Neurological weakness

Question 1

What can lower motor neurone disorders cause?

Answer 1

Weakness, wasting, reduced muscle tone, visible spontaneous contractions (fasciculations).
peripheral neuropathy (e.g., diabetes, B12); specifically of facial nerve: Bell’s palsy (affects whole side of face).

Question 2

What can upper motor neurone disorders cause?

Answer 2

Weakness, no wasting, increased muscle tone, no fasciculations. eg. stroke, multiple sclerosis, tumour

Question 3

Does the duration of the weakness give any clues as to the pathology?

Answer 3

minutes-hours = vascular
days-weeks = inflammation/infection
weeks-months = tumour
months-years = degeneration

Question 4

What are the neurological tests you can do to test if muscles are working (as cranial nerves control these and give an idea to neurological capacity)

Answer 4

-face,mouth, VII–facial nerve. Test=smile
- jaw, chewing, V-trigeminal nerve. Test =open your mouth
- tongue, XII hypoglossal nerve. Test: stick out your tongue (it will point to your weak side)
- swallowing, X - vagus. Test: swallow, cough, “aah” (uvula points away from weak side)
[IX - glossopharyngeal] Test: can you feel this?

Question 5

What is bulbar palsy?

Answer 5

bilateral impairment of function of cranial nerves V, VII, X and XI due to LOWER motor neuron lesion in the medulla
(or bilateral lesions of lower cranial nerves outside brainstem).
Symptoms – dysphagia (difficulty in swallowing), difficulty chewing,
nasal regurgitation, dysarthria (slurring of speech), choking on liquids
Signs – nasal speech (lacking in modulation and difficulty with all consonants), tongue atrophy with fasciculations, dribbling of saliva, weakness of soft palate (ask the patient to say “aah”)

Question 6

What is Pseudobulbar palsy?

Answer 6

bilateral impairment of function of cranial nerves V, VII, X and XI due to UPPER motor neuron lesion affecting the cortical pathways to the medulla.
Symptoms – dysphagia, dysarthria, difficulty chewing, choking
+ labile affect, uncontrollable laughing or crying Signs – speech is slow, thick and indistinct, tongue is small & stiff.

Question 7

What’s a neuromuscular disease?

Answer 7

Myasthenia gravis

Question 8

What’s a muscular disease?

Answer 8

muscular dystrophy

Question 9

What are the symptoms and signs of raised intracranial pressure?

Answer 9

 symptoms: nausea, headache
 General signs: vomitting, possible ↓GCS  Signs relating to BP:
bradycardia, increased systolic BP widened pulse pressure
 Others: Cheyne-Stokes breathing, papilloedema, dilated pupil/pupils

Question 10

What can cause raised intracranial pressure?

Answer 10

 Brain parenchyma  Interstitial fluid  Meninges  CSF

Question 11

What are the consequences of raised intracranial pressure?

Answer 11

1. Coning: Brainstem compression:
   Damage to vital respiratory and cardiac centres, can be fatal
2. Extradural haematoma
3. Subarachnoid haemorrhage

Question 12

What’s a stroke?

Answer 12

Sudden onset neurological signs / symptoms
Last for >24 hours
Due to a vascular cause 85% infarction (embolism / thrombosis) 15% haemorrhage

Question 13

What are the sources of emboli for a cerebral infarction?

Answer 13

Left atrium
Mural thrombus
Cardiac valves
Atherosclerosis (aorta and carotid)