spinal column Flashcards
describe the role and function of the spinal/vertebral column (
- protects spinal cord and gives rise to spinal nerves
- maintains balance
- supports head trunk
- absorbs mechanical shock from weight bearing exercise
describe the basic structure of the vertebral column
- series of mobile, stacked bones (vertebrae)
- held together by ligaments and muscles
- separated from each other by intervertebral discs
what type of bones are the vertebrae?
irregular shape
Describe the different types of movement enabled by the spinal column
- (forward) flexion
- (backward) extension
- lateral flexion (side to side)
- rotation (twisting side to side)
- circumduction (circles with head)
Describe the difference in curvature of Adult vs Foetal vertebral column
Adult vertebral curves consist of 4 parts:
- cervical, lumbar (convex curves) & thoracic, sacral (concave)
Foetal vertebral column consists of just one curve in uterus
- secondary
when does a baby develop a secondary cervical curvature?
when they can hold their head up (around three months)
when does a child begin to develop adult-like vertebral curves?
as soon as they start weight bearing on legs do the curves start developing
Name the 4/5 regions of the spinal column (superior to inferior)
Cervical
Thoracic
Lumbar
Sacrum
- Coccyx
Describe the three main functions of intervertebral discs. Where are they found?
Found between the bodies of adjacent vertebrae
Function:
- strengthens joints
- permits movement
- absorbs vertical shock
describe the structure of an intervertebral disc
- outer rim of fibrocartilage
- central core: nucleus palposus
what has happened in the intervertebral disk when we talk about a “slipped” or “perforated disc”?
the central core, the nucleus palposus has perforated through the band of fibrocartilage.
where is the spinal cord located within the vertebral bone?
the vertebral foramen (cavity within the bone)
can spinal nerves come out from the dedicated foramina cavity?
yes
Describe the components of a typical vertebra (5)
- vertebral foramen (spinal cord’s cavity)
- articular facets (bits where bones articulate)
- vertebral body (bone structure, changes along the spinal column)
- transverse process*
- spinous process*
*Both sites for muscle attachment
How many vertebra make up the Cervical region of the spinal column?
7
Name and describe C1-C2 of the cervical region - why are they different to the rest?
These vertebra are shaped differently than the rest of the cervical vertebra due to their position and role.
C1: Atlas, seats the occipital bone of the skull
- no spinous process
C2: Axis, seats C1 and allows rotation
- distinguished by the dens (onto process) that extends upwards from the vertebral body and joins with the inner atlas
Describe the structural components of C3-C7 of the cervical region
- Round Foramen (spinal cord cavity)
- Articular facet: where bones articulate to
- bifid (two pronged) spinous process
How many vertebral bones make up the Thoracic region?
12
Describe the unique aspects and role of the Thoracic region
- mid thoracic vertebra: long, pronounced spinous process
- supports and articulates the ribs
- larger than cervical, supporting more weight
- vertebral foramen are round
What is the main unique feature of thoracic vertebrae?
Vertebral processes that articulate to the ribs and spine
Describe the features and role of the Lumbar region
- stronger than superior regions
- largest vertebra as they support most weight
big spinous process to attach muscles of the lower back - triangular vertebral foramen
How many bones in the Lumbar region?
5
Describe the structure of the Sacrum
5 vertebrae fused together to form a triangular shaped bone
To what does the sacrum articulate to? (superiorly)
the 5th lumbar vertebra
what does either side of the sacrum articulate to to form?
the ilium (pelvis), forming the sacro-iliac joint
where does the coccyx articulate to?
the inferior tip of the sacrum
what does the coccyx consist of?
4 vertebra fused together
which way do the superior articular processes of thoracic vertebrae face?
anteriorly
which way do the inferior processes of thoracic vertebrae face?
posteriorly
what do all thoracic vertebrae have located on the lateral sides of the body?
costal facets (rib facets)
where do the ribs attach?
to the superior and inferior costal facets on the lateral sides of thoracic vertebra
what are lumbar vertebrae characterised by?
- large thick body
- short spinous process
- posterior view of vertebrae looks like a moose
- triangular foramen (spinal cavity)
what is an intervertebral disc? describe its purpose
- fibrocartilanginous pad that fills the gap between adjacent vertebral bodies
- to provide padding between vertebrae during weight bearing
where are intervertebral discs thickest, and thinnest?
thickest in the lumbar region
thinnest in the cervical region
*this is because the lumbar region bears the most weight
describe the components of an intervertebral disc (outer layer and core)
- anulus fibrous (tough fibrous layer)
>forms a circle and is anchored to the adjacent vertebral bodies - nucleus pulposus
>softer gel like material
>water content that resists compression
>important for weight bearing
What changes within the Nucleus Pulposus as a person ages?
- water content of the gel like disc decreases
- thinning the disc and reducing flexibility and range of motion of the disc making bending more difficult
which ligament is only found in the cervical region of the vertebral column?
nuchal ligament
