Vertebrae Flashcards
What are the basic structure of a vertebrae?
anterior vertebral body and the posterior vertebral arch.
What is the weight baring portion of the vertebra?
vertebral body
Vertebral body
is lined by hyaline cartilage and is separated form adjacent vertebrae by the intervertebral discs
What forms the vertebral foramen?
together the vertebral arch and the vertebral body
What forms the vertebral or spinal canal?
in adjacent articulating vertebrae the vertebral foramina together
What is the vertebral or spinal canal’s purpose?
enclose and protect the spinal cord
pedicles
part of the vertebral arch connect the vertebral body to the transverse process
lamina
connect the transverse and spins processes
intervertebral discs and facet joints
adjacent vertebrae articulate with one another through
intervertebral foramen
created by adjacent vertebrae creating an opening through which the spinal nerve exits the vertebral/spinal canal.
What supports articulating vertebrae?
intervertebral discs and strong ligaments
What supports and strengthens vertebral bodies?
anterior and posterior longitudinal ligaments that run the length of the vertebral column.
Anterior longitudinal ligament
hyperextension of the spine
Posterior longitudinal ligament
weaker and limits hyper flexion of the spine
What supports the arches of the vertebrae further?
ligamentum flavum, interspinous ligament, supraspinous ligament, intertransverse ligament
ligamentum flavum
extends between the lamina of adjacent vertebrae
interspinous ligament
filling the space between the spinous process of adjacent vertebrae
supraspinous ligament
extending between the tips of the the spinous processes
inter transverse ligament
extending between the transverse processes
What are the intervertebral disc composed of?
fibrocartilaginous material
What is the outside portion of intervertebral disc called?
annulus fibrosus and consist of several layers of fibrous connective tissue
What is the central portion of intervertebral disc called?
nucleus pulposus a gel-like substance
What does the intervertebral disc do?
absorb the impact of pressure within the spine.
What happens to the intervertebral discs as one ages?
the nucleus pulposus lose moisture and spine becomes less able to absorb shock. the annulus fibrosus may also deteriorate with age and can begin to tear allowing the nucleus pulpous to bulge out of the disc
What is a herniated or slipped disc?
when the nucleus puplosus bulge out of the disc the bulging tends to occur laterally to one side compressing the spinal nerve on that side, those usually affection ones side of the body. occurs mainly in the cervical and lumbar regions.
what happens with a herniated disc in the C region?
compresses the nerve passing though the intervertebral foramen at the same level.
what happens with a herniated disc in the L region?
affects the next lower nerve
How does the spinal cord extend?
SC extends inferiorly within the vertebral/spinal canal surrounded by the meninges and CSF.
Where does the spinal cord end?
Approximately L2 by tapering into the conus medullaris
How is the spinal cord segmented?
31 spinal cord segments Cervical 8 Thoracic 12 Lumbar 5 Sacral 5 Coccygeal 1
Where do the spinal nerves leave the spinal cord and exit the vertebral column?
intervertebral foramina
What is the caudal equina
spinal nerves arise from the inferior end of the spinal cord (L2-S5) have to travel inferiorly to exit the vertebral column
How do each spinal nerve begin?
with a ventral/anterior (motor) root and a dorsal/posterior (sensory) root.
Where do the ventral and dorsal roots arise from?
the spinal cord and unite at the intervertebral foramina forming a single mixed spinal nerve that exits the vertebral column and divides into 2 rami (branches)
Dorsal/Posterior Ramus
motor and sensory nerve fibers to the synovial joints of the vertebral column, intrinsic muscles of the back, and skin of the back
Ventral/Anterior Ramus
motor and sensory nerve fibers to most of the remaining joints and muscles and skin of the body
What are spinal meninges?
3 membranes that surround the spinal cord. dura mater, arachnoid mater, and pia mater. create a space (subarachnoid space) that contains CSF
What does the spinal meninges and CSF do?
They support and protect the spinal cord
Where does the dura mater extend?
most external layer of the meninges externs from the foramen magnum to the middle of the sacrum.
What separates the dura from the walls of the vertebral canal?
epidural space
What does the epidural space contain?
fat, loose connective tissue, and internal vertebral venous plexus.
What happens to the dura mater when the spinal nerves exit the canal?
they pierce the dura mater which fuses with the outer connective tissue covering of the nerve.
Where does the dura continue?
below the conus medullar is into the sacral region of the vertebral canal and forms the lumbar cistern/dural sac/thecal sac that contains CSF and caudal equine.
What space is accessed during lumbar puncture and spinal anesthesia?
lumbar cistern/dural sac/ thecal sac
Where is the arachnoid mater located?
is a delicate membrane located between the dura mater and the innermost pia mater.
what separates the dura from the arachnoid and the arachnoid form the pia mater?
dura form the arachnoid subdural space and arachnoid from pia subarachnoid space.
Where space contains CSF
subarachnoid space
What is the pia mater
the innermost of the meninges, has a thin membrane that covers the spinal cord, nerve roots and their blood vessels
What is the film terminal
At the conus medullar is the spinal pia mater leaves the spinal cord, then attaches to the end of the vertebral canal anchoring the inferior end of the spinal cord.
