Exam 1: Sensory Examination Flashcards
When a primary sensory modality isn’t working, what is the deficit referred to as?
Anesthesia or analgesia
What is decreased sensation and caused by nerve compression?
hypoesthesia
What is increased sensation caused by nerve irritation?
hyperesthesia
Explain the sensory pathway.
- neuron 1 is in the dorsal root either as lateral or media division info
- Neuron 1 enters spinal cord and synapses with neuron 2, which crosses midline and ascends in the a CNS tract carrying the impulse to the nucleus ventral posterolateralis/medialis of the thalamus
- Neuron 3 is at the thalamic nuceli and the thalamcocortical raditation travels to the somesthetic cortex on the post-central gyrus
Where does information from the lower part of the ascend?
medially within the cord
Where does information from hight parts of the body travel?
more laterally within the cord
What are other names for superficial sensations?
exetroceptive
Cutaneous sensations
What are the superficial sensations?
pain, temperature and light touch
Where do the receptors for exteroceptive sensations lie?
in the skin an mucus membranes
Where are superficials sensations carried in the cord?
anteriolateral district of the cord
What are the deep sensations?
pain, touch, and proprioception
Where are deep sensations carried?
posterior district of the spinal cord
Who based his observations on herpetic lesions and traumatic involvement of the spinal cord (dermatomes)?
Head
Who performed isolated posterior root sections and noted the remaining, or unaltered, sensibility after certain roots were cut?
Sherrington and forester
Who studied a large series of cases of herniated discs with the blocking of a single nerve root and modified the dermatome charts in the extremities?
keegan
What receptors are present in the skin and mucous membranes and ends of hair follicles and are sensitive to light and nondiscrimination touch?
tactile disc of merkel
What is thigmesthesia?
light touch or nondiscrimination touch
What pathway does light touch use?
Anterior lateral columns of the cord to the thalamus
What is deep touch or discriminating touch?
topesthesia
What receptors are on the hairless portion of the skin and are for deep and discriminating touch?
Corpuscles of meissner
What part of the cord is deep and discriminating touch carried?
posterior spinal cord district
What joint tissues are devoid of nociceptors?
- articular cartilage
- inner annulus and nucleus of IVD
- synovial membranes
The nociceptive system is active is the normal joint. T/F
False. It is inactive
What must happen to activate the nociceptive system?
a Noxious stimuli that may be mechanical, thermal or chemical
What substances have been shown to excite nociceptors?
K, hsitamine, serotonin, plasma kinins, prostaglandins, substance P
What fibers carry nociceptive impulses?
A delta (myelinated) C fibers (unmyelinated)
what word is used to designate areas insensitive to pain?
alganesthesia
analgesia
What term is used to designate areas of decreased sensitive to pain?
hypoalgesia
What term is used to designate areas of increased senstitivty to pain?
hyperalgesia
It is believed that temperature is superior for specialized localization of defect. T/F
True
For temperature examination, what should the cold stimuli be? hot stimuli?
Cold: 41-50 degrees F
Hot: 104-113 degrees F
