Pain Assessments and Treatments

neuropathic pain

pain from damage to neurons of either the peripheral or central nervous system
- can be caused by dysfunction of axons, myelin, or both
- can be permanent damage!!!

multifocal

neuropathic pain can be focal or ____, in that pain can be felt right around the neuron that is damaged or far away from the neuron that is damaged

radiculopathy

disease of the spinal nerve roots

diabetes

a cause of neuropathic pain
- stocking/glove distribution
- mononeuropathy (damage in one area)
- any CN or peripheral nerve can be impacted
- sensorimotor deficits (balance, proprioception)
- painful paresthesias (alterations of sensory perceptions, pins/needles > tingling)

CN III and femoral/sciatic nerves

which nerves are most commonly damaged in diabetes with neuropathic pain?

mechanical injury

a cause of neuropathic pain
- compression, traction, laceration

CRPS

intense local burning pain accompanied by edema, sweating, and changes in skin blood supply (redness/pallor)
- type I: reflex sympathetic dystrophy (RSD)
- type II: causalgia

neuropathic pain causes

diseases (HIV, CMV, shingles, lime disease, HepB)
toxic substances
malnutrition
autoimmune disorders (RA, lupus)
genetics
cancer
phantom limb
stroke
trigeminal neuralgia
MS
dry eyes
SCI

PainDetect questionnaire

what assessment is used to assess neuropathic pain

neural hypersensitivity

commonly seen with the following diagnoses:
- CRPS
- fibromyalgia
- chronic LBP
- chronic headaches
- chronic TMJ pain
- IBS
- Chronic fatigue syndrome
- pelvic girdle pain syndrome
- cancer pain

central sensitization inventory

how is neural hypersensitivity assessed?

pain catastrophizing

evidence for cortical/limbic system influence on pain perception and experience

pain catastrophizing scale

how is pain catastrophizing measured?
- rated on a 0-4 scale

Pain Catastrophizing Scale

grade 6 reading level (wide range of patient populations)
adequate to excellent internal consistency
total PCS score > or equal to 30= clinically relevant catastrophizing

kinesiophobia

fear of movement
50-70% of people with chronic pain
high fear of movement = disabled

quality of life

fear of movement is associated with higher pain intensity, disability, and lower ____ __ ____

improving

kinesiophobia does NOT prevent us from _____ pain

neck

the tampa scale for kinesiophobia contains good psychometric properties for LBP, fibromyalgia, and ___ pain

pharmacologic treatment

first line- antidepressents and anticonvulsants
- antidepressents target NTs associated w/ pain control (decrease pain signals)
- anticonvulsants block Ca2+ channels
second line- tramadol, opioids
third line- cannabinoids (THC)

non-pharmacologic treatment

transcranial magnetic stimulation
implanted stimulator (spinal cord)- stimulates pain suppression systems
dorsal rhizotomy
cognitive behavioral therapy
relaxation/meditation/hyponosis
accupuncture (placebo effect)

pain

the patient often doesn't understand why they have ____ if no tissue damage is present
- can increase fear

short educational strategy

initial explanation of pain at first patient encounter
- around 5 minutes
- brief follow ups (around a minute) at subsequent appointments

long educational strategy

more in-depth discussion
physiology and pathophys of pain
- pain without injury/tissue damage
- treatments targeted at physiological mechanisms
assign homework for patient to explore these mechanisms
- youtube videos

reassurance, de-medicalization, encourage activity

the 3 components of the short education strategy are

reassurance

pain is not dangerous

de-medicalization

patient is the expert
- put them in control

encourage activity

gradual return to pre-injury/pre-pain activities

exercise induced hypoalgesia

during and after exercise
- people have diminished sensitivity to pain
- pain threshold and tolerances increase

increased; decreased

high pain sensitivity is a predictor of _____ disability and _____ activity

graded motor imagery

helps to address deficits in left-right
discrimination often observed in individuals with chronic pain
activates mirror neurons
"visualizing movement"
- mirror therapy

decreases

TENS works via central mechanisms
i.e. it ____ the activity of dorsal horn neurons
- used with acute and chronic pain
- high and low frequency

reduction

TENS can result in complete ____ of secondary hyperalgesia (pain around the area of tissue damage)

partial

TENS can result in _____ reduction in primary hyperalgesia (pain in area with tissue damage) with high frequency but not low frequency TENS

segmental inhibition

decreased NTs that are released on 2nd order neuron
hyperpolarizes 2nd order neuron making it harder to get to threshold

increase

if you increase the frequency of TENS you ____ segmental inhibition

low frequency TENS

works through mu opioid receptors
Should NOT be used if patient has a morphine tolerance
- the mu opioid receptors are not as sensitive

high frequency TENS

works through opioid receptors
still effective in patients with morphine tolerance

tolerance

repeated use of TENS will cause _____, thus why parameters must be varied