Movement Disorders
Movement Disorders
* Background
o AKA Extrapyramidal Disorders
o These disorders impair the regulation of voluntary motor activity w/o affecting the strength, sensation, or cerebellar fcn.
o Result from dysfunction of the basal ganglia
+ Caudate
+ Putamen
+ Globus Pallidus
+ Subthalamic Nucleus
+ Substantia Nigra
+ Lentiform Nucleus
# Putamen & Globus Pallidus
+ Corpus Striatum
# Lentiform Nucleus + Caudate Nucleus
* Basal Ganglia Circuitry (Fig 7-1)
o Corticocortical Loop:
Cerebral Cortex
Caudate & Putamen
Internal Segment
Globus Pallidus
Thalamus
* Basal Ganglia Circuitry (Fig 7-1)
o Nigrostriatal Loop:
Substantia Nigra
Caudate & Putamen
* Basal Ganglia Circuitry (Fig 7-1)
o Striatalpallidal Loop:
Caudate & Putamen
External Segment
Globus Pallidus
Subthalamic Nuclei
Internal Segment
Globus Pallidus
* Types of Abnormal Movements
o Tremor: rhythmic movement characterized by when it occurs
+ Postural Tremor
# During sustained posture
+ Intention Tremor
# During movement; absent at rest
+ Resting Tremor
# At rest
o Chorea: irregular muscle jerks
+ Florid Cases
# Fully developed
# Forceful movements of limbs, head, facial grimacing, & tongue movements
+ Mild Cases
# Characterized by:
* Clumsiness
* Milkmaid grasp
* Absent in sleep
o Hemiballismus
+ Unilateral Chorea
+ Involves the proximal muscles
+ Vascular disease of contralateral subthalamic nucleus
o Athetosis
+ Continued slow, sinuous, & writhing movements
o Dystonia: sustained athetotic movements
+ Segmental Dystonia
# Affects one or more limbs
+ Focal Dystonia
# Affects localized muscle groups
+ Palliative/Provocative
+ Causes
o Myoclonus
+ Definition
+ Classification
+ Generalized: widespread
# Physiological
# Essential
# Epileptic
# Symptomatic
+ Segmental: more localized
o Tics
+ Definition
+ Palliative/Provocative
+ Types
# Transient Simple: common in children, resolve w/I 1 yr
# Chronic: any age, no tx
# Persistent Simple or Multiple: onset before 15 yoa, resolve in adults
# Chronic Multiple: Tourette’s Sydrome
* Hypokinetic Movement Disorders
o Parkinson’s Disease
* Hyperkinetic Movement Disorders
o Huntington’s Disease
o Wilson’s Disease
o Tourette’s Syndrome
o Restless Leg Syndrome
* Parkinson’s Disease - Hypokinetic
o Defined as a syndrome consisting of variable combination of tremor, rigidity, bradykinesia, and characteristic disturbance of gait and posture
o Onset: mid-late life; mean age is 57 yrs
o Epidemiology:
+ Affects all ethnicities
+ has equal M/F distribution
+ occurs 1-2 per 1,000 people in general population
+ occurs 1 per 100 people that are over 65 yrs
+ 4th most common disease in the elderly
* Parkinson’s Disease - Hypokinetic
o Cause: unknown
o Pathophysiology:
+ Loss of dopaminergic cells in the substantia nigra
# Dopamine’s normal function
+ Over excitation of the caudate & putamen
+ Over excitation of the corticospinal tracts
+ Oscilation of feedback
+ Decrease in thalamic excitation of the motor cortex
o Four Hallmark Signs
+ Resting Tremor (Pill-Rolling)
+ Rigidity (Lead-Pipe or Cogwheel)
+ Bradykinesia
+ Flexed Posture with shuffling gait (Festinating)
o Examination:
+ History
+ Phsyical Findings:
# Passive movement
# Muscle Strength
# Sensory
# Deep Tendon Reflexes
# Autonomic
# Myerson’s Sign
# Pull Test
o Diagnosis:
+ Four Hallmark signs
+ Tremor is absent in 30% of patients
o Differential Diagnosis
+ Involuntary tremor vs. Intentional tremor
+ Depression
+ Wilson’s Disease
+ Huntington’s Disease
o A neurodegenerative disorder which predominately has behavioral, cognitive, or signs
o Onset: Usually begins during adult life
o Epidemiology:
+ 5-10 per 100,000 in the US
+ 50% chance to pass on the disorder
+ Anticipation
+ Paternal Descent
* Huntington’s Disease – Hyperkinetic
o Cause: Autosomal Dominant Disorder
o Pathophysiology:
+ Mutation on chromosome 4: CAG repeats
+ CAG Normal Function: codes for glutamine
+ Over-expression of the gene: i.e. excess glutamine
+ Uncertainty?
* Huntington’s Disease – Hyperkinetic
o Cause: Autosomal Dominant Disorder
o Pathophysiology:
+ Pathological Changes
# Atrophy & neuronal degeneration of cortex
# Hallmark: caudate atrophy
+ Projected Conclusion?
# Over activity
# Under activity
o Examination:
+ Physical Findings
# Initial Findings
* Gradual onset
* Slowed saccadic movements 1st sign
* In 85% chorea is predominate movement disorder
# Juvenile Form
* AKA The Westphal Variant
* Rigidity & bradykinesia
* Tremors, Dystonic postures, & Ataxia
* Mental retardation, Seizures, & myoclonus
o Examination:
+ Physical Findings
# Adult Onset
* Prominent chorea
* Bradykinesia
* Postural reflex compromise
# Terminal Phase
* Dysarthria, dysphagia, & respiratory difficulties
# General
* Cognitive impairment
* Depression
* Psychiatric disorders
* Wilson’s Disease – Hyperkinetic
o Onset
+ Hepatic Dysfunction – 11 yoa
+ Neurological Dysfunction – 19 yoa
o Epidemiology
+ Rare
+ 1 in 40,000 people
o Cause: Autosomal Recessive Disorder
o Pathophysiology
+ Abnormal copper metabolism
+ Deposition of copper in tissues
o Examination
+ Physical Findings
# Children: hepatic dysfunction predominates
* Sardonic Smile
* Behavioral problems
# Adults: neurological dysfunction predominates
* Parkinsonian features
# General
* Hallmark: Kayser-Fleischer Rings
* 1/3 experience psychiatric symptoms
* Other ocular abnormalities
* Gilles de la Tourette Syndrome – Hyperkinetic
o Diagnosed when childhood onset tics are multifocal, motor or vocal, lasting longer than 1 yr and naturally wax and wane
o Cause: unknown
o Onset: 2-21 yoa
o Male predilection
* Gilles de la Tourette Syndrome – Hyperkinetic
o Examination
+ Physical Findings
# Simple Tics
* Motor: blinking, facial grimacing, shoulder shrugging
* Vocal: throat clearing, grunting, snorting, barking
# Complex Tics
* Motor: hopping, skipping, Echopraxia
* Vocal: Coprolalia, Echolalia, Palilalia
* Restless Legs Syndrome – Hyperkinetic
o Common movement disorder
o Diagnostic Criteria
# Desire to move limbs which is associated with unpleasant sensations
# Restlessness
# Worsening of symptoms @ rest w/ temporary relief w/ movement
# Worsening of symptoms @ night
* Restless Legs Syndrome – Hyperkinetic
o Common Descriptions
+ Always unpleasant, but not necessarily painful
+ Need to move
+ Crawling
+ Tingling
+ Itching
+ Restless
Movement Disorders.ppt
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