Limb weakness

Question 1

What is ataxia

Answer 1

A clumsy limb

Question 2

Sudden onset (Seconds to minutes) limb weakness implies what cause?

Answer 2

Trauma (e.g. displaced fractures) or vascular insults (e.g. stroke/TIA)

Question 3

Subacute onset (hours to days) limb weakness implies what cause?

Answer 3

Progressive demyelination (e.g. Guillain-Barre syndrome, multiple sclerosis) or a slowly expanding haematoma

Question 4

Chronic onset (weeks to months) limb weakness implies what cause?

Answer 4

Slow growing tumour or MND

Question 5

Speech or visual disturbance indicates that the problem is where?

Answer 5

In the brain (not peripheral nerve or spine)

Question 6

Headaches are uncommon in TIA. A sudden onset headache that is terrible may indicate?

Answer 6

SAH

Question 7

A unilateral headache before limb weakness may indicate?

Answer 7

Hemiplegic migraine

Question 8

Gradual onset headache preceding limb weakness may indicate?

Answer 8

Subdural haemorrhage

Question 9

Guillan-Barre syndrome often is accompanied by pain where?

Answer 9

Back pain

Question 10

If there is neck or back pain, aside from Guillain-Barre syndrome, what else can we suspect?

Answer 10

Spontaneous disc prolapse or traumatic injury to the spine

Question 11

Describe the signs of an UMN lesion

Answer 11

Increased tone, reflexes, upgoing plantar (Babinski positive), clonus (sometimes)

Question 12

Describe the signs of a LMN lesion

Answer 12

Decreased tone, reflexes, wasting, fasciculations (sometimes)

Question 13

Language defects suggest pathology in the dominant hemisphere (usually left). Describe receptive and expressive dysphasia

Answer 13

Receptive dysphasia = problems in Wernickes area, can speak fluently but cannot comprehend

Expressive dysphasia = patient can comprehend speech and follow instructions. Cannot find words or speak fluently

Question 14

Attention deficits (e.g. ignoring half of their sensory world), where is the lesion?

Answer 14

Parietal cortex

Question 15

Complete blindness in one eye indicates a lesion where?

Answer 15

Optic nerve (e.g. optic neuritis)

Question 16

Homonymous hemianopia. Where is the lesion.

Answer 16

Lesion between optic chiasm and visual cortex

NB homonymous hemianopia may present similarly to visual neglect due to parietal cortex lesions

Question 17

If the eye deviates away from the weak side, where is the lesion?

If the eye deviates towards the weak side, where is the lesion?

Answer 17

Eye deviates away from weak side = cortical lesion

Eye deviates towards weak side = brainstem lesion

Question 18

In facial nerve palsy, how can you distinguish UMN lesion from LMN lesion

Answer 18

If forehead wrinkling and blinking is spared, this is an UMN

Question 19

What are the ddx for lesions in a cerebral cortex

Answer 19

Stroke (infarct or haemorrhage)
Cerebral mass (Eg tumour, abscess)
Hemiplegic migraine
Hypoglycaemia

Question 20

What does the anterior cerebral artery supply?

What about MCA

Answer 20

ACA = foot and leg

MCA = everything else (including face and arms)

Question 21

Lesion to the posterior parietal cortex can cause?

Answer 21

Contralateral hemineglect

Question 22

If someone presents with a suspected stroke within 4.5 hours of onset of symptoms, what should be done?

Answer 22

Non-contrast CT head.

4.5 hours = thrombolysis window

Question 23

Ischaemic strokes are more common than haemorrhagic strokes. How do you treat an ischaemic stroke?

Answer 23

If within 4.5 hour window of thrombolysis: Thrombolysis and anti-platelet therapy (aspirin)

If outside 4.5 hour window of thrombolysis: anti platelet (aspirin), VTE prophylaxis (LMWH & stockings), stroke unit

Question 24

On the stroke unit, what second line investigation should be done in a patient who has had a suspected (ischaemic) stroke?

Answer 24

Carotid doppler US: ?carotid artery atheroma cause of emboli

Echocardiogram: identified cardiac source of thrombus

Question 25

Which drug prophylaxis may benefit patients who have suffered from ischaemic stroke?

Answer 25

Daily antiplatelet (e.g. clopidogrel),daily statin and daily ACEi or diuretic

Question 26

When do you use anticoagulants and when do you use antiplatelets?

Answer 26

Anticoagulants (warfarin/rivaroxaban)- red clots - i.e. deep veins or fibrillating atria (VTE/AF)

Antiplatelets (aspirin/clopidogrel)- white clots - MI/primary ischaemic strokes

Question 27

If you suspect cord compression (bilateral weakness and sensory loss in legs), what should you do

Answer 27

Spinal MRI to confirm

Question 28

If a patient has bilateral weakness in legs, as well as eye problems, over a gradual time course - what could this suggest?

Answer 28

MS - it is a gradual demyelinating disorder of neurons

Consider doing a lumbar puncture, MRI and visually evoked potentials

Question 29

In spinal cord lesion, what functions are lost ipsilaterally and what functions are lost contralaterally

Answer 29

Ipsilaterally - power, vibration, proprioception and fine touch

Contralaterally - pain and temperature

Question 30

Proximal muscle weakness (in 1/2/3/4 limbs) may indicate NMJ weakness. Which conditions could this indicate?

Answer 30

Myasthenia gravis, Eaton-Lambert syndrome