Modalities Ch. 8 Flashcards
what is pain?
subjective
#1 reason an athlete seeks tx
physiological
modulates response to a pain inducing stimulus
types of subjective pain
emotional
psychological
social
why is pain physiological
it is associated w/ tissue damage
cause and effect types of pain
simple pain
response aimed at protecting and healing
simple pain can become chronic pain (> 3 months)
simple pain
acute pain
tissue damage
most sports-related pain
alarm system alerts brain to actual or potential tissue damage
how does pain protect and heal the body?
it signals the brain that there is something wrong
plays a role in initiating the healing processes
how can simple pain become chronic?
-% of pop. that suffers from chronic pain
untreated
incorrect treatment
20% suffer
consequences of chronic pain
depression decreased activity/disability atrophy loss of skill anxiety circulatory deficiency
how is pain described?
subjectively
-burning, sharp, achey, deep
we try to make it objective
-1-10 pain scales
nociception
ability to feel pain
nociceptors
specialized nerve endings that respond to stimulus - mechanoreceptors, thermoreceptors, chemoreceptors
how are nociceptors classified
by location
- cutaneous
- somatic
- visceral
which nociceptors are most common?
mechanical nococeptors (a-delta, force) polymodal nociceptors (C, heat, mechanical pressure)
function of A-delta fibers
pain transmission
crude touch
pressure
temperature
function of C-fibers
pain
touch
pressure
temperature
nociception vs. pain
nociception -specific neurophysiological activity pain -interpretation of nociception --subjective and emotional
impacts on pain
past pain experience
general life stress
heredity
personality differences
common noxious stimuli
mechanical - pressure directly on a nerve (swelling, muscle spasm)
thermal
electrical
chemical - mediators that are present when injured, bradykinin
pathway of pain
slam hand in car door
pain signal - chemicals released
chemicals signal receptor to generate a signal
signal travels up the arm on first-order neurons
transmit to the dorsal horn of the spinal cord
signals relayed to a second order neuron
neurons transmit the signal up the spinal cord
received at the thalamus
pain signal transmitted to the cerebral cortex by the third order neuron
pain signal is processed
pain terminology
perception threshold
-when it starts to hurt
tolerance threshold
-when someone acts on the pain
Specific Theory of Pain
specific nociceptors
specific nerve pathways
specific sensation
Pattern Theory of Pain
no existence of specific pain receptors
slow-conducting nerve fibers carry pain
fast-acting nerve fibers carry other sensations
normally, the fast-conduction fibers override the pain
under pathological conditions, the intensity of the stimulation in the slow system becomes much greater and dominates the fast system, resulting in pain
Pattern Theory of Pain flaw
too general - doesn’t account for receptor specialization
Gate Control Theory
specificity + pattern theory
operates at spinal level
proposes a gate mechanism
central control
gate mechanism
-pain and other sensory stimuli travel along both large and small nerve fibers
-both stimulate T-cells which pass onto brain
action system includes all responses to the pain
inhibitory mechanism located in the substantia gelatinosa
SG inhibits the T-cell
differential stimulation of SG cells
what types of pain do the large and small fibers carry?
large: sharp, stinging
small: dull, aching
how do large and small fibers stimulate the SG?
large: facilitates SG
small: inhibits SG
Gate Control Theory problems
does not account for phantom limb pain
cannot explain influence of drugs on pain
types of pain relieving drugs
morphine naloxone enkephalin endorphin serotonin
morphine function
blocks pain
- fills neurotransmitter sites
- neorutransmitter blocked
naloxene function
morphine antidote: reverses effects
enkephalin
- mixture of two peptides
- similar in shape and similar analgesic properties as morphine
- found in brain, spinal cord, gut
- half-life very short thus operates at spinal cord level
- block the gate by interfering w/ A-delta and C fiber signal transmission to T-cells
- released through non-painful sensory stimulus
- -sensory TENS, gentle massage
endorphin
- similar to…
- where is it produced?
- half-life
- where does it act?
- how does it work?
- how are they released?
endogenous molecule
similar to morphine
produced in pituitary and circulated through body
half-life = four hours
acts in several areas of CNS (including dorsal horn)
inhibits pain signal transmissions and decreases chemical irritants in CNS
may be released by acupuncture and intense exercise
serotonin
biochemical messenger and regulator
found primarily in CNS, GI tract, and blood platelets
mediates several physiological function, including neurotransmission
may influence pain perception via descending tract (brain to spinal cord), block signals from peripheral nociceptors
dopamine
neurotransmitter in extrapyramidal system of brain
important in regulating movement
may also be used to synthesize norepinephrine and epinephrin
affects brain processes ___________
opoids
endogenous opiates
term used to denote body’s internal pain killers such as enkephalin, endorphin, serotonin, and dopamine
bind to opiate receptors in the brain
operate in different parts of nervous system
effective for varying lengths of time
levels of pain control
level I: ascending influence pain control
level II: descending influence pain control
level III: beta-endorphin-mediated pain
level I: ascending influence pain control
traditional gate control pain relief theory
gating mechanism induce pain relief
TENS, massage, cryotherapy
level II: descending influence pain control
pain relief occurs in higher brain centers
release of enkephalin modulates pain
possible explanation for C-fiber activation relieving pain
ex.: acupuncture or noxious TENS
level III: beta-endorphin-mediated pain
prolonged stimulation of A-delta fibers
triggers the release of beta endorphins
longer term pain relief due to the 4hr half-life of endorphins
dimension of pain
social emotional psychological physiological therapy is an art
function of social, emotional, and psychological dimensions of pain
reasons why therapy doesn’t work
affect the rate of therapy
how to make a patient the owner of their pain
communication distraction education use it as a positive responsibility -pain meds. -treatment
when do we ignore pain
minimal chronic sore vs. pain denial inconvenient/annoying conditioning
when do we listen to pain
when it is significant interferes with everyday life visceral familiar -past experience
what does it mean to respect pain
understand when it needs attention knowing when to stop/continue -past experience -type of pain -understanding consequences
Dehne’s Spinal Adaptation Syndorme
afferent nociceptive impulses from traumatized tissue alter the integration of central nervous excitation at the spinal cord
-decreased response to volitional stimuli
-increased response to otherwise subliminal peripheral stresses
results in involuntary muscle action
alters repair
responds adversely to addition stress, favorably to reestablishing central control
nociceptive impulses from traumatized tissue inhibit motor function and tissue repair
voluntary activity can reestablish CNS control and prevent this inhibition
prolonged inactivity after injury will lead to neural inhibition that may become permanent
resetting central control
not enough to just get rid of the pain sensation
must also get rid of the effects of the pain
-reset the system
Chicago Plane Analogy
a tire blowout occurs during takeoff
the runway is shut down so the damaged plane and debris can be romoved
the runway reopens (pain removed)
however, thousands of passengers are stranded because of canceled flights (Chicago and elsewhere)
meetings must be rescheduled, which takes time after the reopening of the airport
resetting central control after injury
progression exercise
source of athletic injury pain
nociceptor pain -cause of most sports injury pain relay impulse to spinal cord nociceptor is stimulated by -injured tissue (mediator release) -edema pressure -stretching injured tissue -otherwise normal activity in a tissue that is sensitized from disuse after injury
source of athletic injury pain
neuropathic pain
-complex, chronic pain state accompanied by tissue damage to nerve fibers
occurs due to
-acute nerve damage
-disuse following injury
-surgery that involves neural tissue
-condition that cause nerves to become dysfunctional
sources of athletic injury pain
learned pain -learned, or conditioned, response --"pain memories" -\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ idiopathic pain -unknown origin --no identifiable pathology
placebo
- latin
- ___% receive relief
latin-I shall please mock intervention patient belief psychological effects 35% of postoperative, diabetes, or chronic headache patients receive relief from placebos
placebos
-why?
power of the mind believing something will work may increase effects -educate patients -be positive -set goals
pain relief types
direct
indirect
direct
get rid of the pain source
indirect
treating the pain but not the source
tools for relieving pain
immobilization therapeutic exercise counter-irritants thermotherapy electrotherapy cryotherapy psychological tools
