SCI Flashcards
33 vertebrae, how many in each section
7 Cervical
12 Thoracic
5 Lumbar
5 Sacrum (fused)
4 Coccyx (fused)
31 pairs of spinal nerves, how many in each section
8 Cervical (C1-C8)
12 Thoracic (T1-T12)
5 Lumbar (L1-L5)
5 Sacral (S1-S5)
1 Coccygeal
what makes up the spinal cord
33 vertebrae
31 pairs of spinal nerves
conus medullaris
cauda equina
dorsal horn
sensory
ascending neurons
ventral horn
motor
synapses with peripheral nerve
lateral horn
ANS
specifically fight or flight
is there more white or gray matter as you move caudal to cranial
WHITE
is there more white or gray matter as you move cranial to caudal
GRAY
dorsal column– medial lemniscus
(Conscious) proprioception, vibration, light and discriminative touch
Second order neurons cross in caudal medulla in internal arcuate fibers
anterolateral pathways
Pain, temperature, crude touch
Second order neurons cross at level of spinal cord through anterior commissure
spinocerebellar pathways
Unconscious proprioception from trunk and limbs
Ascends ipsi and contralaterally
Terminates in ipsilateral cerebellum
lateral corticospinal tract
function and where it crosses
Function: Volitional movement of contralateral limbs
Cross at the pyramidal decussation and descend contralaterally
anterior corticospinal tract
function
Function: Control of bilateral axial and girdle muscles
Descend ipsilaterally until level of spinal cord, at which point splits into bilateral innervation
rubrospinal tract
originates, crosses, and function
Originates in Red Nucleus, crosses in midbrain, and descends contralaterally
Assists LCST with descending drive for movement of contralateral limbs (flexors)
vestibulospinal tracts
medial and lateral
Medial VST: Originates in rostral medulla, descending bilaterally to cervical region to coantrol positioning of head and neck
Lateral VST: Originates in pons, descends ipsilaterally down spinal cord to aide in truncal control and balance
reticulospinal tract
originates and function
Originates in both pontine and medullar RF and descends ipsilaterally
Aids in posture and gait-related movements
tectospinal tract
originates, crosses, and function
Originates in superior colliculus, crosses in midbrain and descends contralaterally to upper cervical cord
Assists with coordination of head and eye movements
sympathetic nervous system
Fight or Flight
Pupil dilation
Bronchodilation
Cardiac acceleration
Digestive Inhibition
Piloerection
Systemic vasoconstriction
parasympathetic nervous system
Rest and Digest
Pupil constriction
Bronchoconstriction
Cardiac deceleration
Digestion stimulation
traumatic SCI MOI
MVA, GSW, jumps and falls, diving
Flexion (likely from a car crash)
Flexion + rotation
Extension + rotation
Vertical compression (landing feet first or diving)
Penetration
Hyperextension (falls; more common in c-spine)
non-traumatic SCI MOI
Disc prolapse, vascular insult, infections
Often have a worse prognosis
traumatic cervical spine injury
most common at
C4 - C7 most frequently involved areas of injury
C5 and C7 most common
traumatic cervical spine injury
most common MOI and other
Flexion + rotation
Vertical loading
Extension + rotation
Lateral flexion
Hyperextension
traumatic thoracic injury
most common site
T12-L1 junction
traumatic thoracic injury
most common MOI
Flexion or vertical compression
why are you less likely to be injured from traumatic thoracic injuries
Rib cage and higher stability as compared to cervical region
traumatic lumbar SCI MOI
flexion
traumatic lumbar SCI
most common location
L1
tetraplegic
Injury to the cervical spinal cord (C1-C8)
Involvement of all 4 extremities and trunk
paraplegic
Injury to thoracic or lumbar regions of spinal cord (T1 down)
Involves BLEs and trunk (chest down)
complete SCI
Absence of sensory and motor function below lesion level
More severe presentation of SCI – worse prognosis
Can have Zones of Partial Presentation (ZPP)
zones of partial presentation
Dermatomes and myotomes caudal to the sensory and motor levels that remain partially innervated
Movement rarely has functional importance
ex: can randomly flex ankle (trickling of ascending/descending capabilities)
incomplete SCI
Involves partial preservation of sensory and motor functions below the lesion level
Better prognosis than complete SCI due to preserved axon function
Incomplete SCIs occur more frequently than complete
what determines the degree of SCI
ASIA exam
most common sites of SCI injury
Cervical (C5 and C7) and thoracolumbar junctures (T12-L1)
most frequent type of SCI
incomplete tetraplegia