Movement disorders overview

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Questions and Answers

What role does the basal ganglia play in movement control?

Regulates sensory feedback for movement

Facilitates wanted movement and suppresses unwanted movement (correct)

Only suppresses wanted movements

Only facilitates unwanted movements

Which of the following is NOT a symptom of movement disorders associated with cerebellar disease?

Severe muscle rigidity (correct)

Impaired coordination

Dysdiadochokinesia

Hyperkinesias

What is the function of the cerebellum in movement?

Exclude sensory input from motor control

Initiate all voluntary movements

Facilitate reflexive movements only

Provide anticipatory and corrective feedback during movement (correct)

Which of the following accurately describes the thalamus in the context of movement?

It integrates and connects various information crucial for movement control Signup and view all the answers

What is a possible cause of dysfunction leading to movement disorders?

Genetic mutations or environmental factors Signup and view all the answers

What is a common environmental risk factor for the condition characterized by the loss of dopaminergic neurons in the substantia nigra?

Exposure to industrial chemicals Signup and view all the answers

Which symptom is typically associated with the early stages of Parkinson's disease?

Subtle decrease in dexterity Signup and view all the answers

What is a characteristic symptom of Huntington's disease?

Chorea Signup and view all the answers

Which demographic is most likely to develop Parkinson's disease?

Males over 60 Signup and view all the answers

What is one of the '5 D's' associated with VBAI?

Dizziness Signup and view all the answers

Which of the following symptoms signifies cerebellar dysfunction in PICA occlusion?

Ipsilateral facial pain Signup and view all the answers

In Dandy-Walker Syndrome, what is a common sign of increased intracranial pressure?

Irritability Signup and view all the answers

Which type of tremor is described as 'occurring at rest'?

Parkinsonian tremor Signup and view all the answers

What best describes an essential tremor?

Affects postural and kinetic movements Signup and view all the answers

What is a potential outcome of untreated Huntington's disease?

Death 15-20 years after onset due to complications Signup and view all the answers

What differentiates essential tremor from other types of tremors?

It can be emotionally triggered Signup and view all the answers

Which demographic shows a higher prevalence of Parkinson's disease?

Males over 60 Signup and view all the answers

What is typically not a direct symptom of VBAI?

Hypertension Signup and view all the answers

Study Notes

Cerebellar Disease

Symptoms: Impaired coordination, bradykinesia, involuntary movements (hyperkinesias), tremor, chorea/dystonia, nystagmus, impaired gait.
Extrapyramidal Tracts: Pathways involved in reflexes (e.g., head/trunk movement in response to noise), locomotion, complex movements, and postural control. Modulated by the cerebellum, basal ganglia, vestibular nuclei, and parts of the cerebral cortex.
Mechanics: The premotor cortex initiates movement. Corticospinal and corticobulbar tracts control gross voluntary muscle movement. Basal ganglia facilitate wanted motions and suppress unwanted ones. The cerebellum uses feedforward (anticipatory) and feedback (corrective) mechanisms during movement. Sensory system (proprioception) and thalamus relay information.
Causes: Vascular (posterior circulation issues), infectious (abscesses, viral cerebellitis, Creutzfeldt-Jakob disease), neurological (demyelination), neoplastic (tumors), degenerative (spinocerebellar ataxias, multi-system atrophy), intoxication (alcohol, phenytoin), metabolic (myxoedema, hypoglycaemia, hypoxia, vitamin B1 deficiency).
Symptoms (Cerebellar Dysfunction): Ataxia, decomposition of complex movements, impaired balance (possible acute loss of extensor muscle control).
Signs (Cerebellar Dysfunction): Pendular reflexes (hypotonia), dysdiadochokinesia (impaired rapid alternating movements), action/intention tremor, rebound phenomenon, nystagmus.

Parkinson's Disease

Aetiology: Unknown. Possible factors include gene mutations, environmental factors (smoking, herbicides), and meperidine analogue toxicity.
Pathology: Loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). Remaining cells contain Lewy bodies. The disease progresses to affect other brain regions.
Prevalence: Approximately 190 per 100,000 (1% of people >60).
Sex Ratio: 3:2 (male to female).
Onset Age: Typically >50 years old.
Familial cases: 5% of Parkinson's cases are familial.
Risk Factors: Genetics, environmental factors (rural living, chemical exposures, infections), age (higher risk with increasing age), male sex more common than female sex.
Symptoms (Early): Subtle dexterity decline, tremor (pill-rolling), reduced arm swing on affected side, soft voice, reduced facial expression (hypomimia), reduced sense of smell, sleep disturbances, autonomic issues (sweating, constipation), generalized lassitude, weakness, and malaise.
Symptoms (Later): Rigidity (cogwheel, lead pipe), bradykinesia (difficulty initiating movement affecting facial expression, speech, swallowing, and gait), shuffling gait, flexed posture, possible depression, dementia.

Huntington's Disease

Description: Rare autosomal dominant disorder with progressive neuronal loss in the striatum, frontal, and parietal cortex. Associated with GABA, acetylcholine, and dopamine pathways.
Onset: Adulthood (30-50 years old).
Symptoms: Chorea (irregular, jerky involuntary movements) which may be accompanied by or replaced by dystonia and parkinsonism symptoms. Early irritability, loss of interest, cognitive decline, memory issues, speech problems, behavioral disturbances (affective illness, depression, bipolar).
Prognosis: Death typically 15-20 years after onset due to complications such as aspiration pneumonia or suicide.

Vertebrobasilar Arterial Insufficiency (VBAI)

Causes: Atheroma (plaque buildup) or dissection (tearing) of the artery.
Symptoms (5 D's, 3 N's): Dizziness, dysphagia (difficulty swallowing), dysarthria (speech difficulty), diplopia (double vision), drop attacks; nausea, numbness, nystagmus; ataxia.

Posterior Inferior Cerebellar Artery (PICA) Occlusion

Description: Common type of brainstem stroke, also called lateral medullary infarct or Wallenberg's syndrome.
Symptoms: Cerebellar signs (vertigo, ipsilateral hemiataxia, dysarthria), ipsilateral facial pain (CN5), contralateral loss of pain and temperature sensation in the extremities (crossed syndrome), ptosis (drooping eyelid), meiosis (constricted pupil), interruption of descending sympathetic fibers.

Dandy-Walker Syndrome

Description: Rare congenital malformation causing dilation of ventricles (especially the fourth ventricle), underdeveloped or separated cerebellar hemispheres, and enlarged posterior fossa.
Symptoms: Delayed motor development, progressive enlargement of the skull (or back of head), increased intracranial pressure (ICP) symptoms (irritability, vomiting), signs of cerebellar dysfunction, cranial nerve dysfunction.
Treatment: Shunt for hydrocephalus, treatment of associated symptoms.

Tremor

Description: Rhythmic, regular oscillation of a body part. Common locations include hands, jaw, tongue, and head.
Types: Resting, postural, intention, end-point.
Essential Tremor: Most common. Familial link, slowly progressive postural or kinetic tremor of both upper limbs. Can also affect the head, voice, jaw, lips, and face. Starts in one extremity, progresses to both. Can be intermittent or emotionally triggered, variable amplitude. Improves with relaxation and sleep. Little impact on activities of daily living (ADLs).
Abnormal Tremor: Parkinsonian tremor (rest tremor, "pill-rolling" motions), cerebellar tremor (intention tremor), postural tremor, end-point tremor, drug-induced/metabolic tremor (e.g., adrenaline, alcohol withdrawal, hyperthyroidism), psychogenic tremor.

Arnold-Chiari Malformation

Chiari II: Cerebellum and brainstem impacted, always with myelomeningocele (spina bifida). Common symptoms include hydrocephalus at birth and syringomyelia. May present with occipital pain, weakness.
Types III/IV: Rare, profound neurological deficits.
Treatment: Hydrocephalus shunt, decompression surgery (if asymptomatic, surgery not needed).

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Description

This quiz covers the symptoms, mechanics, and causes of cerebellar diseases. It explores the role of extrapyramidal tracts and how they are modulated by different brain structures. Test your knowledge on the complexities of movement coordination and the impact of various neurological conditions.