Vertebral Column Flashcards
the veryebral column is composed of
33 vertebrae:
7 cervical
12 thoracic
5 lumbar
5 sacral
4 coccygeal seperated from each other by intervertebral discs
structure of a typical vertebrae
1. vertebral body
2. vertebral arch composed of two pedicle and two lamina
3. vertebral foramen between body and arch transmits spinal cord
4. intervertebral foramens transmit the spinal nerves
5. seven processes (2 transverse, 2 superior articular, 2 inferior articular, 1 spine)
properties of a typical cervic vertebra
- the body is small and oval
- the foramen is large & triangular
- the transverse processes are short, bifid with a foramen (foramen transversarium) which transmit vertebral artery vein
- the spine is short and bifid
7th cervical vertebra (atypical) (vertebra prominens) its has the longest not bifid spinous process
what is the atlas
• its the 1st cervical veryebra
• its ring-shaped and has 2 lateral masses connected by an anterior arch and a posterior arch
-each lateral mass articulates above with an occipital condyle of the skull, and below with the superior articual process of axis vertebra
what is the axis
its the 2nd cervical veryebra and its characterized by the large tooth- like dens (odontoid process), which extends superiorly from the vertebral body
typical thoracic vertebra, lumbar vertebra, comparision between vertebrae and ligaments of intervertebral joints are read only
from slide 19-22 + slide 24 + slide 30
whats the sacrum
- the 5 sacral vertebrae join to form one mass known as the sacrum
- it is roughly triangular with a base above & apex below and has 4 anterior & 4 posterior sacral foramina
whats the coccyx
the coccygeal segments join to form one mass known as the coccyx
joints of the vertebral column
they articulate with each other by cartilaginous joints between their bodies and by synovial joints between their articular processes
function of the intervertertebral discs
- act as shock absorbers
- their elasticity allows the rigid vertebrae to move one on the other
-their elasticity is gradually lost with advancing age
(type: secondary cartilaginous)
structure of the joints of the vertebral column
- the upper and lower surfaces of the bodies of the vertebrae are covered by thin plates of hyaline cartilage
- between the plates of hyaline cartilage is an intervertebral disc of fibrocartilage
- each intervertebral disc consists of:
1. peripheral part, the anlous fibrous is composed of concentric layers of fibrocartilage
2. central part, the nucleus pulposus is an ovoid mass of gelatinous material contains amount of water, a small number of collagen fibers and a few cartilage cells
its normally under pressure and situated slightly nearer to the posterior than to the anterior margin of the disc
what effects does intervertebral disc herniation have
- leads to compression of spinal nerves and neurological manifestations
- sensory like numbess pain or sensory loss or motos as muscle weakness
what effects does intervertebral disc degeneration have
as effect of aging and disc degeneration thus limiting the ability of the disc to absorb shock
joints between vertebral arches (zygapophyseal joint) type and articular surfaces
type: plane synovial
articular surfaces: between the superior and inferior articular processes of adjacent vertebrae, the articular facets are covered with hyaline cartilage, and the joints arr surrounded by a capsular ligament
ligaments of the spine (vertebral arches?)
1. Supraspinous ligament: between the tips of adjacent spines
2. Interspinous ligament: connects adjacent spines
3. Intertranverse ligament: between adjacent transverse processes
4. ligamentum flavum: commects the lamomae of adjacent vertebrae
5. Ligamentum nuchae: in the cervical region, the supraspinous and interspinous ligamnets are greatly thickened to form the strong ligamentym nuchae
movement of the vertebral column
flexion: is movement forward
extension: is a backward movement
(both are extensive in cervical and lumbar regions, but restricted in the thoracic region)
lateral flexion: is the bending of the body to one or the other side
it is extensive in the cervical and lumbar regions but restricted in the thoracic region
rotation: is a twisting of the vertebral column, this is the least extensive in the lumbar region
circumduction is a combination of all these movements
atlanto-occipital joints articulation, type and movements
type: synovial ellipsoid joint, biaxial
articular surfaces: Occipital condyles above, and the superior articular surface of the atlas vertebra below
movements: extension, forward and lateral flexion
atlantoaxial joints
- the medial atlantoaxial joints
- the lateral atlantoaxial joints
the median atlantoaxial joint type and articulation
articular surface: between the odontoid process and the anterior arch of the atlas
type: pivot synovial (rotation)
the lateral atlantoaxial joint type and articulation
articular surface: inferior surface of articular surface of the atlas and the superior axial articular facets
type: plane synovial
curves of the vertebral column
- in the fetus, the vertebral column has one continuous anterior concavity
- after birth, when the child becomes able to raise his head the cervical part of the vertebral column becomes conves anteriorly (cervical lordosis)
- towards the end of the first year, when the child begins to stand upright, the lumbar part of the vertebral column becomes convex anteriorly (*lumbar lordosis)
abnormal curves of the vertebral column
1. kyphosis: is an increase in the sagittal curvature present in the thoracic part of the vertebral column
causes: by muscular weakness or by structural changes in the vertebral bodies or by intervertebral discs
2. lordosis: is an exaggeration in the sagittal curvature present in the lumbar region
3. scoliosis: is a lateral deviation of the vertebral column
its most commonly found in the thoracic region
