Intro to Persistent Pain

Question 1

How many people in the world experience chronic pain

Answer 1

1/4 of people in the world

Question 2

Why is the pain epidemic happening?

Answer 2

• Industrial Revolution
  ◦ Machinery started doing the work for us, so we became more sedentary
  ◦ Amount of back pain is staying the same but disability is increasing

Question 3

Purposes of pain

Answer 3

• protection/survival
• create vigilance
• shift salience
  *** ultimately the goal is to create some sort of behavior response to minimize damage/threat and enhance survival

Question 4

does structural pathology paradigm work for chronic pain?

Answer 4

nope
only acute

Question 5

mature organism model

Answer 5

• brain: “central scrutinizing center”
• sample from the tissues as well as the environment
• information is integrated to create response for the best advantage

Question 6

what is pain produced by?

Answer 6

THE BRAIN

Question 7

nociception

Answer 7

• The process by which information about actual or potential tissue damage is relayed to the brain
• thermal, chemical, mechanical

Question 8

does nociception always equal pain?

Answer 8

no

Question 9

does damage always equal pain?

Answer 9

no

Question 10

Normal tissue healing

Answer 10

• tissues will undergo relatively predictable stages of healing over time
• pain experience is poorly correlated to those stages of healing
• many people suffer from significant pain, yet no injury or disease process can be identified

Question 11

pain lasting more than a couple of months has a greater potential to be…

Answer 11

a pain problem

Question 12

neuroplasticity

Answer 12

• nervous systems ability to change structure and function
• normal ongoing state throughout the lifecycle

Question 13

adaptive neuroplasticity

Answer 13

purposeful, protective

Question 14

maladaptive neuroplasticity

Answer 14

CNS is protecting us from things not threatening and damaging

Question 15

structural changes in learning

Answer 15

• increased gray matter volume and density in task-specific areasf

Question 16

functional changes in learning

Answer 16

• reorganization/increased activity
• motor
  -sensory
• cognitive
• emotional

Question 17

expectations drive…

Answer 17

outcomes

Question 18

what drives expectations

Answer 18

beliefs

Question 19

who has the strongest influence on attitudes and beliefs

Answer 19

healthcare providers

Question 20

PTs with high fear avoidance and higher biomedical orientation….

Answer 20

• Delay return to work
• Delay return to activity
• Tendency to not limit number of sessions
• CLBP approached from a strong biomedical model without addressing psychosocial factors
• Lack of confidence in biopsychosocial model
• Dislike treatment complicated cases
• Feel psychosocial assessment is not their role

Question 21

PTs tend to….

Answer 21

• Assess their perception of patient’s willingness to engage in self management
• Engage more actively with patients whom we perceive to be more engaged

Question 22

words that harm

Answer 22

• Showing pictures/models –> explain what is happening but also explain that tissues heal
• Misunderstood medical terms/diagnoses
• Literacy skills – strong predictor of health
• Internet usage by patients seeking answers

Question 23

words to avoid/alternatives

Answer 23

• chronic degenerative changes –> normal age changes
• instability –> needs more strength/control
• bone on bone –> narrowing
• paresthesia/hyeresthesia –> altered sensation
• disease –> condition

Question 24

optimism

Answer 24

• Protects against anxiety
• Associated with reduced pain intensity and physical
  symptoms related to open heart surgery
• Significant predictor of positive health outcomes

Question 25

convey to patients:

Answer 25

• Inflammation is normal
• Immune responses are normal
• Sensitivity as normal and learning
• Normal healing

Question 26

therapeutic alliance

Answer 26

relationship between the patient and the provider

Question 27

descending inhibition of pain from higher cortical centers

Answer 27

• anterior cingulate cortex: escape/avoidance behaviors
• insular cortex
• pre-frontal cortex
• amygdala
  ** send input directly to the PAG/RVM

Question 28

descending inhibition of pain - PAG-RVM pathway

Answer 28

• electical stimulation –> inhibits spinal neurons that respond to noxious stimuli
• analgesia in rats, cats, and humans
• Efferent projections from RVM to SC are involved in inhibition of nociception

Question 29

Descending inhibition of pain - neurons in the RVM

Answer 29

• On cells: facilitation/sensitization
• Off cels: inhibition
• neutral cells can alter their phenotype after tissue injury; can develop on-like or off-like activity after inflammation

Question 30

neurotransmitters - opioids/morphine (RVM)

Answer 30

• excites off cells
• suppresses on cells

Question 31

neurotransmitters - norepinephrine

Answer 31

• dorsolateral pontine tegmenjtum is primary source of NE in spinal cord
• decreases activity of spinal nerves
• causes anticociception
• reduces hyperalgesia

Question 32

descending inhibition of pain - somatosensory Cortex

Answer 32

• sends fibers to spinal cord directly via CST and indirectly via PAG
• inhibits neurons in STT
• presynaptic inhibition of 1st order afferents

Question 33

descending inhibition of pain - motor cortex

Answer 33

stimulation may reduce pain in patients with neuropathic pain

Question 34

descending inhibition of pain - descending noxious inhibitory controls (DNIC)

Answer 34

• reduces hyperalgesia/ pain
• reduces DH neuronal activity
  -mechanism not well understood
• decreased efficiency of this pathway in patients with chronic pain

Question 35

other areas in the brain that inhibit pain/nociception when activated

Answer 35

• Hypothalamus
• Thalamus
• Somatosensory cortex
  Relay directly or indirectly through
• Prefrontal cortex
  the RVM
• Amygdala
• Reticulospinal Tract
• all relay directly or indirectly through RVM

Question 36

systems affected by placebo

Answer 36

• pain
• motor performance
• autonomic and CV
• endocrine
• immune