Week 2 (Pain)

Question 1

Define pain

Answer 1

An unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage

Question 2

What is a noxious stimuli?

Answer 2

A stimulus that is damaging or threatens damage to normal tissues

Question 3

What are nociceptors?

Answer 3

High threshold sensory receptor of peripheral somatosensory nervous system that is capable of transducing and encoding noxious stimuli

Question 4

What is peripheral sensitisation?

Answer 4

Increased responsiveness and reduced threshold of nociceptive neurons in peripheral tissues

Question 5

What is primary hyperalgesia?

Answer 5

Increased pain from a stimulus that normally provokes pain in the area of injury

Question 6

What is central sensitisation?

Answer 6

Increased responsiveness of nociceptive transmission neurons in the CNS to their normal or sub-threshold afferent input

Question 7

What is secondary hyperalgesia?

Answer 7

Spread of pain hypersensitivity beyond the area of tissue damage so that adjacent non-damaged tissue is tender, due to sensitisation of CNS

Question 8

What is alloydnia?

Answer 8

A non-noxious mechanism or thermal stimulus is painful

Question 9

Classification: Nociceptive pain

Answer 9

Pain that arises from actual or threatened damage to non-neural tissue and is due to activation of nociceptors (i.e. a normally functioning nervous system)

Question 10

Examples of nociceptive pain

Answer 10

Bee stings, sprains, fractures, burns, bumps, bruises, inflammation, tumours

Question 11

Classification: Neuropathic pain

Answer 11

Pain caused by a lesion or disease of the somatosensory nervous system (i.e. an abnormally functioning nervous system)

Question 12

Examples of neuropathic pain

Answer 12

Sciatica, injury, spinal cord damage, nerve compression, phantom limb damage, carpal tunnel syndrome

Question 13

Classification: Nociplastic pain

Answer 13

Pain that arises from altered nociception despite no clear evidence of actual or threatened tissue damage causing the activation of peripheral nociceptors or evidence for disease or lesion of the somatosensory system causing the pain

Question 14

Examples of nociplastic pain

Answer 14

Fibromyalgia, complex regional pain syndrome, chronic low back pain, irritable bowel syndrome and bladder pain syndrome

Question 15

What happens at the signal generator

Answer 15

Nociceptors detect a noxious stimuli and chemical substances activate and sensitise nociceptors

• Peripheral sensitisation
• Primary hyperalgesia

Question 16

What happens at the amplifier

Answer 16

Mechanisms at the signal generator result in central sensitisation. Nociceptive input can cause changes in function and structure in the dorsal horn leading to amplification of signal transmission system and pain hypersensitivity.

• Secondary hyperalgesia
• Allodynia

Question 17

What happens at the gain setter

Answer 17

Descending pathways from the brainstem to the spinal cord can modulate nociceptive processing and the experience of pain. Descending pain facilitatory and inhibitory systems function together to maintain a baseline however injury can result in dysfunction of pain inhibition and facilitation is always on. Descending modulation dysfunction can also happen in those with chronic pain where there is increased patterns of neuronal activation in pain-related cortical areas.

Question 18

What can physiotherapists do to help with pain?

Answer 18

• Restore normal input to sensory nervous system
• Activate inhibitory pathways in the spinal cord and higher brain setters
• Promote positive neuroplastic changes to normal neural processes involved with pain experience