Class 3 - The Spinal Cord Flashcards
List the protective layers of the spinal cord from outermost to innermost.
vertebrae epidural space dura mater subdural space arachnoid mater subarachnoid space pia mater denticulate ligaments
The cervical enlargement is seen between…
C4-T1
The lumbar enlargement is seen between…
T9-T12
The conus medullaris ends at the level of…
L1-L2
What is the filum terminale?
extension of pia mater that fuses with the arachnoid and dura maters, then anchors the spinal cord to the coccyx
What is in the dorsal vs. ventral roots of the spinal nerve roots?
dorsal - sensory axons only
ventral - motor axons only
What is the cauda equina?
nerves that arise from the lumbar, sacral, and coccygeal regions of the spine move somewhat parallel to the spine downward before exiting the vertebral canal
The central canal is continuous with…
the fourth ventricle in the medulla
The ventral gray horns contain…
somatic motor cell bodies (nuclei)
The dorsal gray horns contain…
axons of sensory neurons + cell bodies of interneurons
Lateral gray horns are only present in…
the thoracic and upper lumbar segments of the spinal cord
What is contained in the lateral gray horns?
autonomic motor nuclei
Which white columns contain mostly motor tracts?
the anterior/ventral white columns
Which white columns contain only sensory tracts?
posterior/dorsal white columns
What is the conus medullaris?
terminating/tapering off of the spinal cord
The cauda equina is enclosed by… and surrounded by CSF in the ____ space
a bag-like structure of the dura and arachnoid mater
subarachnoid space
Where does a spinal tap draw CSF fluid from?
the subarachnoid space around the sac enclosing the cauda equina
Which meningeal layer is continuous with epineurium?
dura mater
What are the denticulate ligaments, and what are they for?
thickenings/extensions of the pia mater which suspend the spinal cord in the middle of its sheath to prevent sudden displacement
What is the gray commissure?
the crossbar of the “H” which the central canal pierces through
The posterior white funiculi can be divided into two tracts, which are:
gracile fasciculus
cuneate fasciculus
Direct motor pathways are also called _____ and are for ______ movements
pyramidal
voluntary
Indirect motor pathways are also called _____ and are for _____ movements
extrapyramidal
autonomic movements (such as maintenance of posture)
What are the 3 possible fates for information entering the spinal cord?
- head straight to the brain
- synapse with interneuron –> ascend to brain
- spinal reflex pathway
Where is the spinal cord the thickest?
lower cervical spine
Spinal nerves C1-C7 all exit the vertebral canal ____ their corresponding vertebrae
above
Spinal nerves T1-L5 all exit the vertebral canal ___ their corresponding vertebrae
below
What is the function of the meningeal branch of spinal nerve roots?
to re-enter the intervertebral foramen and supply the vertebrae, ligaments, blood vessels of spinal cord + meninges
The rami communicantes is a component of which division of the nervous system?
the ANS
Lateral gray horns are found in which regions of the spinal cord?
thoracic and upper lumbar
Which spinal nerve segments serve the upper and lower limbs?
the cervical and lumbar enlargements
Which spinal nerve does NOT have a corresponding dermatome?
C1
The phrenic nerve is made up of nerves from which spinal segments?
C3, C4, C5
What is contained in the lateral gray horns?
autonomic motor nuclei
What is the outermost covering of the spinal nerves?
epineurium
Which space in the spinal cord holds CSF?
the subarachnoid space (and central canal)
What is held in the epidural space?
fat + connective tissue
The dura mater forms a sac around the spinal cord from the level of the foramen magnum to the…
level of S2
Which of the following is found in the anterior white column of the spinal cord?
lateral corticospinal tract
lateral vestibulospinal tract
lateral reticulospinal tract
lateral vestibulospinal tract
Which is the only sensory tract in the anterior white column?
anterior spinothalamic tract (or at least, part of it)
Which of the following is found in the anterior white column of the spinal cord?
anterior spinocerebellar tract
anterior spinothalamic tract
posterior spinocerebellar tract
anterior spinothalamic tract
A spinal tap draws CSF fluid from where?
the subarachnoid space at the level of the cauda equina
Where is the spinal cord the thickest? And next thickest?
cervical spine, then lumbar spine
In which region of the spinal cord are the lateral grey horns mainly present?
thoracic (mainly) but also lumbar
The posterior white column contains…
only sensory tracts
The anterior white column contains…
mostly motor tracts, plus the anterior spinothalamic tract
