Lecture 8: Vertebral Column Part 2

Question 0

Label views of sacrum and coccyx and read through commentary on slides 7,8 and 9

Answer 0

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Question 1

Label the diagram of the lumbar vertebrae on slides2, 3, 4, 5 and 6 and know its features. Also read through commentary word in the PowerPoint form of lecture on these slides

Answer 1

• n=5 vertebrae;
• Large kidney-shaped body for weight-bearing;
• Mid-sized triangular vertebral foramen;
• Facets are face medial or lateral direction permitting good flexion and extension;
• Spinous processes are short.

Question 2

Name all of the joints of the vertebral column

Answer 2

Joints of the vertebral column
•Intervertebral joints (joints between vertebral bodies)
•Zygapophyseal joints (joints between vertebral arches)
•Craniovertebral (atlanto-occipital & atlanto-axial joints)
•Costovertebral joints (articulations with ribs)
•Sacroiliac joints

Question 3

Tell me about the intervertebral joints?

Answer 3

• Joints between the adjacent vertebral bodies.
• Weight-bearing joints.
• Shock-absorbers due to IV discs.
• Stabilised by anterior (strongest) and posterior longitudinal ligaments.

Question 4

Tell me about the intervertebral discs
Slide 12
And their function?

Answer 4

From C2 to sacrum.
Anulus fibrous = fibrocartilage
Nucleus pulposus = gelatinous remnant (collagen, hydrated proteoglycans) of embryonic notochord
•IV discs thickest in lumbar region;
•Secured by anterior and posterior longitudinal ligaments.
-account for 20-25% of length of vertebral colum
Function: shock-absorbers, permit movement between adjacent vertebrae.

Question 5

Tell me about the ligaments and their function of the spine?
Slide 13 and 14 and 16
-attached to vertebral bodies and I.V discs?
-attaches mainly to I.V discs and less to vertebral bodies
-connect spinous tips? (C7- sacrum)
-connects spinous tops of cervical vertebral vertebrae to external occipital protuberance?
-connects transverse processes and are week?
-connects adjacent laminae of vertebrae?
-connects spines and are weak

Answer 5

Anterior longitudinal ligament is strong and prevents hyperextension of spine (only ligament that limits extension!)
➡Attached to vertebral bodies AND I.V. discs.

Posterior longitudinal ligament is weaker and prevents hyperflexion of spine.
➡ Attached mainly to I.V. discs and less to vertebral bodies.

Supraspinous ligaments connect spinous tips (C7 to sacrum) and are stronger and limit flexion.

Ligamentum nuchae connects spinous tips of cervical vertebrae to external occipital protuberance (i.e. superior continuation of supraspinous ligament!)

Intertransverse ligaments connect transverse processes and are weak

Ligamenta flava connects adjacent laminae of vertebrae.

Ligamenta flava limits flexion and are more elastic than other ligaments.

Interspinous ligaments connect spines and are weak.

Question 6

Tell me about the costovertebral joints?

Slide 17

Answer 6

Tranverse costal facets on the transverse processes for articulation with tubercle of ribs.

Superior and inferior costal facets (mostly small demifacets) on posterolateral margins of vertebral body for articulation with head of rib.

Question 7

Zygapophyseal “facet” joints

• type of joint?
• occurs between?
• allow for what movement
• which is our most mobile joint
• which segment allows most flexion
• what sensory nerves supply the synovial lining of the capsules surrounding these facet joints?

Answer 7

• Synovial plane joints.
• Occur between the superior and inferior arcticular processes (facets) of adjacent vertebrae.
• Allow for some gliding/sliding movement.
• C5-C6 is most mobile joint.
• L4-L5 permits most flexion.
• Sensory nerve fibres derived from dorsal rami of spinal nerves supply the synovial linings of the capsules surrounding these facet joints => 15 % of back pain caused by changes in these joints.

Question 8

Atlanto-occipital joints

Answer 8

Atlanto-occipital joints
Biaxial condyloid synovial joints
Allows flexion and extension and lateral flexion
Movement of the joint is limited by the anterior and posterior atlanto-occipital membranes
Slide 20

Question 9

Atlanto-axial joints
Type of joint?
Allows what movement?
Movement of the joint is limited by what?

Answer 9

•2x lateral atlanto-axial joint = gliding synovial joint.
•1x median atlanto-axial joint = pivot joint.
•Permits lateral rotation of head (i.e. shaking head saying “no”).
Slide 21

Question 10

Transverse ligament of Atlas

Answer 10

•Holds odontoid process (dens) in place
•Allows rotation
Slide 23

Question 11

Alar ligament

Answer 11

Attaches the dens to the occipital condyles
-limits atlanto-axial joints
Slide 23

Question 12

Cruciform (cross) ligament

Answer 12

Transverse one is strong, longitudinal ligament is weak.

Slide 24

Question 13

Tectorial membrane

Answer 13

Continuation of the posterior longitudinal ligament
from C2 through foramen magnum to floor of cranium
Slide 25

Question 14

How do different parts of the vertebrae develop?

Answer 14

•Sclerotomes => vertebra.
•Notochord between vertebra => nucleus pulposus.
•Birth = 3 bony parts connected by cartilage (C3-C6).
•Halves of vertebral arch fuse at 3-5-years-old.
•Vertebral arch fuses to body at 3-6-years-old.
Slide 26

Question 15

Scoliosis

Kyphosis “Hunch-back”

Lordosis “Sway-back”
•Accentuated extension of lumbar spine.
•Aetiology: weakened trunk muscles, late pregnancy, obesity.

Answer 15

Scoliosis
•Accentuated lateral and rotational curve of the thoracic or lumbar spine.
•Aetiology: genetic, trauma, idiopathic; occurs in adolescent girls more than boys

Kyphosis “Hunch-back”
•Accentuated flexion of thoracic spine.
•Aetiology: poor posture, osteoporosis.

Question 16

What is osteoarthritis?

Answer 16

•Progressive erosion of cartilage in joints of spine, fingers, knee and hip (most commonly).
•In spine => can lead to spinal nerve impingement.
Slide 31

Question 17

Spondylolysis
Slide 32

Spondylolithesis

Answer 17

• Affects 3-6% population.
• Defect where vertebral arch becomes separated from it’s body.
• 85-95% cases at L5; 5-15% at L4.

Spondylolithesis:
Anterior or posterior displacement of vertebrae in relation to the vertebrae below

Question 18

IV disc herniation

Answer 18

• Peripheral tears (mostly posterolateral) of anulus fibrous allows for extrusion and herniation of nucleus pulposus which may impinge spinal nerves.
• Lumbar disc herniations are common and result in pain over SI joint, hip, posterior thigh and leg.

Question 19

Describe the blood supply to the vertebrae.
Nutrient arteries branch from? And supply what?
Slide 26

Answer 19

Slide 26
Nutrient arteries branching from the anterior vertebral canal branch supply blood to the red bone marrow with the vertebral bodies

Question 20

Venous drainage

Answer 20

3 anterior spinal veins 
3 posterior spinal veins 
Longitudinal 
Internal vertebral venous plexus 
-communicates with Duran sinuses and vertebral veins in cranium AND external vertebral venous plexuses on external surface of vertebrae.

Question 21

Vertebral venous plexus

Basic external veins form were?

Answer 21

Basic external veins form were?

Form WITHIN vertebral bodies. They emerge from foramina on surfaces

Question 22

Venous drainage of spinal cord

Answer 22

Spinal veins form venous plexuses along the vertebral column both inside (internal venous plexus) and outside (external venous plexus) of vertebral canal.
Veins draining spinal cord➡ internal and external venous plexus ➡ vertebral veins of neck.