SCI Intro pt 1 Flashcards
central gray matter primarily consists of ____ and ____
nerve cell bodies, terminal axons
central gray matter also contains ____ and ____
neuroglia, blood vessels
where can you find the central canal, and what does it contain?
-Found in the Intermediate Zone
-Contains CSF
the intermediate zone houses ____ and other specialized nuclei
interneurons
where are the lateral horns found, and what do they contain?
-Contain cell bodies of autonomic preganglionic neurons
-T1 - L2 (sympathetic)
-S2 - S4 (parasympathetic)
does white matter increase or decrease as you move from caudal to cranial?
increase
volume of gray matter is highest in the ____ and ____ regions
cervical, lumbosacral
anterior spinal artery directly branches off the ____ artery and runs along the ventral surface of the SC
vertebral
anterior spinal artery supplies how much of the SC?
2/3
where does the posterior spinal artery come from?
right off the vertebral artery OR branches off PICA
what part of the SC does the posterior spinal artery supply?
posterior 1/3
what is the region of vulnerability?
-T4 - T8
-has dec perfusion compared to the rest of the SC
-most susceptible to infarct
functions of the sympathetic NS
Pupil dilation
Bronchodilation
Cardiac acceleration
Digestive inhibition
Piloerection
Systemic vasoconstriction
Stimulation of glucose release
functions of the parasympathetic NS
Pupil constriction
Bronchoconstriction
Cardiac deceleration
Digestion stimulation
Salivation
Lacrimation
Intestinal vasodilation
SCI at or above T6 → will see some kind of ____ dysfunction
ANS
what is the most common mechanism for lumbar SCI?
-Flexion
-Ex: MVA, struck from behind
what is the most common mechanism for cervical SCI?
-Flexion-rotation
-Results in torn ligaments and dislocation
what is an example of a mechanism for a compression injury?
-Landing with feet first
-Causes burst fx in vertebral bodies
hyperextension is almost exclusively seen in what part of the spine?
cervical
what are some non-traumatic causes of SCI?
-Disc prolapse
-Vascular insult
-Infection
what demographic is at highest risk for SCI?
males 20-29 and 70+ y/o
which cervical vertebrae are the most common to see involved in an SCI?
-C4 - C7 = most frequently involved areas of injury
-C5 and C7 = MOST common bc they have highest degree of mobility
do thoracic SCIs usually occur in the upper or lower T-spine?
lower
T/F: the T-spine is more likely to be injured from traumatic causes
False! The T-spine is LESS likely to be injured from traumatic causes d/t rib cage and higher stability as compared to cervical region
what is the most common site of T-spine injury?
thoracolumbar junction (T12-L1)
what is a common MOI for the T-spine?
flexion OR vertical compression
do lumbar SCIs usually occur in the upper or lower lx region?
upper bc the lower has thicker bodies and protection from the pelvis
are lumbar SCIs typically complete or incomplete?
incomplete d/t large vertebral canal and relatively good vascular supply
most lumbar SCIs occur where?
L1
what type of SCI occurs more frequently: complete or incomplete?
incomplete (BUT with paraplegia, complete v incomplete is about equal)
incidence of SCI based on region
cervical > thoracic > lumbar
what is the most frequent type of SCI?
incomplete tetraplegia
what is spinal shock?
-Temporary phenomenon w injuries T6 and above
-Cord in its entirety ceases to function below the lesion
-Loss of sympathetic tone
-Huge BP fluctuations: dangerously high → crash
how long does it usually take for spinal shock to resolve?
within 24h → several days of the injury
what is the first thing to return when spinal shock resolves?
sacral/anal reflexes
what is autonomic dysreflexia?
-Overactivity of the ANS w damage to T6 or above
-Body overreacts to an irritating stimulus below level of SCI
what is the most common trigger of autonomic dysreflexia?
full bladder (can be from catheter getting kinked)
symptoms of autonomic dysreflexia
-Pounding HA (due to high BP)
-Goosebumps
-Sweating above level of injury
-Bradycardia
-Check for flushing
what should you do if your pt starts experiencing autonomic dysreflexia?
-If pt is lying down, sit them up immediately
-If already in sitting, remain in sitting (DO NOT LIE THEM DOWN), perform pressure relief
-Check catheter, clothing, skin
Initiate emergency response if not resolved within 10 min
