Axial Skeleton 2 Flashcards
what is the vertebral column composed of?
Composed of a series of bones called vertebrae
what lies in-between each pair of (non-fused) vertebrae?
intervertebral (IV) disc
what holds the vertebral column together?
host of ligaments
functions of the vertebral column:
Protect the spinal cord (vertebral canal)
Attachment point for muscles, the ribs, and the pelvic girdle
Support the head
the cervical region:
7 vertebrae – C1-C7
thoracic region:
12 vertebrae – T1-T12
lumbar region:
5 vertebrae – L1-L5
sacrum
5 fused vertebrae – S1-S5
coccyx
2-4 fused vertebrae – Co1-Co4
What are the distinguishing features of cervical vertebrae?
Cervical vertebrae always have transverse processes and may have a bifid spinous process, which means the spinous process has split into two.
What are the distinguishing features of thoracic vertebrae?
Thoracic vertebrae articulate with the ribs and have facets for articulation. They also have a downward-pointing spinous process and superior and inferior demi facets on their bodies, as well as facets on the transverse processes for articulating with the ribs.
What are the distinguishing features of lumbar vertebrae?
Lumbar vertebrae have wider bodies and square spinous processes, which are blockier in shape to support more weight.
convex anteriorly:
cervical and lumbar curve
convex posteriorly:
thoracic and sacral curve
purpose of normal vertebral curves:
Increase the strength of the vertebral column
Shock absorption
Help maintain balance in the upright posture
vertebral foramen:
Collectively, these form the vertebral canal, which contains the spinal cord
what makes up the anterior half of the vertebra?
the body
what does the vertebral arch form?
the posterior half of the vertebra and includes several processes extending from it.
The vertebral foramen:
encircled by the body and vertebral arch and contains the spinal cord.
vertebral canal:
The stacked vertebral foramina form the vertebral canal, which protects and contains the spinal cord.
extending posteriorly from the body:
the pedicles.
Where do the laminae meet, and what do they form?
The laminae meet in the midline at the back of the vertebral foramen, forming the posterior portion of the vertebral arch.
What structure extends posteriorly from the back of the vertebral arch?
A spinous process extends posteriorly from the back of the vertebral arch.
What structures extend laterally from the vertebral arch?
Two transverse processes extend laterally from the vertebral arch.
What structures extend superiorly and inferiorly from the vertebral arch, and what joints do they form?
Superiorly from the vertebral arch are two superior articular processes, and inferiorly are two inferior articular processes. The superior articular processes of one vertebra articulate with the inferior articular processes of the vertebra above, forming the zygapophyseal or facet joints.
What is the role of the intervertebral disc, and how many joints are there between each pair of vertebrae?
The intervertebral disc connects the bodies of adjacent vertebrae and acts as a joint. There are three joints between each pair of vertebrae: two zygapophyseal joints and one intervertebral disc joint.
What structures emerge from the intervertebral foramina, and how many are there between each adjacent pair of vertebrae?
Each pair of spinal nerves, arising from the spinal cord, emerge from the intervertebral foramina. There are two intervertebral foramina between each adjacent pair of vertebrae: one on the left and one on the right.
what are intervertebral discs composed of?
Annulus fibrosus – outer ring of fibrocartilage
Nucleus pulposus – inner elastic core
function of the intervertebral Discs
Function to absorb vertical forces on the vertebral column
what happens to an IV disc when compresses?
flattens - they lose water and shrink in height.
What can happen if there is acute or chronic trauma/strain on the intervertebral discs?
Damage to the annulus fibrosus may occur, leading to herniation of the nucleus pulposus through the annulus fibrosus into the vertebral foramen.
Where does the nucleus pulposus most commonly herniate?
The nucleus pulposus most commonly herniates posterolaterally.
cervical vertebra: size
small
cervical foramina:
one vertebral
two transverse