Back pain Flashcards
What receptors detect pain and which sensory tract takes APs to the somatosensory cortex?
- Nociceptors (found on the membranes of high threshold neurones)
- Spinothalamic tract
What does ‘contralateral arrangement’ refer to?
How the left side of the brain gets information from the right side and vice versa
What is affective neuroscience?
It describes how different regions of the brain, when stimulated, can initiate a physiological response.
What are the 3 different type of stimuli that nociceptors can receive?
- mechanical (pressure)
- thermal
- chemical (reacts to cytokines at sites of inflammation)
What immediately happens to the nociceptor when it detects one of the stimuli?
The nociceptors undergo a conformational change which allows ions to enter, thus creating an AP.
How are the 2 paths of the spinothalamic tract different?
- Fast path that detects sharp pain (neospinothalamic)
- Slow path that detects dull pain (paleospinothalamic tract)
What type of fibres are found in the fast path?
alpha fibres
What type of fibres are found in the slow path?
c fibres
Describe the path of the general spinothalamic tract and where the neurones synapse
Nociceptors -> Dorsal horn -> decussation of neurones (contralateral movement) -> thalamus -> somatosensory centre
Which of these tracts also passes through the reticular formation, before going to the thalamus?
The slow path that carries signals for dull pain
What are some of the causes of lower back pain (lumbago)?
Issues with the…
- lumbar muscles + vertebrae
- spinal cord/ nerve roots
- aorta
- kidneys
- pancreas
What is referred pain?
- There are afferent nerves (that can detect pain) running from the viscera to the spinal cord/brain.
- However, these visceral afferents converge (convergence theory) with somatic afferents on their way to the CNS.
- This means that the brain misinterprets the pain signals from the viscera as pain signals coming from a muscle/skin (e.g. pain from the heart could be received as though it were coming from the skin/muscle)
What is the convergent theory?
Afferent signals from the viscera converge with the somatosensory system.
What is mechanical back pain?
- Where the source of the back pain is the vertebrae/soft tissues.
- There shouldn’t be any neurological features (i.e. parasthesia)
What is radiculopathy?
- Unilateral pain produced by the pinching of a nerve root in the spinal column.