Back Anatomy II Flashcards
what is the function of the spinal cord
acts as a highway that allows communication between the body and the brain
What is the spinal cord?
an extension of the brain stem
Where does the spinal cord stop and begin?
begins at the foramen magnum, stops between L1 and L2
_____ pairs of spinal nerves branch off of the spinal cord and pass through the intervertebral foramina
31
How many cervical spinal nerve pairs are there?
8 C1-8
How many pairs of thoracis spinal nerves are there?
12
how many pairs of lumbar spinal nerves are there?
5
how many pairs of sacral, and coccygeal spinal nerves are there?
5 sacral, one coccygeal
The cervical enlargement extends from ______ to______ and most ________ rami contribute to the _______ plexus which innervates the ________ limbs
C4 to T1, anterior, brachial, upper
the lumbosacral enlargement extends from _____ to _____ and most ______ rami contribute to the _______ and _______ plexuses which innervate the ______ limbs
L1-S3, anterior, lumbar, sacral, lower
Why does the spinal cord stop at the disc between L1 and L2?
because the vertebral canal grows much faster and to a larger extent than the spinal cord
The tapered lower end of the spinal cord is called the ______ ________
conus medullaris
What is the cauda equina?
bundle of spinal nerve roots arising from the lumbosacral plexus and running through the lumbar cistern
What is the lumbar cistern
subarachnoid space
The filum terminale consists mostly of _____ mater and extends from the ______ ________, passes through the ______ hiatus and is attached to the ________ coccyx.
pia, conus medullaris, sacral, posterior
what is the function of the filum terminale?
anchors the inferior end of the spinal cord to the posterior side of the coccyx
The anterior root sends what kind of information, where?
motor information from the spinal cord to skeletal muscles
the posterior root returns what kind of information and where?
returns sensory information from the peripheral sensory receptors to the spinal cord
The anterior and posterior root of each spinal segment combines to form a specific ______ nerve that exits through the ___________ foramen
spinal, intervertebral
Cell bodies of motor neurons are located in the ________ horns of the ________ matter
anterior, gray
cell bodies of the sensory neurons are located in the _________ ganglia outside of the _____________
spinal, spinal cord
anterior rami innervate what?
muscles, joints, skin of limbs, and anterior trunk
posterior rami innervate what?
zygopophyseal joints, muscles of back, skin of back
What spinal meninges cover the spinal cord?
pia mater, arachnoid mater, dura mater
__________ and __________ fluid surround, support, and ______ spinal cord and ________ nerve roots including the cauda equina
meninges, cerebrospinal, protect, spinal
how is the spinal dura mater separated from the vertebrae
by the extradural space that is occupied by adipose tissue and the internal vertebral venous plexus
spinal dura mater forms the _______ ______ sac
spinal dural
What is the spinal dural sac?
an elongated tube within the vertebral canal that runs from the margin of the foramen magnum to the coccyx where it is anchored via the filum terminale
what is the internum
filum inside of dural sac
what is the externum
pia enveloped in dura outside of sural sac, anchored to coccyx
as the spinal nerve roots extend into the intervertebral foramen, they are surrounded by _________________ which are continuous distally with the ___________ of the spinal nerve
dural root sheaths, epineurium
________________ mater lines the _______ sac and ___________ sheaths
spinal arachnoid, dural, dural root
What does the spinal arachnoid mater enclose?
cerebrospinal fluid-filled subarachnoid space containing spinal cord, spinal roots, and spinal ganglia
the subarachnoid space housing the cauda equina is the _________ _________
lumbar cistern
___________ __________ span the subarachnoid space and attach to the spinal ______ mater
arachnoid trabeculae, pia
What does the spinal pia mater envelop
spinal cord, spinal nerve roots, and spinal arteries
The spinal _______ mater continues as the filum terminale inferior to the conus medullaris
pia
What three longitudinal arteries supply the spinal cord?
one anterior spinal artery, and two posterior spinal arteries
spinal arteries extend from ________ _______ to the __________ medullaris
medulla oblongata, conus
Where do the spinal branches from cervical arteries and segmental arteries enter to supply the spinal cord?
intervertebral foramina
spinal branches from cervical arteries and segmental arteries enter some intervertebral foramina and divide into _______ and _________ segmental arteries to __________ supply of the spinal cord and anastomose with __________ spinal arteries
anterior and posterior
reinforce
longitudinal
_____________ and _________ radicular arteries supply spinal nerve roots and coverings
anterior and posterior
_____ anterior longitudinal veins and _____ posterior longitudinal veins drain the spinal cord
3, 3
____ anterior longitudinal artery and _______ posterior longitudinal arteries supply the spinal cord
1, 2
What are the superficial extrinsic muscles, what is their function?
trapezius, latissimus dorsi, levator scapulae, rhomboid
connect upper limbs to trunk
What are the intermediate extrinsic muscles, what is their function?
serratus posterior superior and serratus posterior inferior
respiratory muscles
What is the function of the intrinsic back muscles?
movement of vertebral column
What are the intrinsic back muscles innervated by?
posterior rami of spinal nerves
where do the intrinsic back muscles extend from?
pelvis to cranium
the fascia associated with thoracic and lumbar regions constitute the ____________ fascia
thoracolumbar
What are the superficial intrinsic muscles?
splenius cervicis and splenius capitis
What are the intermediate intrinsic back muscles?
iliocostalis (lumborum, cervicis, thoracis)
longissimus (thoracis, cervicis, capitis)
spinalis (thoracis, cervicis, capitis)
What are the deep intrinsic muscles?
semispinalis (cervicis, thoracis, capitis)
multifidus
rotatores (longus, brevis)
where do the deep intrinsic muscles originate from? insert on?
transverse processes and insert on superiorly located spinal processes
What are the additional deep intrinsic muscles between adjacent vertebrae?
intertransversarius, interspinales, levatores costarum
What are the suboccipital muscles?
rectus capitis posterior (major and minor)
obliqus capitus (superior and inferior)
What muscles are part of the sub occipital triangle?
superomedial: rectus capitus posterior major
superolateral: obliquus capitis superior
inferolateral: obliquus capitis inferior
The suboccipital triangle contains the _________ artery and the _________ nerve
vertebral, suboccipital
