Anatomy of the spinal cord: Flashcards
the spinal cord starts and ends:
- starts: at foramen of magnum
- ends: at L1-L2 vertebrae (conus medularis)
the spinal canal surrounds:
the spinal cord to protect it
what do we find anteriorly to the vertebral body ? (as in arteries)
thoracic aorta with the posterior intercostal arteries
- the info from posterior horn:
- the info from the anterior horn:
- comes into
- comes out
- the 2 anterior sulcus = (which cords)
- the 2 posterior sulcus =
- delimit the motor cords
- the posterior sensory cords
the posterior and anterior cord arise from:
the vertebral artery = branch of the subclavian artery
the spinal arteries arise from:
the ascending cervical artery
on the thoracic level (T1): (what gives rise to what):
the thoracic aorta gives rise to the anterior and posterior spinal cord arteries
the lower spinal cord arteries = branches of:
the lumbar artery
the lumbar artery = branch of:
the abdominal aorta
the sacral artery = branch of:
the internal iliac artery
how many pairs of spinal nerves does the human have?
31
Artery of Adam Kewitz (supply?)
supplies the 2/3rds of the spinal cord
- if occlusion = can cause paraplegia (at the lumbar level)
Where do the meninges accompany the lateral roots to?
to the foramen into the spinal nerve sheath
in medullaris (under L2) (what do we find?) = within subarachnoid also
it’s the site where CSF can be accessed
what do we find between the pia matter and the arachnoid space ?
the subarachnoid space
the CSF flows through:
the central canal at the middle of the spinal cord and provides the brain and the spinal cord with nutrients
The CSF is produced in:
the brain’s ventricles
choronoid plexus
the cauda equina is within:
the subarachnoid space
above the dura we find (between dura and spinal canal):
the epidural space
the pia matter ends anteriorly and continues as:
the filum terminale (inferiorly)
between dura matter and arachnoid matter we find:
subdural space
in the intermediate furrow of the cervical cord we find:
- anteriorly: the bundle of GOLL
- a bit posteriorly: the bundle of BURDACH
the 3 horns and their functions:
- anterior = motor
- posterior = sensitive
- lateral = visceromotor anteriorly and viscerosensitive posteriorly
the spinal canal (vertebral column), (anatomy of each side):
- anteriorly: vertebral bodies (foramina) + reinforced at the walls through the intervertebral discs
- anteriorly + posteriorly = longitudinal ligaments
- posteriorly = laminae + yellow ligaments
- laterally = spinal nerves emerge (surrounded by articular processes + pedicles)
- from spinal cord + through intervertebral foramina = enter peripheral nervous system
the spinal nerves (where they’re formed from + where sensory and motor roots are located):
- formed by merging of 2 roots: sensory and motor
- sensory = from back of spinal cord
- motor = from front of spinal cord
function of CSF for brain:
acts as a hydraulic buffer, stabilising it with the vertebral canal
where is the brainstem located (junction):
at bulbomedullary junctions
the reflexes of spinal cord:
- most functions of the spinal cord = from brain, but some reflexes = in spinal cord independently = they’re either monosynaptic or polysynaptic
- the spinal cord neural pathway = within the white matter
enlargements in spinal cord (les trucs de vertebres)
. Cervical: origin of brachial plexus
. Lumbar: origin of lumbosacral plexus
the spinal curvatures (voir pic 2 google doc):
double S open with 3
curvatures (spinal curvatures)
. Cervical lordosis (between C1
and C7)
. Dorsal kyphosis (between C7
and T12)
. Lumbar lordosis (between T12
and L2)
where can we do lumbar puncture ?
between the spinous processes of the 3rd and 4th lumbar vertebrae or 4th and 5th lumbar vertebrae.
longitudinal grooves of the spinal cord:
- the deep anterior fissure,
- shallow posterior median sulcus,
- anterolateral and posterolateral sulci, and root filaments emerging on each side
the 3 furrows in anterior side of spinal cord:
➢ The anterior median fissure
➢ The right and left anterior
collateral sulcus (birth of the
ventral motor roots)
Delimit two front motor cords.
At the level of the anterior collateral furrows appear the anterior motor roots
(drawing notebook)
the 3 furrows in posterior side of spinal cord:
-There are 3 furrows on the
posterior surface of the SC:
-The posterior median
sulcus.
And then on both sides:
* The right and left
posterior collateral
sulcus.
-The two sulcus delimit the
posterior sensory cord.
-At the level of the
posterior collateral
furrows the posterior
sensory roots end with
the dorsal root ganglio
On either side of the ependyma
canal are:
- the anterior grey commissure
- the posterior grey commissure.
motor descending tract (what are his tracts/pathways):
- pyramidal beam (crossed and direct)
- lateral corticospinal tract
- ventral corticospinal
sensory ascending tracts:
- lateral spinothalamic tract (pain, temperature)
- ventral spinothalamic (light touch)
- lemniscal tract
- dorsal columns (deep touch, propioception, vibration)
spinal cord = (within)
vertebral canal
vertebral column: anatomical relationships:
- Formed by the vertebral foramina of the vertebral bodies
➢ anteriorly by : the vertebral bodies (reinforced at the walls through the intervertebral disks and the anterior and posterior longitudinal ligaments)
➢ posteriorly by the laminae (vertebral arches) and yellow ligaments
➢ Laterally by articular processes and pedicles - Laterally, the spinal nerves emerge from the spinal cord and pass through the intervertebral foramina, where they enter the peripheral nervous system.
diameter of spinal cord contains:
➢Spinal cord
➢Meninges
➢blood vessels
➢Spinal nerve roots and
surrounding fatty and connective tissues
The 3 meninges and in between: (look notebook for drawing):
- the pia mater
- The arachnoid mater
- The dura mater.
- These meninges delimit
spaces:
➢ Peri-dural space: between dura
mater and spinal canal, it is filled
with fat and venous plexus.
➢ Subdural space between
arachnoid and dura matter
➢ Subarachnoid space : between
the arachnoid and pia mater
filled by CSF
fixations of the spinal cord:
- The brainstem at the bulbomedullary
junction - The denticulate ligaments, extensions of the pia mater, anchor the spinal cord
laterally to the dura mater, helping to
maintain its position. - The filum terminale, a fibrous extension of the pia mater, extends from the conus medullaris and attaches to the coccyx, providing longitudinal stability.
- the cerebrospinal fluid (CSF) that fills the subarachnoid space cushions the spinal cord and acts as a hydraulic buffer, further stabilising it within the vertebral canal.
the meninges (what do they become?), (same ending as the muscles in abd wall!!)
accompany the roots laterally to the
foramen & gradually transform
into the spinal nerve sheath
spinal cord = supplied by branches of:
the vertebral and segmental arteries
the arterial axes: vertical:
- Anterior spinal axis: houses the anterior median furrow.
- Posterior spinal axis : two in number and house the posterior collateral groove
segmental axes:
Each medullary segment
receives its segmental
artery
- At the cervical level
(ascending cervical
artery and vertebral
arteries)
- At the dorsal level (5th
intercostal artery)
- At the lumbar level:
we have the ADAM –
KIEWICZ artery
anastomoses between 2 arteries + terminal arteries
Perimedullary arterial circle: Origin:
- Anastomosis between the radiculomedullary arteries and the anterior and posterior spinal axes
Termination:
- Short superficial arteries:
for white matter.
- Long deep arteries: for grey matter
Presence of a perimedullary venous
network which will drain into 3
main satellite veins to the spinal
axes: (photo google doc + slide 32)
Spinal veins = The epidural venous plexus = The venous network = peri-spinal veins
31 spinal segments giving:
➢ 8 pairs of cervical nerves 12 pairs of
thoracic nerves 5 pairs of lumbar
nerves,
➢ 5 pairs of sacral nerves
➢ 1 pair of coccygeal nerves
(Ponytail: lumbosacral nerves
spinal nerve posterior and back anterior branches:
- small posterior branch intended
for the sensory or motor innervation of the back - large anterior branch intended for the
innervation of the trunk and limbs
Spinal cord neural pathway found in:
within spinal cord’s white matter
- Ascending tracts convey information from:
- Descending tracts convey information from:
- periphery to the brain
- brain to the periphery
