Vertebral Column and Spinal Cord

Question 1

Number of vertebrae in each area of the vertebral column?

Answer 1

7 Cervical (C1-C7)
12 Thoracic (T1-T12)
5 Lumbar (L1-L5)
5 Sacral (S1-S5) - fused into sacrum
4 Coccygeal (Co) fused into one coccyx

Question 2

roles of the subdivisions of the vertebral arch?

Answer 2

Pedicle - attaches transverse process to body of vertebra
Lamina - attaches transverse process to spinous process
Paired sup. and inf. articular processes and notches
Spinous and transverse processes - for attachment of muscles and ligaments

Question 3

Distinctive feature(s) of the cervical vertebrae?

Answer 3

Transverse foramen
bifid spinous process on C2
smalles of the movable vertebrae

Question 4

What passes through the transverse foramen?

Answer 4

The vertebral vessels (artery + vein)

Sympathetic nerve plexuses

Question 5

Describe what makes C1 and C2 atypical vertebrae?

Answer 5

C1 (atlas) - facets for articulation with occipital condyle

• facet for dens of C2
• NO vertebral body
• NO intervertebral disc between C1 and C2

C2 (Axis) - 2 large flat surfaces, upon which atlas rotates
- superiorly protruding Dens (odontoid process), held in place by transverse ligament of atlas

Question 6

Distinguishing features of thoracic vertebrae?

Answer 6

2 demi-facets on each side of vertebral body for articulation with head of their own rib and the rib below
transverse process also has facet for articulation with tubercle of the rib
vertebral canal/body more heart shaped
spinous process is long and extends postero-inferiorly

Question 7

Distinguishing features of lumbar vertebrae?

Answer 7

Much larger in size
no facets for articulation with ribs
vertebral canal triangular
L5 has large thick stocky spinous process for attachment of iliolumbar ligaments

Question 8

What holds vertebrae together?

Answer 8

Facet joints
Intervertebral discs
Ligaments

Question 9

What are facet joints?

Answer 9

aka ZYgapophyseal joints

connect superior and inferior articular processes of adjacent vertebrae

Question 10

Role and components of intervertebral discs?

Answer 10

provide flexibility to the spine
act as shock absorbers

Peripherally - Annulus Fibrosus (outer ring of collagen and fibrocartilage)
Centrally - Nucleus Pulposus (gelatinous to absorb compression forces between vertebrae)

Question 11

How many joints does a typical vertebrae have?

Answer 11

6 Joints

• 4 articular - 2 above, 2 below
• 2 symphyses - one above, one below between discs

Question 12

Ligaments binding together the vertebral column?

Answer 12

Anterior Longitudinal Ligament
Posterior Longitudinal Ligament
Ligamentum Flavum
Ligamentum Nuchae
Interspinous ligaments

Question 13

Description of Anterior Longitudinal Ligament?

Answer 13

runs down anterior surface of vertebral column
from inferior occipital to sacrum
holds together verteral bodies and intervertebral discs
broadens as it descends

Question 14

Description of Posterior Longitudinal Ligament?

Answer 14

runs down posterior surface of vertebral column, along bodies
from back of axis (c2) to back of sacrum
narrows as it descends
holds together vertebral bodies and intervertebral discs

Question 15

Description of Ligamentum Flavum?

Answer 15

Extends from lamina to lamina of same vertebrae
from C2 to first segment of sacrum
aids in preservation of upright posture
very elastic so aids in bending back up
prevents spinal cord from buckling

Question 16

Description of Ligamentum Nuchae?

Answer 16

from external occipital protruberance to spinous process of C7
aids in sustaining the weight of the head
helps in running

Question 17

Description of interspinous ligaments?

Answer 17

Connect adjacent spinous processes
extend from root to apex of each spinous process
limit flexion of the spine

Question 18

At what vertebral level does the spinal cord end in:

• the newborn?
• the adult?

Answer 18

Newborn - L3/L4

Adult - L1/L2

Question 19

Contents of the subdural space?

Answer 19

It is a potential space and so doesn’t contain anything

Question 20

Contents of the subarachnoid space?

Answer 20

CSF
Trabeculae - interconnect arachnoid mater and pia mater
- thin delicate strips of tissue
- blood vessels suspended from these (spinal arteries)

Question 21

Contents of the epidural space?

Answer 21

Lymphatics
loose connective tissue
fat
venous plexuses
spinal nerve roots

Question 22

Blood supply of the spinal cord?

Answer 22

1 anterior and 2 posterior spinal arteries

Question 23

origin of the spinal arteries?

Answer 23

Anterior spinal artery (ASA) - arises from branches of vertebral arteries and travels along anterior aspect of the spinal cord

Posterior Spinal Ateries (PSA) - also vertebral arteries, adjacent to medulla oblongata

Both are reinforced by radicular branches of intercostal and lumbar arteries

Question 24

Describe the venous drainage of the spinal cord?

Answer 24

Two channels run longitudinally in anterior and posterior sulci
via medullary and radicular veins these drain into internal venous plexus in epidural space
this drains into SVC

Question 25

Describe how the spinal nerves exit the spinal cord

Answer 25

Spinal nerves from C1-7 leave the vertebral column above their corresponding vertebrae
- 7 vertebrae but 8 nerves, as C8 leaves below C7, but above T1
From T1 and below the rest leave below their corresponding vertebrae

Question 26

What is the cauda equina?

Answer 26

Formed from dorsal and ventral spinal nerve roots caudal to the spinal cord termination at T1
consists of L2-L5, S1-S5 and coccygeal nerve
all emerge from lumbar enlargement