Limb weakness (oxford clin cases) Flashcards
What pathology does acute (sudden onset) limb weakness indicate?
Trauma or vascular problems (eg stroke/TIA)
What pathology does subacute (hours to days) limb weakness indicate?
Multiple sclerosis
Guillian barre syndrome
Slowing expanding haematoma
What pathology does chronic (weeks to months) limb weakness indicate?
Slow growing tumour
Progressive degeneration eg motor neurone disease
What are common causes of sudden onset limb weakness that originate in the brain?
Ischaemic stroke
TIA
Haemorrhagic stroke
Hypoglycaemia
What are common causes of sudden onset limb weakness that originate in the spinal chord?
Spinal disc prolapse
Spinal cord infarction
What are common causes of sudden onset limb weakness that originate in the peripheral nerve?
Peripheral nerve ischaemia
What are common causes of subactute onset limb weakness that originate in the brain?
Multiple sclerosis
Haematoma
Tumor
What are common causes of subactute onset limb weakness that originate in the spinal chord?
Multiple sclerosis
Tumor
What are common causes of gradual onset limb weakness that originate in the muscle?
Myasthenia gravis
If someone has limb weakness, what other symptoms will make you think its a problem in the brain rather than in the spine or peripheral nervous system?
Deficits in speech or vision
If someone has speech deficit/visual problems alongside limb weakness where is the problem most likely to be?
Brain
What type of headache will a stroke/TIA present with?
It is unlikely there will be headache
What does a unilateral headache preceding the limb weakness indicate?
Hemiplegic migraine
What does a gradual onset headache preceding limb weakness indicate?
Intercranial mass (slowing expanding haemorrhage?)
What symptoms are not typical of stroke and would make you think something else is going on?
Seizure
Loss of conciousness
Headache
What are the 3 main risk factors for stroke?
Previous stroke or TIA
Atrial fibrillation
Atherosclerotic risk factos (hyperlipidaemia, smoking, diabetes mellitus, hypertension, smoking, family hx)
If a patient is ignoring half of their sensory world where should you suspect there may be a lesion?
Parietal lobe
If there is complete blindness in one eye where does this suggest there may be a lesion?
Optic nerve
If there is homonymous hemianopia where might there be a lesion?
Between the optic chiasm and visual cortex
What is homonymous hemianopia?
Loss of visual field in the same regions in both eyes
Where is there likely to be a lesion if the eye deviated away from the lesion?
Cortex
Where is there likely to be a lesion if the eye deviated towards the lesion?
Brain stem
Where will an infarction in the spinal column spare the dorsal column?
An anterior infarction
What lesion does parasthesia or loss of sensory modality in the limb indicate?
Peripheral lesion or nerve root lesion
What sensory modalities is the spinothalamic tract responsible for?
Pain and temperature
What sensory modalities is the dorsal column responsible for?
Light touch
Vibration
Proprioception
What region of the motor cortex is associated with the lower limb?
The most medial part
What region of the motor cortex is associated with the upper limb?
More medial aspects
What is the blood supply to the medial aspect of the motor cortex?
Anterior cerebral artery
What is the blood supply to the lateral aspects of the motor cortex?
Middle cerebral artery
After someone has a stroke, what are some complications they are at risk of and why?
Pressure ulcers- if they are not mobilised quickly and are lying in bed in one position
Aspiration pneumonia- patients often struggle to swallow and can therefore aspirate food which can give them pneumonia
What different aspects are considered when analysing disability in someone after they have had a stroke?
Swallowing Visual fields Gait Speech and language Use GCS
What drugs are patients commonly put on for long term management after they have a stroke?
Statin
ACE inhibitor/ something to reduce their blood pressure
Clopidrogrel/ some type of blood thinner
How does treatment for a haemorrhagic stroke differ from treatment for an ischaemic stroke?
If a stroke is haemorrhagic, aspirin should not be given immediately as the blood does not need to be thinned. Furthermore when prescribing prohyliactiv medication, blood thinners like clopidrogrel do not need to be given
What is the treatment for haemorrhagic stroke?
ABCD, then check and stabilise INR
What second line investigations are done in a specialist stroke unit?
VTE/PE prophylaxis
Bedsore/ulcer prevention
Nutritional assesment (inc swallow)
What are the 2 main treatments for an ischaemic stroke? How is it decided which should be used?
Aspirin or thrombolysis
Thrombolysis can only be performed if the patient arrives with 4.5 hours of onset of the stroke, a specialist will review the patient and decide if its beneficial to thrombolyse them to break up the clot that is causing the stroke
What are risks of thrombolysis as a treatment for ischaemic stroke?
Haemorrhage
What is immediately done when someone comes in with a suspected stroke and why?
Non contrast CT head
This is to rule out haemorrhagic stroke
What is the first line investigation to look for carotid artery stenosis?
Doppler ultrasound
What is the difference between anticoagulants and anitplatelets
Anticoagulants= affect the clotting cascade Antiplatelets= affect platelet aggregation
When are anticoagulants used and when are antiplatelets used?
Antiplatelets are used when clots form for reasons besides atrial fibrillation because they prevent platelet aggregation and atrial fib occurs due to issues with the clotting cascade
Anticoagulants are used for prevention of DVT, PE etc/ things that occur due to atrial fibrillation
