Acute and Chronic Pain Flashcards
analgesia
absence of spontaneous report of pain or pain behaviors in response to stimulus normally expected to be painful
dysesthesia
and unpleasant abnormal sensation, whether spontaneous or evoked
hyperesthesia
increased sensitivity to stimulation, excluding special senses
hypoalgesia
diminished pain in response to a normally painful stimulus
neuropathic pain
pain arising as a direct consequence of a lesion or disease affecting the somatosensory system
nociceptor
a receptor preferentially sensitive to tissue or trauma or to a stimulus that would damage tissue if prolonged
nocioception
activation of sensory transduction in nerves by thermal, mechanical, or chemical energy impinging on specialized nerve endings
plasticity
nociceptive input leading to structural and functional changes that may cause altered perceptual processing and contribute to pain chronicity
What is the gate control theory?
an modulate pain at the spinal chord
Rubbing of large fibers will gate pain fibers at the spinal cord
highlights the importance of the spinal cord dorsal horn in modulating increasing pain signals, can be gated to eliminate pain signal from C-fibers
Descending pathways are also involved
three components: sensory, affective, evaluative
What is the neuromatrix theory?
individuals develop their own “neurosignature” as part of a neural netowrk which is influenced by a number of inputs (previous physical or psychological trauma), genetic susceptibility, cognitive and evaluative, that feed into a network of brain structures in creatin g”outputs” over time in one’s life manifesting as pain, one’s action program, and long term effects on the stress regulation or endocrine system
updated Gate Control Theory
transduction
detection of noxious or damaging stimuli
this signal is transduced into electrical activity by various types of nociceptors
thermal nociceptors detect extreme temperatures, chemical nociceptors detect noxious substances, and mechanical nociceptors detect high-intensity pressure
conduction
detection of noxious or damaging stimuli
resulting electrical signals are conducted via primary afferent nociceptive neurons to the dorsal horn of the spinal cord
transmission
synaptic transfer of input to neurons with specific laminae of DH
two ascending pathways - spinothalamic and spinoparabrachial tracts
spinothalamic tract relays through the thalamus to the somatosensory cortex and related areas
modulation
the sensation of pain and the response to pain are affected not only by pain transmission from affected neurons (via ascending pathways) but also by the brain’s response to that transmission (via the descending pathways)
inhibitory spinal interneurons and projections from the brainstem to the dorsal horn of the spinal cord modulate pain signaling by limiting the transfer of incoming snesory input to the brain
perception
the spinothalamic tract relays pain information through the thalamus to th esomatosensory cortex and associated areas, allowing for localization of pain, avoidance behavior, and cognitive processing of pain
affective response
the spinoparabrachial tract relays the pain stimulus to the parabrachial nucleus of the brainstem, continuing on to the ventral medial nucleus of the hippocampus and the central nucleus of the amyglada, brain regions involved in the affective response to pain
allodynia
a pain due to astimulus which does not normally provoke pain.
Temperature or physical stimuli can provoke allodynia, (which may feel like a burning sensation), and it often occurs after injury to a site.
hyperalgesia
an increased sensitivity to pain, which may be caused by damage to nociceptors or peripheral nerves
what is normally painful becomes much more painful
What are the outcomes of healing to injury with plasticity?
hyperalgesia and allodynia
will lead to chronic pain
What are the clinical symptoms of musculotendinous overload?
pain
instability
dysfunction
