Spinal Cord Morphology and Lesions - 4/21 Stephens Flashcards
What structure may be compromised secondary to Thoracolumbar fracture or surgical repair of AAA?
Major supply to what?
Anterior artery of Adamkiewicz
Inferior 2/3 of the spinal cord
Which areas of the spinal cord are most vulnerable to ischemic necrosis of the spinal cord?
C2-3, T1-4, L1
Disruption of blood flow to what results in central cord syndrome?
Anterior spinal artery
What arteries supply the peripheral margins of the cord?
Posterior spinal arteries (2)
Radicular arteries
Gamma motor neurons are directly influenced by what tracts?
Output from the gamma motor neuron innervates what?
RF (reticulospinal)
Rubrospinal
Corticospinal
Intrafusal muscle fibers
Alpha and gamma neurons are what?
LMN
Location of SG?
Fx?
Sends fibers to?
Posterolateral tip of dorsal horn at all spinal levels
Pain/temp
LSTT
Location of NP?
Fx?
Sends fibers to?
Mid-portion of dorsal horn
Pain/temp
FP
Location of Nucleus Dorsalis?
Fx?
Sends fibers to?
Dorsal horn C8-L2
Unconscious proprio pathway
DSCT
Location of VAN?
Fx?
Sends fibers to?
T1-L2 and S2,3,4
Visceral sensory integration and reflex center
Intermediolateral gray, ventral horn, hypothalamus via RF
Location of IG?
Fx?
Sends fibers to?
Between dorsal and ventral horns at all spinal levels
Sensorimotor integration center
Ventral horn
The Medial Motor Cell Column is located where?
Innervates what?
Medial parts of ventral horn, all levels
Axial musculature
The Lateral Motor Cell Column is located where?
Innervates what?
Lateral part of ventral horn in the regions of the cervical and lumbosacral enlargements
Muscles of the extremities
Phrenic Nucleus is located where?
Innervates what?
C3-5, subdivision of the MMCC
Respiratory diaphragm
Spinal Accessory Nucleus is located where?
Innervates what?
C1-6, continuous with the nucleus Ambiguus in the medulla
SCM, traps
Intermediolateral Nucleus is located where?
Innervates what?
Lateral horn T1-L2
PRE-gang Symp fibers to visceral structures
SAN Nucleus is located where?
Innervates what?
Lateral horn S2-4
PRE-gang PS fibers to bowel and bladder
Sensory Dermatome spinal cord segment:
little finger, elbow?
Nipple?
Inguinal region?
T1
T4
L1
Sensory Dermatome spinal cord segment:
Thumb
Big Toe
Little toe
Perianal region
C5
L5
S1
S5
Motor Dermatome Reflexes spinal cord segment:
Brachialis
Triceps
Muscle of the hand
Gastroc m.
C6-7
C6-8
C8-T1
L5-S2
Motor Dermatome Reflexes spinal cord segment:
Quadriceps Femoris
Scapular
Abdominal
L2-4
C5-T1
T8-12
Motor Dermatome Reflexes spinal cord segment:
Epigastric
Cremasteric
Superficial Anal
T7-9
L1-2
S4-Co1
What important structure is located at the level of L1?
Conus medullaris
Spinal Cord Injury C1-4 results in what?
Disruption of phrenic nucleus and respiratory depression or arrest
Spinal cord injury above T1 results in what?
Horner’s syndrome if lesions to the reticulospinal fibers descending to the intermediolateral cell column at T1
Spinal cord injury above T2 results in what?
Sweating and vasomotor disturbances of the body
Rocking horse type of respiration is due to what injury?
C5-T6
Incontinence is due to a lesion where?
Results in what?
S3-5
Flaccid anal sphincter tone w/bowel incontinence
Lesions above where result in reflex bladder?
S2
Brown-Sequard Syndrome results from what?
Unilateral transverse lesion or hemisection of the spinal cord due to a knife or bullet wound, or to a meningioma
What characterizes Brown-Sequard Syndrome?
Ipsilateral loss of proprioception and vibratory sensations from the body below level of lesion - bc of post column
Ipsilateral spastic paralysis below lesion bc destruction of descending motor tracts
Contralateral loss of pain/temp from the body 2 segments below lesion due to destruction of LSTT
Macrocytic anemia causes what?
How can Macrocytic anemia result?
Degeneration of the posterior columns and pyramidal tracts and polyneuropathy
Atrophy of mucosal lining w/out intrinsic factor, therefore no absorption of vitamin B12
Signs of Subacute combined degeneration?
Numbness and tingling in fingers and toes (glove and stocking)
Bilateral loss of prop/vibratory sensation
UMN signs - Babinski, hyperreflexia, spastic paralysis
