Pain Midterm

Pain definition

an aversive sensory and emotional experience, typically caused by, or resembling that caused by, actual or potential tissue damage

6 notes about pain

1. Pain is always subjective

2. Pain is different than nociception

3. Pain is learned through life experiences

4. A person’s report of pain should be accepted

5. Pain is usually protective, but experience of pain could harm function and/or social/psychological well-being.

6. Pain may be experienced by humans and non-human animals.

What things come together to give a person their pain experience in the biopsychosocial model?

1. Environment – stimulus

2. Emotions

3. Expectations

4. Genetics

5. Memories – can be protective or create threat in certain contexts/experiences

6. Sensory input: nociception!

Ask me 3 tool quiestions

3. What is my main problem?

4. What do I need to do?

5. Why is it important for me to do this?

^to figure out how much your pt knows about their overall health

red flags

Signs/symptoms that may indicate more serious/sinister pathology

orange flag

psychiatric symptoms

yellow flag

psychology, personality related

blue flag

work/job related

black flag

societal factors

depression screening tool

PHQ-2

PHQ-2 cutoff

yes on any question = significant

FABQ cutoff

FABQ-PA >15

FABQ-W >34 (poor prognosis of return to work)

PCS cutoff

>30/52

TSK cutoff

>37/68

GAD-2 cutoff

>3 pts

GAD-7 cut off

>10 pts

PSFS cutoff

MDC - 3 pt change

anxiety disorder screening tool

GAD-2

GAD-7

pain catastrophizing outcome measure

PCS

kinesiophobia outcome measure

TSK

what are the key pain science principles expressed in the NPQ-R

1. CANNOT have pain and not know it!

2. Pain is NOT a sensation, receptors detect chemical, temperature, and mechanical info (there are NO PAIN RECEPTORS). Pain is an alarm.

3. “Hurt does not equal harm” Pain does not only occur when you are injured or at risk of being injured.

4. When body is injured, receptors convey ‘danger’ messages to your SC. Nociceptors transmit “danger” messages to SC.

5. Special nerves in your SC convey “danger” messages to your brain.

6. Nerves adapt by increasing their resting level of excitement. Nerves/nociceptors can become sensitized or can wake up. Can wake up their neighbors so the alarm system becomes more sensitive.

7. Chronic pain does NOT mean that an injury hasn’t healed properly. Hurt does not equal harm.

8. Worse injuries do NOT always result in worse pain. Pain relies on context. Ex: red light – patients felt more pain.

9. CNS can INHIBIT or FACILITATE.

10. Pain does not always mean you are injured. Or you can be injured and not have pain.

11. Pain depends on the environment/context.

12. The pain decides when you will experience pain. “Pain is in the brain.”

what is Pain neuroscience education (PNE)

1. Use of stories and metaphors to teach about pain

2. “Pain treatment” > move towards living without pain.

3. Based on the biopsychosocial model of pain

4. Depends on the skill of the clinician teaching it.

PNE is NOT

1. Not just advise movement despite pain

2. Not cognitive behavioral therapy.

3. Not cognitive/behavioral advice

4. Not a denial that nociceptive input can contribute to pain as an output.

PNE metaphors

1. “Alarm system”

2. Pain vs function

3. Envelope of function (avoiding boom/bust)

Can you describe the narrative review findings from Bunzli et al., 2023 regarding patient beliefs/narratives and pain and function for individuals with knee OA?

Broken machines narrative is impairment focused while an active bodies narrative is participatory focused.

placebo definition

1. I shall please

2. Causes positive effects

3. Images of STRENGTH

4. Body FUNCTION

5. Focus on ABILITY

Nocebo definition

1. I shall harm

2. Causes negative effects.

3. Images of WEAKNESS, PAIN

4. Body ILLNESS

5. Focus on DISABILITY

Why does AAOMPT oppose the use of the term degenerative disc disease

Recent evidence highlights the potential negative impact these diagnostic labels can have on patient outcomes. Relying on diagnostic anatomical labels to describe natural age-related changes, to guide interventions, and to inform activity recommendations can adversely affect patient outcomes”

lateral spinothalamocortical pathway

transmits sensory/discriminative aspects of pain

• where

• what

• how strong

medial spinothalamocortical pathway

transmits emotional/affective aspects of pain

• affect

• memories

• emotions

wide dynamic range neurons

register reponses that are noxious and non-noxious

1.        Majority of lateral system neurons

2.        Respond to noxious and non noxious stimuli

3.        Increased spontaneous firing rates in elevated pain states/processing models

acute pain

1.        Known MOI <3 months duration

2.        Proportional to tissue load/stage of healing

3.        Primarily “nociceptive” mechanism

4.        Protective/adaptive

5.        Have central INHIBITION

• Periaqueductal gray

• Rostroventromedial medulla

• Parabrachial nucleus

• Dorsal reticular nucleus

chronic pain

1.        MOI variable >3 months duration

2.        Disproportionate to tissue load/stage of healing

3.        Primarily “nociplastic” mechanism

4.        “disease state”/maladaptive

5.        Increased WDF firing

6.        Loss of inhibitory interneurons

7.        Reduced central inhibition – so central FACILITATION

• Amplified response to peripheral input

• Longer response duration

• “hyperexcitability”

8.        Cortical reorganization

What factors may predict the transition from acute to chronic pain? Why might these be important to identify (and HOW might you identify them in your PT evaluation)?

Dyesthesia

An unpleasant abnormal sensation, whether spontaneous or evoked (ex: allodynia and hyperalgesia are dysesthesias)

paresthesia

An abnormal sensation, whether spontaneous or evoked

anesthesia

absence of sensation

hypoaesthesia

decreased sensitivity to stimulation

hyperaesthesia

increased sensitivity to stimulation

allodynia

pain caused by a stimulus that does not normally provoke pain

hyperalgesia

increased pain from a stimulus that normally provokes pain

peripheral sensitization

Increased responsiveness and reduced threshold of nociceptive neurons in the periphery to the stimulation of their receptive fields

central sensitization

Increased responsiveness of dorsal horn (spinal cord) neurons (e.g., “wind up” or temporal summation).

conditioned pain modulation

The ability of descending pain inhibitory mechanisms (central) to effectively inhibit pain following a painful stimulus

temporal summation

Increased pain response to repetitive noxious stimuli

primary hyperalgesia

1.        Increased responsiveness of primary afferent nociceptive neurons following tissue injury and related persisting pain (happens as early as a few days)

2.        Due to PERIPHERAL sensitization

3.        Protective/adaptive response from nervous system to prevent further damage/use of area of tissue injury

Secondary hyperalgesia

1.        Increased responsiveness of dorsal horn neurons localized in the spinal segments of the primary source of nociception

2.        Due to CENTRAL sensitization

3.        Could help explain spreading pain

homosynaptic facilitation

1.        Repeated peripheral input sensitizes dorsal horn projection neurons in nociceptive pathway

2.        Process proprosed to contribute to PRIMARY HYPERALGESIA

heterosynaptic facilitation

1.        Intraneuronal facilitation of adjacent spinal projection pathways

2.        May explain expansion of pain beyond the area of insult/injury

3.        Process proposed to contribute to SECONDARY HYPERALGESIA

Nosy neighbors

nociceptive pain definition

Pain that arises from actual or threatened damage to non-neural tissue and is due to the activation of nociceptors. Aka “tissue damage”

nociceptive description

1.        Proportional

2.        Provokable

3.        Periodic

4.        Predictable

nociceptive patient outcome measures

1.        VAS (MCID:20)

2.        NPRS – numeric pain rating scale (MCID: 2)

neuropathic pain definition

Pain caused by a lesion or disease of the somatosensory nervous system. Can be to PNS or CNS but must be part of somatosensory system (cerebellum lesion would not qualify). aka “nerve injury”

neuropathic pain description

1.        Subjective/history (of nerve injury)

2.        Sensory deficits (dermatomal pattern)

3. Stretching the nerves (provokes symptoms

neuropathic patient outcome measures

1.        S-LANSS - self-reported leeds assessment of neuropathic symptoms (> 12 – likely neuropathic component)

2.        Pain DETECT (>19 – likely neuropathic component)

nociplastic pain definition

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. Aka “sensitization”

nociplastic pain description

1.        Disproportionate pain

2.        Disproportionate agg/ease factors

3.        Diffuse pain (or palpation tenderness)

4.        Distress (psychosocial issues)