Neuropathy

Question 1

What is neuropathy

Answer 1

a condition that involves damage or dysfunction of the peripheral nerves

Question 2

What are the types of neuropathy

Answer 2

1. peripheral neuropathy
2. diabetic neuropathy
3. autonomic neuropathy
4. cranial neuropathy
5. focal neuropathy

Question 3

what can cause peripheral neuropathy

Answer 3

diabetes, alcohol abuse, infections, toxins and certain medication

Question 4

What nerves does autonomic neuropathy affect

Answer 4

nerves that control involuntary bodily functions
(HR, BP, digestion, bladder function)

Question 5

give an example of a focal neuropathy

Answer 5

carpal tunnel syndrome

Question 6

list some neuropathic symptoms

Answer 6

1. tingling or numbness
2. burning or shooting pain
3. loss of sensation.
4. muscle weakness or atrophy
5. coordination problems
6. autonomic symptoms
7. persistent pain/hyperalgesia

Question 7

what is the somatosensory nervous system responsible for

Answer 7

transmission and perception of touch, temperature, proprioception and nociception (pain)

Question 8

What body parts do somatosensory neurons innervate

Answer 8

skin, visceral organs, ligaments, tendons, bone and muscle

Question 9

In what categories are neurons in the somatosensory system organised

Answer 9

axon size, myelination and receptor expression

Question 10

name the three major classifications of somatosensory neurons

Answer 10

Aα/β fibres
Aδ fibres
C-fibres

Question 11

Distinguish between Aα/β fibres, Aδ fibres and C-fibres in terms of diameter

Answer 11

Aα/β fibres - large diameter
Aδ fibres - medium
C-fibres - small

Question 12

distinguish between Aα/β fibres, Aδ fibres and C-fibres in terms of myelination

Answer 12

Aα/β fibres - heavily myelinated
Aδ fibres - moderately myelinated
and C-fibres - and unmyelinated

Question 13

distinguish between Aα/β fibres and C-fibres in terms of activation threshold

Answer 13

Aα/β fibres - low activation threshold
C-fibres - high activation threshold

Question 14

What signals do Aα/β fibres conduct

Answer 14

mechanosensitive and proprioceptive afferent signals

Question 15

What signals do Aδ fibres conduct

Answer 15

afferent signals regarding pain, temperature and some touch receptors

Question 16

What signals do C-fibres conduct

Answer 16

afferent signals regarding temperature, pain (nociceptive) and itch

Question 17

Which fibres are considered polymodal?

Answer 17

C fibers

Question 18

What is the term for transmission of pain

Answer 18

nociception

Question 19

What areas of the brain are recognized as being responsible for the integration of nociceptive input

Answer 19

sensory cortices
limbic system

Question 20

what neurotransmitter is released at synapse in regards the central pain integration

Answer 20

substance P, glutamate and CGRP (Calcitonin gene-related peptide)

Question 21

What two factors is pain characterized by

Answer 21

time (acute vs chronic)
and cause (nociceptive, inflammatory and neuropathic)

Question 22

When does acute pain become chronic

Answer 22

following 3 months

Question 23

Define hyperalgesia

Answer 23

exaggerated response to noxious stimulus

Question 24

define allodynia

Answer 24

painful response to a non-noxious stimulus

Question 25

List the treatment options for pain

Answer 25

1. Pharmacotherapy
2. Physiotherapy and rehabilitation
3. cognitive behavioral therapy
4. repeated injections
5. surgery

Question 26

What are the two pathways by which pain is endogenously modulated

Answer 26

1. descending neural inhibition
2. gate control theory

Question 27

Define neuropathic pain

Answer 27

pain arising as a direct consequence of a lesion or disease affected the somatosensory system

Question 28

What symptoms are associated with neuropathic pain

Answer 28

1. paresthesia
2. dysesthesia
3. burning/freezing sensations
4. electric shock
5. motor deficits
6. secondary symptoms (e.g., frozen shoulder)

Question 29

Explain the mechanism of neuropathic pain - peripheral sensitisation

Answer 29

1. ectopic/spontaneous discharge
2. alterations in ion channel and membrane bound receptor expression
3. collateral sprouting of neurons

Question 30

Explain the mechanism of neuropathic pain - central sensitization

Answer 30

1. spinal innervation reorganization
2. changes in pain inhibitory pathways
3. structural changes in pre and post synaptic neural membranes