Week 3 - Movement Disorders Flashcards
What is the role of the basal ganglia in movement?
Decision to move Direction of movement Amplitude of movement Speed of movement Records pre-learned motor sequences Generates feedback loop to guide future movement patterns
What is the basal ganglia?
An area in the brain that controls movement.
What are the 4 parts of the basal ganglia?
Corpus striatum
Globus Pallidus
Substantia nigra
Subthalamic nucleus
What makes up the Corpus Striatum?
The caudate nucleus and putamen
What makes up the Globus Pallidus?
Internus and externus
What is the thalamus?
The gatekeeper to the cortex
Under tonic inhibition regulated by the basal ganglia
Once this inhibition is removed, signals can be sent by the basal ganglia, which is how the basal ganglia controls movement
Which is the input nuclei of the basal ganglia?
The Corpus Striatum
Which is the output nuclei of the basal ganglia?
The Globus Pallidus
What is the role of the substantia nigra?
Processes information received by the corpus striatum.
Further inhibits the Globus Pallidus
What is the role of the subthalamic nucleus?
Processing information received by the corpus striatum
Excites the globus pallidus
What causes movement disorder?
Errors in basal ganglia mechanism
What pathways does the basal ganglia modulate movement?
Direct and indirect pathways
What is a direct pathway?
The direct pathway, sometimes known as the direct pathway of movement, is a neural pathway within the central nervous system through the basal ganglia which facilitates the initiation and execution of voluntary movement.
What is an indirect pathway?
The indirect pathway, sometimes known as the indirect pathway of movement, is a neuronal circuit through the basal ganglia and several associated nuclei within the central nervous system which helps to prevent unwanted muscle contractions from competing with voluntary movements.
What are the 2 types of classification of movement disorder?
Hyperkinetic and Hypokinetic
What are the 2 types of Hypokinetic disorders?
Bradykinesia and rigidity
What are the 5 types of Hyperkinetic disorders?
Tremor Chorea Dystonia Myoclonus Tics
What is bradykinesia?
Bradykinesia means slowness of movement, a reduction in movement in both amplitude and speed
What conditions are hypotonic movement disorders seen in?
Parkinsons Multiple System Atrophy Progressive Supranuclear Palsy Lewy body dementia Stroke Medications
What is Ataxia?
Voluntary muscular incoordination that present as jerky, intermittent movement
What are the 3 types of ataxia?
Cerebellar
Sensory
Vestibular
What is Parkinson’s Disease?
A chronic neurodegenerative disorder characterised by resting tremor, bradykinesia, rigidity and postural instability
What is Parkinsonism?
Parkinsonism is a general term that refers to
a group of neurological disorders that cause
movement problems similar to those seen
in Parkinson’s disease such as tremors, slow
movement and stiffness
What is the most common cause of parkinsonism?
Parkinson’s disease
What is the average age of onset for Parkinson’s?
60 years
What causes Parkinson’s disease?
Loss of dopaminergic neurons especially in the substantia nigra
What percentage of dopaminergic neurons are lost before Parkinson’s systems appear?
80%
What are the risk factors of Parkinson’s disease?
Idiopathic (no known cause)
Genetic factors (Age 60+, gender male)
Environmental factors
What are the motor symptoms of Parkinson’s
Bradykinesia Rigidity Postural instability Dysphonia/Dysarthria Dysphagia
What are non-motor causes of Parkinson’s Disease?
Cognitive impairment Mood disorders insomnia anosmia drooling constipation
What is an example where bradykinesia is seen?
Alternative, repetitive movements such as tapping or handwriting (start normal and then diminish in size)
What are the 3 main signs of bradykinesia in parkinson’s?
Falls, freezing and festinations
What is festination?
Small shuffling gate
What is lead pipe rigidity?
Smooth consistent rigidity in movement. Involuntary stiffening (rigidity) of muscles that remains the same even while being passively manipulated
What is cogwheeling?
A jerky, ratchet like quality of movement caused by rigidity superimposed on a tremor.
Muscular stiffness is throughout the range of passive movement in both extension and flexion.
What tremor is most commonly observed in parkinson’s disease?
pill-rolling tremor
How are Parkinson’s patients classified?
The Hoehn and Yahr Scale
Unified PD rating scale
What are the features of the Hoehn and Yahr scale?
Published in 1967
5 stages
Has been extensively modified
What are the features of the Unified PD rating scale
Comprehensive
4 parts
Intellectual function, ADLs, Motor Exam, motor complications
Time consuming
How is Parkinson’s medically managed?
Dopamine replacement therapy
Dopamine Agonist
Anticholinergics
How is Parkinson’s surgically managed?
Deep brain Stimulation
What is Muscular System Atrophy?
Affects autonomic functions
A rare, degenerative neurological disorder affecting your body’s involuntary (autonomic) functions, including blood pressure, breathing, bladder function and motor control.
What causes MSA?
Idiopathic
Overproduction and accumulation of alpha-synuclein in the brain
What Does MSA affect?
Basal ganglia
Cerebellum
Brain stem
What is the age of onset for MSA?
54-60 years
Which develops faster, PD or MSA?
MSA
What are clinical features of MSA?
Akinetic rigid parkinsonism Autonomic failure Cerebellar ataxia Urogenital dysfunction Action tremor PISA syndrome Lateral flexion of the spine Severe anterior flexion of the spine Jerky myoclonic posture
What is Progressive Supranuclear Palsy?
Causes balance, movement, vision, speech, swallowing problems
A rare neurological condition that can cause problems with balance, movement, vision, speech and swallowing.
What causes PSP?
It is idiopathic, associated with accumulation of protein tau
What are the clinical features of PSP?
Atrophy of subthalamic nucleus, brainstem and superior cerebellar peduncle
What are symptoms of PSP?
Axial rigidity in extension restricted eye movements falls when walking downstairs Diplopia Light sensitivity Blepharospasm Memory/behaviour changes Dysarthria Dysphagia
What is Chorea?
Involuntary non-rhythmic, abrupt dance like movements
What is tremor?
Involuntary, rhythmic, alternating movements involving one or more joints
What are the 3 types of tremor?
Essential, resting and intentional
What is dystonia?
Involuntry, slow, sustained contractions of agonist +/- antagonist muscles
What is myoclonus?
Involuntary sudden, brief muscle contractions or inhibitions (shock like)
What are tics?
Involuntary, repetitive, stereotyped movement and vocalisations
What is athetosis?
Involuntary, slow, writhing movements
What are agonist muscles?
The muscle that is contracting
What are antagonist muscles?
The muscles that are relaxing or lengthening
What is huntington’s disease?
An inherited progressive neurodegenerative disease.
True or false: Huntington’s disease affects males and females equally
True
What characterises Huntington’s disease?
Choreiform movements
Psychiatric problems
Dementia
What function does Huntington’s affect?
Motor
Cognitive
Emotional function
What are choreiform movements?
Random, brief, and non-rhythmic movements
`What is the age of onset for Huntington’s disease?
30-40 years
How is Huntington’s Disease diagnosed?
Diagnosis is based on clinical features
Positive family history
Confirmed with genetic testing
Axial MRI to identify caudate atrophy
What is the prognosis of Huntington’s disease?
15-25 years
What are the signs of Huntington’s disease?
Chorea Hypotonia with hyperreflexia Progressive loss of motor control Abnormal eye movements Psych symptoms Cognitive impairment and dementia
What is hyperreflexia?
Hyperreflexia is defined as overactive or overresponsive reflexes
How is Huntington’s disease managed?
Symptomatic management and therapy
What symptomatic management is suitable for Huntington’s disease?
Medication to supress movements
Antipsychotics
Antidepressants
What therapy can assist with Huntington’s disease?
Lifestyle management
Allied health management for feeding, communication, mobility
Palliative care
What is Tourette’s Syndrome?
A common neurophysiological disorder
How is Tourette’s characterised?
By repetitive stereotyped involuntary movement and vocalisations called tics
What causes tics?
Dopaminergic imbalances
What other conditions are associated with Tourette’s?
ADHD and OCD
What are examples of movement tics?
Shrugging eye blinking head jerking nose twitching swallowing coughing lip twitching
What are examples of vocal tics?
Grunting
Barking
Throat clearing
Repetitive words
What is the cause of Tourette’s?
Idiopathic
What is the average age for onset of Tourette’s?
7-10 years old
True or false: Tourette’s affects more females than males?
False, affects males 3-4 times more than females
How is Tourette’s managed?
Medication for suppression of tics
