Intro to Pain + Classification

Clinical questions to ask when taking subjective hx

• Co-existing conditions

• Previous injuries

• Other stuff going on in life (biopsychosocial)

• Aggravating activities

• Emotional component

• Beliefs about pain

• Lvl of fxn

• Tissue damage NOT EQUAL to pain

Pain definition

Unpleasant sensory + emotional experience associated w/ or resembling that associated w/ actual or potential tissue damage.

Tells us person’s experience

• Thoughts can trigger pain

• It’s personal, influenced by biopsychosocial

• Cannot be understood thru tissues alone

• Protective but also a barrier

• It is real and experienced despite unable to describe it

NS amplify or reduce nociceptive signalling

Is maladaptive

Nociception

Neural process of encoding noxious stimuli (potentially tissue-threatening). NS detected potential threat.

Triggers:

• Protective reflex: move hand away

• Autonomic response: HR, BP

PAIN NOT IMPLIED

• Can occur w/o pain

• Pain can occur w/o nociception

Transmitted thru NS, contributes to pain, butNOCICEPTION ≠ PAIN!

Pain classification systems

Time

Mechanism

Diagnosis

Body site/organ system

Etiology

Acute pain

Pain lasting < 3 mos

Chronic Pain

Pain lasting > 3 mos

> 1 yr chronic pain has a nociplastic component (even if it started as secondary pain).

Nociceptive pain

• Pain from damage or disease or non-neural tissue

• Physical damage

• i.e. skin, bone, mm, visceral organs

• PAIN IS A SYMPTOM!

Typically acute.

Neuropathic pain

Pain from damage or disease of the SOMATOSENSORY nervous system

i.e. MS

Pain is a symptom

Nociplastic Pain

• Pain from dysfunction of the somatosensory nervous system

• Pain is a disease

• i.e. Fibromyalgia

• NO DAMAGE, DISEASE to the nerve

• Software problem. Laptop looks fine but app not working.

• Physiological not psychological

Chronic primary pain

• Pain is a disease in its own

• 1+ area

• > 3 mos duration

• Associated w/ emotional distress or fxnl disability (interferes w/ ADL or social roles)

• Cannot be better accounted for by another condition

• NOT secondary to tissue damage/disease

i.e. Nociplastic,pain in bones/joints/mm/soft tissues w/ no damage/disease. NOTHING ON MRI OR XRAY. Non specific LBP

Chronic secondary pain

Pain is a SYMPTOM of another disease [tissue damage or disease]

Pain @ first is a symptom (i.e. arthritis)

• Pain is secondary to tissue damage/disease

Chronic pain is a co-diagnosis w/ underlying disease when pain becomes a problem on its own

• Pain is its own diagnosis

Can be nociceptive OR neuropathic

i.e. Arthritis, pain in bones/joints/mm/soft tissues due to damage/disease. LBP from stress fx or arthritis. Nociceptive.

Multi-dimensional Pain Classification

Where pain is

How long: acute, chronic, sub acute, recurrent

Cause: i.e. cancer-related.

Physiological mechanism: nociceptive, nociplastic, neuropathic

ICF Model

• Bodily fxn/structures: impairments in ROM

• Activities: limits in walking, stair climbing, gait

• Participation: work/sport

  • Environmental factors and personal factors

Nociception + Pain Main Points

Not all nociception results in pain

Not all pain is a result of nociception

Pain is the result of nociception → nociceptive pain