L21 - somatosensory disorders

Question 1

fast conducting pathway

Answer 1

dorsal columns

Question 2

slow conducting pathway

Answer 2

spinothalamic

Question 3

myelinated fibres

Answer 3

dorsal columns

Question 4

unmyelinated fibres

Answer 4

spinothalamic

Question 5

Myelitis

Answer 5

inflammation of the spinal cord

Question 6

consequence of lesion to medulla

Answer 6

DCML pathway is spared as here is where crossing over occurs
spinothalamic fibres are in the middle of the medulla and so you lose this (pain and temperature sensation) (this is contralateral to the side of the lesion)

Question 7

anterior spinal artery syndrome - what is it?

Answer 7

occlusion of the anterior spinal artery and infarction of the spinal cord

Question 8

anterior spinal artery syndrome symptoms

Answer 8

loss of blood supply to this region affects spinothalamic tract and motor functions from this area

Question 9

where is the lesion: loss of sensation of the left side of body including face to all modalities - accompanied by pain in the left sided limbs

Answer 9

stoke to RHS of thalamus (this is where both pathways are travelling together contralaterally) = right thalamic infarct

Question 10

lacunar stroke

Answer 10

stroke affecting small perforating vessels

Question 11

dysgraphaesthesia

Answer 11

if you write a number on the hand, you cannot recognise it

Question 12

hemisensory neglect

Answer 12

do not perceive that side of the body as their own

Question 13

result of stroke in the parietal cortex

Answer 13

• dysgraphaesthesia
• hemisensory neglect
• R/L confusion
• no numbness

Question 14

syringomyelia

Answer 14

expansion of the spinal canal

Question 15

what fibres does syringomelia affect first

Answer 15

spinothalamic

Question 16

how to treat syringomyelia

Answer 16

surgically to open up and release pressure

Question 17

how to recognise syringomyelia on CT scan

Answer 17

white slit going down the cord = inflated central canal = syrinx

Question 18

causes of peripheral neuropathy

Answer 18

• diabetes mellitus
• autoimmune disease
• toxins such as alcohol
• vitamin deficieny
• paraneoplastic
• chronic kidney / liver disease
• inherited

Question 19

Romberg test

Answer 19

stand with feet together and closes eyes - if no proprioception, they will fall

Question 20

subacute combined degeneration cause

Answer 20

b12 deficiency

Question 21

distribution of peripheral neuropathy

Answer 21

glove and stocking

Question 22

cause of pure sensory stroke

Answer 22

thalamic infarct

Question 23

causes of dissociated sensory loss

Answer 23

lesions in the spinal cord or brainstem