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Flashcards in Dystonia Deck (32):

What is the most common movement disorder

essential tremor


What is the second most common movement distorder



What is the 3rd most common movement disorder



Dystonia: definition

sustained muscle contractions causing repetitive twisting movements or abnormal postures during functional movements
*misrepresentation of the body in the brain


3 axes of classification

1. etiology/cause (primary, heterotodegenerative, secondary)
2. Age of onset (early, late)
3. Distribution (focal, segmental, multifocal, generalized, hemi-dystonia)


3 types of primary dystonias

1. Primary "pure"
2. Primary plus
3. Primary Paroxysmal


Primary Pure dystonia

Torsion dystonia is the only clinical sign
No identifiable exogenous cause or other inherited or degenerative disease


Primary plus dystonia

Torsion dystonia is a prominent sign, but is associated with another movement disorder (myoclonus, parkinsonism)
No evidence of neurodegeneration


Primary Paroxysmal Dystonia

torsion dystonia occurs in brief episodes with normalcy in between


3 forms of primary paroxysmal dystonia

1. Paroxysmal kinesigenic dyskinesia (PKD)- attacks induced by sudden movement
2. paroxysmal exercise-induced dystonia (PED)- attacks induced by exercise
3. Non-kinesigenic form (PNKD)- attacks induced by alcohol, coffee, tea, etc


Heredodegenerative Dystonias

dystonia is a feature (amongst other neurodegenerative signs)
example = wilson's disease
Both hereditary and degenerative


Secondary Dystonias

Dystonia is a symptom of identified neurological condition (brain tumor, focal brain lesion, exposure to drugs and chemicals)


Early-Onset dystonia

onset at 20-30yrs (before 30)
starts in single leg or arm, progresses to involve other limbs and the trunk


Late onset dystonia

starts in the neck, cranial muscles, or one arm
remains localized with restricted progression to adjacent muscles


Focal dystonia

single body segment (writers cramp)


Segmental dystonia

Contiguous body regions (cranial and cervical, cervical and upper limb- Cervical dystonia is common)


Multifocal dystonia

non-contiguous body regions (upper limb and lower limb, cranial and upper limb)


Generalized dystonia

both legs and at least one other body region (usually one or both arms)



half of the body (usually secondary to a structural lesion in the CL basal ganglia)
Cerebellum --> control of IL side affected
Basal Ganglia --> Control of CL side affected


Risk factors of dystonia

1. repetition/excessive practice
2. Poor ergonomics
3. stress
4. trauma/anatomic defects
5. compulsive personality, perfectionists, impatient
6. environment
7. aberrant physiology
8. genetics (susceptibility gene)


physiological circuits involved in dystonia

1. Basal ganglia
2. cerebellar
3. SMA (primary motor cortex)
4. Sensory motor cortex


Pathogenesis of excessive practice and dystonia

excessive practice --> degradation of cortical and subcortical representation --> loss of sensitivity in distinguishing between sensory stimuli
*loss of sensitivity: excessive/persistent firing of neurons in both sensory and motor cortex independent of the stimuli


Can excessive practice lead to dystonia on its own?

No! must be in combination with genetic mutations, environmental causes, and susceptibility genes



ability to identify objects drawn on your hand with another finger without visual cues



being able to identify objects by using only tactile perceptors and fingers (no visual cues)


Components of the neuro exam for dystonia

1. motor exam
2. sensory exam (graphesthesia, stereognosis)
3. evaluation of task performance


Fahn-Marsden Movement Scale

one of the most common scales used to evaluate presence of dystonia
looks at provoking and severity factors to grade dystonia


Fahn-Marsden Movement Scale: Provoking Factors

0 = none
1 = only with particular action (writer's dystonia)
2 = with many actions
3 = on action of distant part of body or intermittently at rest
4 = at rest


Fahn-Marsden Movement Scale: Severity Factor

0 = none present
1 = slight dystonia, clinical insignificance
2 = mild, obvious dystonia, but not disabling
3 = moderate, able to grasp with some manual function
4 = most severe, no functional grasp


Factors of successful intervention in dystonia

1. time commitment (~30-60mins, must stop the abnormal movement)
2. Expectation: the pt must expect to get better and recognize it may take up to a year
3. supervision: for watching ergonomics and techniques


Practice principles of dystonia

1. activities must be learned based, requiring focused attention
2. Address reacquisition of normal movement, then maitenance of the normal movement (break the task into subtasks)
3. Begin practice with a similar task, but only include the normal movements
4. May begin with mental rehearsal (firing 30% of the neurons)
5. start practice in an unusual nontarget position (but ultimately in the normal position)
6. consider compensatory strategy
7. short practice intervals, spaced over time
8. globally repetitive, but progressed with small increments
9. include sensory modificiation strategies
10. mirror imagery


Sensory Modification Techniques

1. enhancement of sensory inputs- splint/tape, modifying interface
2. reinforce task performance with other senses (watching video tape, listening to the instrument)