Limb Weakness Flashcards
What are causes of sudden onset limb weakness?
Second to minutes
Trauma e.g. displaced fractures
Vascular insults e.g stroke, TIA
Spinal disc prolapse
What are causes of subacute limb weakness?
Hours to days
Progressive demyelination e.g. Guillain-Barré syndrome, MS
Slowly expanding haematoma e.g. subdural
What are causes of chronic onset limb weakness?
Weeks to months
Slow growing tumour
Motor Neurone Disease
Where are the possible anatomical locations for a lesion causing limb weakness?
Pathway for coordination of limb movement
- Cerebral cortex
- Corona radiata
- Pons
- Corticospinal tract
- Peripheral nerve
What questions do you want to ask a patient with limb weakness?
Exact time of onset Visual and speech disturbances Headache Seizure Loss of consciousness Neck or back pain Trauma to the head RFs for stroke
Why do you ask about the exact time of onset?
Thrombolysis window is 4.5 hours from onset
Why do you ask about visual and speech disturbances?
Tells you the problem is in the brain not PNS
Why do you ask about headache?
Unusual in stoke so more likely SA haemorrhage
or
Unilateral headache preceding limb weakness indicates hemiplegic migraine
or
Gradual-onset headache indicates intracranial mass e.g. slowly expanding subdural haemorrhage
Why do you ask about loss of consciousness?
Not typical of stroke - more likely hypoglycaemia
Why do you ask about neck/back pain?
Suggests spinal pathology
Guillan-barré is accompanied by back pain
What are upper motor neurone (CNS, spinal cord) lesion signs?
Increased - Tone - Reflexes - Plantars Clonus
What are lower motor neurone (peripheral) signs?
Decreased - Tone - Reflexes Fasciculation Wasting
What is suggestive of a lesion in Wernicke’s area?
Temporal lobe
Receptive dysphasia
Speaks fluently but jumbling
Cannot comprehend language
What is suggestive of a lesion in Broca’s area?
Frontal lobe
Expressive dysphasia
Comprehension normal
Cannot find words or speak fluently
Where would a lesion be in someone experiencing hemispatial neglect?
Parietal lobe
