PHTY209 Lecture Notes - Lecture 14: Sunburn, Catecholamine, Secondary Somatosensory Cortex
Understanding pain
• Why study pain?
o The International Association for the Study of the Pain (IASP) brings together scientists,
clinicians, health-care providers, and policymakers to stimulate and support the study of
pain and translate that knowledge into improved pain relief worldwide
(https://www.iasp-pain.org/)
o According to IASP:
• The physiotherapist is an essential member of the pain-management team and
advocates for an individualised pain-management plan that integrates the
perspectives of the patients, social support systems, and team members
• Pain has a widespread prevalence; The right of people in pain to have access to
care
• Pain is one of the most common reasons people seek care from
physiotherapists/physical therapists
• All health care professionals require comprehensive pain education and know how
to apply that to different patients with varying pain types
• Pain can be acute and easily resolved or persist and become chronic or recurrent
• Pain can have an obvious traumatic commencement or start without a clear
initiating injury
• The pia theapeuti ojetie of phsiotheapists/phsial theapists okig
with people experiencing pain is to provide evidence-based person-centered care
that promotes health and well-eig aoss the lifespa, … iteetio
consistent with ICF.
1. Define and explain pain to others (patients, people, community, colleagues) as a complex,
multidimensional experience
o A upleasat seso ad eotioal epeiee assoiated with actual or potential
damage o desied i suh tes of daage. IA“P defiitio
o Sensory and Emotional means:
• Physical and psychological response
• Experience, emotion and culture all contribute
• Pain is always subjective, hence difficult to measure. alas eal - a number of
contextual factors contributing)
o Multidimensional nature of pain
• A number of contextual factors contribute to the experience of pain including:
▪ Biological
▪ Physical
▪ Psychological
▪ Occupational
▪ Social
▪ Cultural
▪ Environmental
• The nature of the relationship between tissue insult, injury and pain is variable.
o Three Dimensions of Pain
• Sensory-discriminative:
▪ Sensation of pain – location, quality (burning, dull, sharp), intensity and
duration.
• Motivational-affective:
▪ The unpleasantness of pain or how much the pain bothers the person.
• Cognitive-evaluative:
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▪ Puts pain in terms of past experiences and probability of outcomes.
2. Understand and describe the neurological pathways from the nociceptor to the cortex, and
the different pathways involved in the processing and modulating nociceptive information and
pain experience (peripheral, spinal and brain) including:
o Recall definitions from somatosensory lecture
• Somatosensation: sensory information from the skin and musculoskeletal systems
• Stimulus: something that can be sensed
• “eso “tiulatio: adeuate stiulus, a e piked up eepto
• Receptor: sensory receptors can detect and convert stimulus; located at distal end
of peripheral neurons
• Transmission: once stimulus converted to electrical activity in the peripheral
terminals of sensory fiber, action potentials conducted along axons and across
synapses to S1
• Modulatio: up egulatio ad do egulatio a odulate ifoatio
coming into the sensory system
• Processing: sensory information converted to a format the brain can use
• Perception: what is perceived by the brain e.g. nociception -> pain
• Body Representation/Body Schema: our understanding of our physical selves in
the world
• BIG PICTURE - Stimulus; Receptor; Neurons - 1st, 2nd and 3rd order ;
Somatosensory cortex; Response
o Recall Fibre Types
o Pathways
• Several ascending pathways transmit nociceptive information:
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find more resources at oneclass.com
• Recall the spinothalamic tract (neo)
• Recall the trigeminal tract
o Nociception versus pain
• The sensory experience of pain caused by a noxious stimulus is mediated by a
specialised high-threshold sensory system, the nociceptive system
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Social: the nature of the relationship between tissue insult, injury and pain is variable, three dimensions of pain. Somatosensation: sensory information from the skin and musculoskeletal systems. Large receptive fields (makes localisation hard) no peripheral specialisation. Initial activation of nociceptors will transmit signal (via action potential) from free nerve ending along dendrite, through neuron cell body (located in the dorsal root ganglion), along the axon and arrive at the dorsal horn of the spinal cord. Supraspinal structures: spinal cord mechanisms of modulation include, central sensitisation, gate control theory and modulation, supraspinal influences, first and second pain, classification of sensory afferent neurons, a a(cid:374)d c fi(cid:271)(cid:396)es. First pain, fast pain signals a threat rapid and accurate localisation: withdrawal from stimulus (cid:272)a(cid:396)(cid:396)ied (cid:271)(cid:455) a fi(cid:271)(cid:396)es. Second pain, slow pain: delayed onset (up to 1 s later) longer lasting, motivates behavioural responses to limit injury and optimise recovery carried by c fibres, case example.
