Vertebral Column, Meninges, & Spinal Cord Flashcards
What is the superficial back muscle group called?
Axio-Appendicular
What is the intermediate back muscle group called?
Respiratory
What is the deep back muscle group called?
Intrinsic Back
What is the axial skeleton
bones of the cranium, vertebral column, sternum and ribs
What is the appendicular skeleton
pectoral girdle, upper extremity, pelvic girdle, lower extremity
Where does the vertebral column begin and end?
begins = foramen magnum
ends= tip of coccyx
75 cm in length (2x length of spinal cord)
How many vertebrae are in each section of the vertebral column?
Cervical = 7 Thoracic = 12 Lumbar = 5 Sacral = 5 (fused) Coccygeal = 3-5 fused (32-34 total)
What are the four curvatures of the spine?
Lordosis “concave” = cervical and lumbar
Kyphosis “convex” = thoracic and sacral
What is lateral curvature of the vertebral column called?
scoliosis
How does the intervertebral disc impact the intervertebral foramen in thoracic/lumbar vs cervical regions?
In thoracic/lumbar regions, the intervertebral disc makes up half of the intervertebral foramen (inferior portion)
In cervical vertebrae, the intervertebral disc spans the whole intervertebral foramen
Where do spinal nerves C1-C7 exit in C1-C7 vertebrae?
Spinal nerves in the cervical area exit the inferior portion of the intervertebral foramen above the corresponding cervical vertebrae.
Where does spinal nerve C8 exit the vertebral column?
The superior portion of the IV foramen above T1 vertebrae
Where do spinal nerves T1- L5 exit in T1-L5 vertebrae?
These spinal nerves exit in the superior portion of the IV foramen below the corresponding vertebrae
Where do spinal nerves S1-S4 pass through vertebral column?
They pass via the anterior/posterior sacral foramina
Where do spinal nerves S5 and Co1 pass through?
They pass via the sacral hiatus
What vertebral level does the spinal cord end?
L1-L2 (where it forms the conus medullaris)
What is the cauda equina?
The nerve roots below L2 descend in the vertebral canal (like a horse tail) and exit at the corresponding vertebral level
What three unique components are on the transverse processes of cervical vertebrae?
Posterior tubercle, Groove for spinal nerve, and Anterior tubercle
What movements do the transverse facet joints in cervical vertebrae allow?
Permit flexion and extension (some lateral flexion) NO rotation (only C1 & C2)
What two things are unique about C7 vertebrae
1) . The transverse foramen are a lot smaller because vertebral artery DOES NOT pass through, only vertebral vein
2) . Spinous process is the longest and not bifid
What vertebra is most commonly fractured?
T 12
What characteristic on C6 vertebra is so special?
The Carotid tubercle on the anterior surface of transverse process could compress carotid artery
What two parts of the thoracic vertebrae do the head of the ribs connect to?
there are two costal facets (superior and inferior) portions of adjacent vertebrae PLUS 1 on each transverse process where rib lays
What facet joints are the in thoracic region and what movement does it allow?
coronal facets
It permits rotation
What is important about the shape of the L5 vertebra?
The back is switching from lordosis to kyphosis orientation so L5 is wedge-shaped to accommodate for that lumbosacral angle
What direction are the lumbar facet joints and what movements do they allow?
sagittal
They allow for flexion/extension and Lateral flexion
What parts of the pelvis does the sacrum make up?
The sacrum males up the roof and posterior wall of the pelvis
What is the sacral promontory?
It is a landmark on the anterior side of the sacrum on the edge of the 1st sacral body that easily recognizes prominence of the roof of the pelvic cavity
What spinal nerves pass through the sacral canal and exit the sacral foramina? Which rami exits anteriorly vs posteriorly?
S1-S4; The ventral rami (motor) exit the anterior foramina and the dorsal rami (sensory exit the posterior foramina
What direction are the facet joints for cervical vertebrae?
Transverse
What are three unique features of the cervical vertebrae?
1) . Bifid spinous processes
2) . Widest vertebral body
3) . Uncinate processes (superior side of body is concave)
What is on C1 that holds the C2 dens in place?
Transverse ligament
Where can you palpate C1?
Between mastoid and angle of mandible
What are the two purposes of the dens?
C2
1) . axis of rotation for C1
2) . prevent displacement of C1 on C2
What is special about C2?
It is the strongest cervical vertebrae
What are two defining features of the thoracic vertebra?
Spinous processes are long and project downward
Costal facets
What are two defining features of lumbar vertebrae?
1) . Fat/massive body that’s kidney shaped
2) . blunt/thick spinous processes
What is the sacral canal?
It is the passageway for the cauda equina
What are the five landmarks on the dorsal surface of sacrum?
Lateral crest Intermediate crest Median crest Intermediate crest Lateral crest
What is the coccyx apex an attachment for?
the anococcygeal ligament
How much of the vertebral column height do the IV discs make up? %
25%
What portion of the intervertebral foramen does the IV disc make up?
The anterior, inferior portion
Describe the anulus fibrosis
Concentric fibrogelantinous rings
Thinner posteriorly
may be incomplete in cervical
Describe the nucleus pulposus
Fibrogelatinous (mostly water)
avascular
shock absorbing
What are the two longitudinal ligaments?
Anterior and posterior
Where does the anterior longitudinal ligament extend from and what movement does it limit?
It extends from sacrum to foramen magnum (covers anterior bodies and IV discs)
limits extension
Where does the posterior longitudinal ligament extend from and what movement does it limit?
Extends from sacrum to C2 (within vertebral canal; anterior to spinal cord)
hyperflexion
What is important about the posterior longitudinal ligament and a slipped disc?
It redirects posterior herniation of nucleus pulposus to spare the cauda equina (peripheral nerves get compressed though)
What does the filium terminale do?
It anchors the conus medullaris and meninges to coccyx
Name the order of three meninge layers and three spaces in order from inside to out
Pia mater Sub arachnoid space Arachnoid mater Subdural space Dura mater Epidural space
What layers of the vertebral column is the lumbar cistern and what is it?
L2 & S2
enlargement of subarachnoid space
What is unique about the sub dural space?
It is present when observing a cadaver because they isn’t CSF to compress it
How is Arachnoid mater attached to the pia mater?
Arachnoid trabeculae (spider webs)
What type of ligaments does the pia form?
Denticulate ligaments (20-22) to tether cord laterally to inner dural sac
What two ways can a herniation of nucleus pulposus occur?
1). flexion/hyperflexion
2). degeneration of anulus fibrosis
(nucleus pulposus protrudes usually posteriorly laterally through anulus fibrosis)
**get referred pain in corresponding dermatome because dorsal rami are pinches
What is steeles rule of thirds?
1/3 holds dens
1/3 holds spinal cord
1/3 holds empty space
Important for if dens fractures then it doesn’t cut off the spinal cord “silent fracture)
Explain herniation of disc & nerve compression in cervical vs thoracic/lumbar regions
Cervical disc occupy whole region of intervertebral foramen; C6-C7 herniation pinches C7 nerve because nerve protrudes superior to corresponding vertebrae in inferior border
Thoracic/lumbar regions- disc occupies only inferior portion; L4-L5 herniation; L4 is spared because protrudes in superior IV foramen space but L5 nerve descending down is compressed
What is the procedure to help with herniated nucleus pulposus?
Laminectomy
What space do you puncture for lumbar puncture?
subarachnoid space
What space do you puncture for epidural?
epidural space
What space do you puncture for spinal anesthesia
sub arachnoid
What type of paraplegia at C1-C3? How about C6-C8? How about T10-L3?
quadriplegia, ventilator dependent
paraplegia, upper limb paresis
variable lower limb function
What is spinal shock?
In terms of paralysis, cervical and thoracic transections might produce this which means you lose sympathetic innervation of vascular smooth muscle (cant regulate BP)
