Approach
• The very first question that should be asked
while approaching a case of dystonia is
• Is it really dystonia , or a mimicker?

31. Pseudo dystonia
• Dystonic (tonic) tics
• Head tilt (vestibulopathy,
trochlear nerve palsy)
• Bent spine,
camptocormia, scoliosis
• Atlanto axial and shoulder
subluxation
• Arnold-Chiari
malformation
• Soft tissue neck mass
• Congenital muscular
torticollis
• Congenital Klippel-Feil
syndrome
• Satoyoshi syndrome
• Dupuytren’s contractures
• Trigger digits
• Neuromuscular causes
(Isaacs syndrome, etc.)
• Spasms (hypocalcemia,
hypomagnesemia,
alkalosis)
• Orthopedic and
rheumatological causes
• Sandifer syndrome
• Deafferentiation
(pseudoathetosis)

32. Classification

33. Need for a new classification?

34. Current classification of dystonia
(2013)
• Axis I: clinical features
• Axis II: etiology
• Done by a panel of experts in the field, hence
called a consensus.

35. Axis I
• Age at onset
• Body part involved
• Temporal sequence
• Associated features

36. Age at onset
• Infancy (birth to 2 years)
• Childhood (3–12 years)
• Adolescence (13–20 years)
• Early adulthood (21–40 years)
• Late adulthood (>40 years)

37. Body distribution
• Focal
• Segmental
• Multifocal
• Hemidystonia
• Generalized

38. Body regions
• Upper cranial region
• Lower cranial region
• Cervical(includes shoulder)
• Larynx
• Trunk
• Upper limb
• Lower limb

39. Focal dystonia
• Affects one body region
– Blepharospasm
– Oromandibular(jaw opening/jaw closing)
– Lingual
– Cervical
– Laryngeal(adductor/abductor)
– Writer’s cramp
– Hemifacial spasm is not a dystonia

40. Segmental Dystonia
• The abnormal movements affect two or more
contiguous body parts (for example, the armand neck)
i. Craniocervical dystonia: A combination of
blepharospasm as well as oromandibular, lingual,
facial, laryngeal, and cervical dystonia
ii. Brachial: One or both arms with or without the
involvement of neck or cranial muscles are involved
iii. Crural: One leg plus trunk, or both legs are involved
iv. Axial: Neck and trunk with or without cranial muscles
are involved.

41. Multifocal dystonia: Two or more noncontiguous
body areas are involved (for example, the right
arm and the left leg)
Hemidystonia: Affects one side of the body
Generalized dystonia: Involves two or more
contiguous body parts in addition to the
trunk.

42. Temporal pattern
• Disease progression
– Static
– Progressive
• Disease variability
– Persistent. Dystonia that persists to approximately the same
extent throughout the day.
– Action-specific. Dystonia that occurs only during a particular
activity or task.
– Diurnal fluctuations. Dystonia fluctuates during the day, with
recognizable circadian variations in occurrence, severity and
phenomenology.
– Paroxysmal. Sudden self-limited episodes of dystonia usually
induced by a trigger with return to pre-existing neurological
state.

43. Associated features
• Isolated
– With tremor
– Without tremor
• Combined
– Other movement disorder
– Other neurological features
– Systemic features

44. Axis II
• Nervous system pathology
• Inherited vs Aquired

45. Nervous system pathology
• Evidence of neurodegeration
( gross/microscopic/molecular )
• Evidence of structural lesion
• Neither

46. Inherited or Acquired
• Inherited
– AD
– AR
– XR
– mt
• Acquired
– Perinatal brain injury
– Infection
– Drug
– Toxic
– Vascular
– Neoplastic
– Brain injury
– Psychogenic
•Idiopathic
Sporadic
Familial

47. Acquired causes
• Perinatal brain injury: dystonic cerebral palsy, delayed-
onset dystonia;
• Infection: viral encephalitis, encephalitis lethargica,
subacute sclerosing panencephalitis, human
immunodeficiency virus (HIV) infection, other (tuberculosis,
syphilis, etc.);
• Drug: levodopa and dopamine agonists, neuroleptics
(dopamine receptor blocking drugs), anticonvulsants, and
calcium channel blockers;
• Toxic: manganese, cobalt, carbon disulfide, cyanide,
methanol, disulfiram, and 3-nitropropionic acid;
• Vascular: ischemia, hemorrhage, and arteriovenous
malformation (including aneurysm);
• Neoplastic: brain tumor, and paraneoplastic encephalitis;
• Brain injury: head trauma, brain surgery (including
stereotactic ablations), and electrical injury;
• Psychogenic (functional).

49. Pitfalls in new classification
.Psychogenic dystonia is included in etiology
.pseudo dystonia not clearly defined

51. Isolated dystonia
• Isolated genetic dystonia
• Isolated idiopathic dystonia of adulthood
• Isolated dystonia syndromes with red flags

52. Genetic dystonia

53. Isolated genetic dystonia

54. Idiopathic adult dystonias
• Task specific
– Writer’s cramp
– Musician’s hand
• Cranial
– Upper cranial : Blepharospasm
– Lower cranial : Oromandibular , lingual
– Laryngeal : Abductor & Aduuctor type
• Cervival

55. Cervical dystonias: head
position

56. Red flags against a diagnosis of idiopathic dystonia
• Unusual pattern of clinical manifestations with regard to
the age at onset and distribution
• Sudden onset of symptoms with rapid progression
• History of perinatal birth injury or developmental delay
• Exposure to drugs (such as dopamine receptor blockers)
• Presence of other neurological or systemic signs (which
would indicate combined dystonia)
• Prominent bulbar involvement with tongue protrusion and
dysphagia
• Hemidystonia (which is indicative of structural lesions
causing dystonia)
• Fixed dystonia (which is indicative of psychogenic dystonia)

57. Combined dystonia
• Dystonia +/− parkinsonism of infantile or childhood onset
• Dystonia +/− parkinsonism of adolescent and young adult onset
• Dystonia and parkinsonism in older adults
• Dystonia with spasticity (+/− parkinsonism)
• Dystonia with cerebellar ataxia
• Dystonia with myoclonus
• Dystonia as part of paroxysmal dyskinesia
• Dystonia with chorea
• Dystonia with tics
kindly see Supplementary material of the article ASSESSMENT OF THE
PATIENT WITH ISOLATED OR COMBINED DYSTONIA: AN UPDATE ON
DYSTONIA SYNDROMES Fung et al Mov Disord. 2013 Jun 15; 28(7): 889–898.
for list of diseases with above sydtonia syndrome

58. Dystonia as part of paroxysmal dyskinesia

59. Dystonia with other neurological
involvement
• Dystonia with deafness
• Dystonia with ophthalmological abnormalities
• Dystonia with peripheral neuropathy
• Dystonia with progressive dementia
kindly see Supplementary material of the article ASSESSMENT OF THE
PATIENT WITH ISOLATED OR COMBINED DYSTONIA: AN UPDATE ON
DYSTONIA SYNDROMES Fung et al Mov Disord. 2013 Jun 15; 28(7): 889–898.
for list of diseases with above sydtonia syndrome

60. Dystonia with systemic disease
• Dystonia with endocrine abnormalities
• Dystonia with hematological abnormalities
• Dystonia with with solid organ involvement
kindly see Supplementary material of the article ASSESSMENT OF THE
PATIENT WITH ISOLATED OR COMBINED DYSTONIA: AN UPDATE ON
DYSTONIA SYNDROMES Fung et al Mov Disord. 2013 Jun 15; 28(7): 889–898.
for list of diseases with above sydtonia syndrome

62. Syndromes according to brain imaging
• Dystonia with MRI evidence of neuronal brain
iron accumulation
• Dystonia with basal ganglia lesions
• Dystonia with leucoencephalopathy
• Dystonia with basal ganglia calcification
• Progressive dystonia with normal brain MRI or
generalised atrophy

63. Specific investigations
Etiology Test
Suggested family history/early onset Genetic testing
Neiman Pick type C Lysosomal enzyme assay, skin
biopsy,genetic testing
Aminoacidemias Urinary TMS
Adrenoleukodystrphy VLCFA level
Mitochondrial Muscle biopsy, genetic panel
Dopamine synthesis pathway defect CSF analysis
GLUT1 deficiency CSF:Serum glucose <0.4
YOPD DAT-SPECT scan