Osteology of the Vertebral Column

Question 1

What are the 3 main functions of the vert column?

Answer 1

1. Main Axial Support for body
2. Protection
3. Flexibility

Question 2

How does the vert column provide main axial support for body?

Answer 2

• provides attachments for:
• skull
• thorax (articulates with ribs)
• pelvic girdle

Question 3

How does the vert column provide protection?

Answer 3

• spinal cord sits within vert foramen

- openings between adj vert for passage of spinal nerves

Question 4

How does the vert column provide flexibility?

Answer 4

• for trunk movements e.g. twisting, bending + carrying loads

Question 5

What is the spine composed of and why is its arrangement an adv?

Answer 5

• series of bony segments connected by discs + lig.s linked by synovial + secondary cartilaginous joints
• only small displacements of multiple linkages is necessary for a large overall motion rather than a few highly mobile articulations which would be less stable and flexible.

Question 6

What helps the spinal cord with movement?

Answer 6

• muscles

Question 7

Why does vert column have curves?

Answer 7

• allows more stability + flexibility

Question 8

What type of curve is the primary curve in the foetus and secondary curves in adult?

Answer 8

• primary curve - kyphotic

- secondary curves - lordotic

Question 9

What are the secondary curves for in the adult and how do they change?

Answer 9

• cervical: holding head up
• lumbar: walking
• due to posture + weakening of muscles that support them with age

Question 10

Name the parts of typical vert

Answer 10

• spinous process
• lamina
• pedicle
• vert foramen
• sup. + inf articular facets
• transverse process
• inf. + sup. notch
• body
• post. arch

Question 11

Where are synovial joints located in a typical vert?

Answer 11

• sup. + inf. articular facets

- post. arch

Question 12

What is function of inf. + sup. notch?

Answer 12

• where spinal nerves come through when they form a foramen

Question 13

How is the vert canal formed and what is its function?

Answer 13

• when put vert on top of each other

- where spinal cord, meninges + vessels come through

Question 14

What is function of vert body?

Answer 14

• supporting longitudinal loads

- takes up to 75% of forces going through vert

Question 15

What is the int. structure of the vert body and why is it like that?

Answer 15

• outer shell of cortical bone
• trabeculated internal structure horizontal + vertical - organised to resist stress and therefore add resilience to the structure
  + prevent compression from the side
• channels between the trabeculae are filled with blood which assists in absorbing the load.

Question 16

What are the functions of the lamina?

Answer 16

• protects contents of vert column
• Transmission of force from the articular processes to the body.
• takes 25% of forces going through vert

Question 17

Where is the lamina thickest and why?

Answer 17

between the superior and inferior facets and this also helps to withstand bending forces.

Question 18

What happens during osteoporosis?

Answer 18

• trabeculae gets thinner

- more force goes through lamina

Question 19

What is the structure + function of articular process?

Answer 19

• Paired superior and inferior processes bearing synovial joints.
• permit a limited amount of movement and, as the orientation of the joints changes throughout the column, the range of movement in each region varies.

Question 20

How do the shape of art facets differ in diff vert?

Answer 20

• cervical:
• flat
• vertically orientated (allows you to pivot head)
• thoracic:
• flat + vert joints - restricts bending but can get rotation
• lumbar:
• curvatures which limit rotation

Question 21

What are pedicles and what is their function?

Answer 21

• The connection between the posterior elements and the body of the vertebra.
• take forces at the joint + from muscle attached to transverse + spinous processes + transmit it onto body - therefore helping to resist unwanted movements and these stout pillars resist bending in any direction.
• The bodies are designed for weight bearing and therefore cannot resist twisting or sliding forces.

Question 22

What are the functions of the spinous and transverse processes?

Answer 22

provide areas for muscle attachment

Question 23

Name the 5 regions of the vert column and how many vert they have

Answer 23

Cervical - 7
Thoracic - 12
Lumbar - 5
Sacrum - 5
Coccyx - 2-4

Question 24

What are the features of cervical vertebrae?

Answer 24

• 2 foramina in transverse process for vert artery to supply post. aspect of brain + artery behind
• facets become more vert as go down which helps stability
• large foramen to allow entry of brachial plexus
• bifida in spinous process (C3-C6)
• uncovert joints in CS-C7 give movement and stability

Question 25

What is function of neurocentral articulation of cervical vert?

Answer 25

can provide another area of attachment in younger people

Question 26

What is function of ant. + post. tubercle of cervical vert?

Answer 26

for muscle attachment

Question 27

What is unique about C1 + C2?

Answer 27

- no body, art facet instead or spine - C1 has facet for dens which fits into C2 - articulates with occipital condyles - C2 has dens which allows pivot movement

Question 28

What is unique about C7?

Answer 28

- Long spinous sprocess = vert prominens | - no bifid

Question 29

What is sig about down pos of C2?

Answer 29

- restricted movement between C2 + C3 compared to C1

Question 30

What is the transverse lig. and its' function?

Answer 30

- attaches to lat. mass/tubercles across C1 | - ensures integrity of joint - prevents dens slipping back into spinal cord

Question 31

What is found between the occipital condyles and lat. mass of C1?

Answer 31

- V. strong synovial joint with strong capsules

Question 32

Where is the weight of the head transmitted?

Answer 32

- through occipital condyles to lat. mass of atlas | - all forces go through synovial joint and then weight transmitted to to bodies of cervical vert

Question 33

Where is location and what is function of art on thoracic vert?

Answer 33

- art on TP + 2 on body on both sides | - where ribs art

Question 34

What happens to art of thoracic vert from T10?

Answer 34

- shifts to middle of body

Question 35

How does the shape of thoracic vert change?

Answer 35

- cup shaped in upper (affects movements of ribs during resp) + flat shaped in lower - 1 + 2 backward facing - 3 + 4 downward facing - 5 to 8 has downward kissing spines and so not much movement - 11 + 12 backward facing

Question 36

Where do ribs art?

Answer 36

- through demi facets (1/2 joints)

Question 37

Describe the shape of lumbar vert

Answer 37

- L1 + L1 oval shaped and more rounded | - gets more triangular as you get lower

Question 38

Where does spinal cord end what changes?

Answer 38

- between L1 + L2 | - then you get horse's tail where spinal nerves exit and why shape changes

Question 39

What is unique about lumbar vert?

Answer 39

- no transverse foramina | - no rib art

Question 40

What does sacrum art with?

Answer 40

hip bone

Question 41

What is function of ant. pelvic sacral foramina?

Answer 41

nerves come here to supply lower limb

Question 42

What is function of interosseous sacroiliac lig.?

Answer 42

keeps sacrum in place

Question 43

What type of joint is sacroiliac joint and what is its function?

Answer 43

- synovial but little movement as its meant to be stress relief joint - prevents vert column slipping out of the pelvis