Ataxia
Incoordination of voluntary movement due to cerebellar, sensory, or vestibular dysfunction.
Causes of Ataxia
Cerebellar disease (stroke, tumour, alcohol, paraneoplastic).
Peripheral neuropathy (sensory ataxia).
Vitamin B12 deficiency.
Drugs (phenytoin, benzodiazepines)
Features of Ataxia
Gait unsteadiness, wide-based stance, intention tremor, dysdiadochokinesis, slurred speech.
Dystonia
Sustained or intermittent muscle contractions causing abnormal postures or twisting movements.
Causes of Dystonia
Idiopathic, Parkinson’s disease, drug-induced (dopamine antagonists).
Examples:
Cervical dystonia (torticollis), blepharospasm.
Chorea
Brief, irregular, non-repetitive involuntary movements (“dance-like”).
Tx for Dystonia
Botulinum toxin, physiotherapy, stop causative drugs.
Causes of Chorea
Huntington’s disease, drug-induced (levodopa, antipsychotics), stroke, metabolic (thyrotoxicosis).
Management of Chorea
Treat underlying cause, dopamine-blocking agents (e.g. tetrabenazine) for symptom relief.
Myoclonus
Sudden, brief, shock-like jerks due to muscle contractions.
Causes of Myoclonus
Metabolic (uraemia, hepatic failure), anoxia, Creutzfeldt–Jakob disease, medications (opioids, antidepressants).
Management of Myoclonus
Treat cause; may use clonazepam or valproate for symptomatic control.
Tremor
Rhythmic oscillatory movement due to alternating muscle contractions.
Types of Tremor and their causes
Resting tremor: Parkinson’s disease.
Action (postural/kinetic) tremor: Essential tremor, hyperthyroidism, drug-induced (β-agonists).
Intention tremor: Cerebellar disease.
Managment of Tremor
Essential tremor → propranolol or primidone.
Parkinsonian tremor → dopaminergic therapy.
