pain pathology Flashcards
population affected by pain
116 million in US
up to 20% of all primary care visits- chronic pain
26% of adults have had pain for >3 months and 1/3 report it as disabling.
allodynia
pain due to a stimulus that does not normally provoke pain
hyperalgesia
increased pain from a stimulus that is normally painful
hyperesthesia
increased sensitivity to stimulation, excluding the special senses (includes both allodynia and hyperalgesia
hyperpathia
painful syndrome characterized by an abnormally painful reaction to a stimulus, especially a repetitive stimulus, as well as an increased threshold (augmented response to any sensory stimuli)
causalgia
syndrome of a sustained burning pain, allodynia, hyperpathia after a traumatic nerve lesion, often combined with vasomotor and sudomotor dysfunction (such as diabetic autonomic neuropathy) and later trophic changes
analgesia
absence of pain in response to stimulation that is painful
dysesthesia
unpleasant abnormal sensation, whether spontaneous or provoked
paresthesia
abnormal sensation, whether spontaneous or evoked
nociceptive pain
nociceptive pain is pain in the muscles, tissue, ligaments, soft tissue; modulates from physical pain or damage to the body
response to an immediate noxious stimulus; results in inflammatory pain
neurogenic pain
damage or disfunction of the nervous system
two types: central neruogenic pain and peripheral neruogenic pain
central neruogenic pain
injury to CNS (spinal cord- brain)
burning, aching, prickling, hyperalgesia, allodynia
peripheral neurogenic pain
injury to the PNS (spinal cord- nerve endings) paresthesia, dysesthesia, pain
fibromyalgia
widespread MSK pain and fatigue accompanied by tenderness of the muscles and adjacent soft tissue
effects mostly females
triggered by trauma, surgery, infection, or psychological stress
myofascial pain syndrome
persistent, deep aching pain in muscle; characterized by well-defined higly sensitive tender spots “trigger points”
postural stress syndrome
postural malalignment produces chronic muscle lengthening and/or shortneing and stress on tissues
movement adaptation syndrome
habituated movement dysfunction leading to muscle strain and pain
psychosomatic pain
origin is related to mental or emotional factors
referred pain
pair arising from deep visceral tissue that is felt in a body region remote from the site of origin
free nerve endings
most abundant type of nerve ending
near blood vesselse between epithelial layers of skin
merkels disc
tactile end organ, abundant in fingertips and whiskers
krause’s end bulb
speacialized sensory nerve ending in skin, temperature sensation
meissner’s corpuscle
cutaneous nerve ending responsible for transmitting the sensation of fine touch and vibration.
Pacinian corpuscle
encapsulated ending of s sensory nerve that acts as a receptor for pressure and vibration
ruffini corpuscle
found in superficial dermis of both hairy and glaborour skin, sense low-frequency vibration or pressure
fast, localized pain
transmitted over thinly myelinated A delta fibers; processed in dorsal horn
slow pain
transmitted over small diameter; unmyelinated C gibers; processed in dorsal horn
transduction of pain
process by which a painful physical or chemical stimulus is transformed into a signal that can be carried via transmission to CNS and perceived as pain;
changin external action into neruological signal
gate control theory
modulation of pain happens in brain stem; gate open- pain signal is let through
gate closed- pain signal restricted
(chronic pain- gate stays open)
pain modulation C fibers and A beta fibers
painful stimuli travel on C fibers, but A beta fibers travel faster and can inhibit the full response of the nervous system (before the c fibers)
ex) hitting your shin on something and then rubbing it with your hand immediately after, inhibits full sensation delivered by C fibers
endogenous opioids
endorphins and enkephalins
can depress pain transmission at various presynaptic locations
another way to modulate pain
referred pain for heart, stomach, kidney
heart: Left chest, arm
stomach: center of back, center of abdomen near xiphoid process
kidney: Both lower quadrants into legs
sensory aspects of pain (pathway)
detection, localization, intensity, stimulus identification
first pathway: pain signal comes from anywhere in body and activated the anterior cingulate cortex of the brain which is associated with teh perception of pain
affective aspects of pain (pathway)
(second pathway): travels to the prefrontal cortex and nucleus accumbens which are associated with motivation and emotion.
nagging, uncomfortable, excruciating role of mood change
pain threshold vs pain tolerance
threshold: minimum point at which something causes you pain
tolerance: maximum amount of pain you can tolerate
central sensitization vs peripheral sensitization
central: amplification of neural signal associated with chronic pain- hypersensitivity
peripheral: reduced pain threshold
medical management of chronic pain
lab tests, diagnostic nerve blocks to help determine the structure involved
NSAIDs, ms relaxors, opiods, topicals
