Limb weakness Flashcards
What things may be confused for limb weakness?
- Ataxia
- Reduced sensation
- Lumb too painful to move
What may cause a sudden onset (secs to mins) of limb weakness?
- trauma e.g. displaced vertebral fractures due to major trauma
- vascular insult e.g. stroke, TIA
What may cause a subacute onset of limb weakness (hours to days) of limb weakness?
- progressive demyelination (e.g. Guillain-Barre syndrome, MS)
- slowly expanding haematoma (e.g. subdural haematoma)
What may cause a chronic onset (weeks to months) of limb weakness?
- Slow growing tumour
2. Motor neuron disease
What is the pathway that could be damaged in limb weakness?
- cerebral cortex
- corona radiata
- internal capsule
- pons
- along corticospinal tract of spinal cord
- out along a nerve root
- down a peripheral nerve to neuromusclar junction
- muscle itself
What are the differential diagnosis for a brain lesion with a sudden onset of limb weakness?
- Ischaemic stroke
- TIA
- Haemorrhagic stroke
- Hemiplegic migraine
- Todd’s palsy (post-seizure paralysis)
- Hypoglycaemia
What are the differential diagnosis for a spinal cord lesion with a sudden onset of limb weakness?
- Spinal disc prolapse
- Spinal cord transection
- Spinal cord infarction
What are the differential diagnosis for a nerve lesion with a sudden onset of limb weakness?
- spinal disc prolapse
2. vertebral fracture
What are the differential diagnosis for a peripheral nerve or nerve plexus lesion with a sudden onset of limb weakness?
- Acute limb ischaemia (e.g. peripheral artery embolus)
2. Traumatic nerve injury (e.g. laceration
What are the differential diagnosis for a brain lesion with a subacute onset of limb weakness?
- MS
- Haematoma (e.g. subdural, extradural)
- Tumour
- Abscess
What are the differential diagnosis for a spinal cord lesion with a subacute onset of limb weakness?
- MS
- Tumour
- Transverse myelitis
What are the differential diagnosis for a nerve root lesion with a subacute onset of limb weakness?
- Guillain-Barre syndrome
2. Poliomyelitis
What are the differential diagnosis for a neuromuscular junction lesion with a subacute onset of limb weakness?
- botulism
2. tetanus
What are the differential diagnosis for a spinal cord lesion with a chronic onset of limb weakness?
- Spinal canal stenosis
2. Vitamin B12 deficiency
What are the differential diagnosis for a peripheral nerve or nerve plexus lesion with a chronic onset of limb weakness?
- DM
2. Vasculitis
What are the differential diagnosis for a neuromuscular lesion with a chronic onset of limb weakness?
- Myasthenia gravis
- Lambert-Eaton syndrome
- Myositis
What key points must be covered in history of limb weakness?
- time of onset
- speech or visual disturbances
- headache?
- seizure or loss of consciousness?
- neck or back pain?
- trauma to head in last few months?
- RF for stroke or TIA
Why is it important to know the time of onset?
stroke window to administer thrombolysis: only 4.5hr after onset of symptoms
What would limb weakness and deficit in speech or vision suggest?
problem in brain rather than spine or PNS
Is a headache usual in stroke or TIA?
No