ARTHOLOGY OF THE VERTEBRAL COLUMN - intervertebral disc

Question 1

In the fetus, which vertebral levels will demonstrate intervertebral discs?

Answer 1

those between C2 and Co1 inclusive

Question 2

What is the number of true intervertebral discs identified in the adult?

Answer 2

twenty-three

Question 3

In the adult, which vertebral levels will demonstrate a true intervertebral disc?

Answer 3

those between C2 and S1 inclusive

Question 4

What is the percent of intervertebral disc height contribution to the length of each region of the vertebral column?

Answer 4

cervical 22-25%
thoracic 20%
lumbar 33%

Question 5

What si the effect of aging on the intervertebral disc nucleus pulposus?

Answer 5

it becomes more fibrous as water and proteoglycan concentrations diminish

Question 6

What is the cervical nucleus pulposus composed of?

Answer 6

fibrocartilage

Question 7

What is the consequence of non-aggregated glycosaminoglycans in the lumbar nucleus pulposus?

Answer 7

the nucleus pulposus will lose water under deformation conditions

Question 8

What cell is associated with the nucleus pulposus until about age eleven?

Answer 8

notochord cells

Question 9

Which type of collagen is dominant in the nucleus pulposus?

Answer 9

collagen type II

Question 10

What is unusual about the cervical annulus fibrosus?

Answer 10

it lacks any lamellar or layered organization

Question 11

What is the appearance of the cervical annulus fibrosus?

Answer 11

a horse-shoe with the anterior margin thick and the lateral margins tapering to the uncinate processes; the posterior margin is thin

Question 12

What is the organization of the lumbar annulus fibrosus?

Answer 12

it has 12-14 concentric cylindrical lamellae

Question 13

What is the consequence of aggregated glycosaminoglycans in the lumbar annulus givrosus?

Answer 13

the annulus fibrosus will retain water under deformation conditions

Question 14

Which type of collagen is dominant in the annulus fibrosus?

Answer 14

collagen type I

Question 15

What is the organization of collagen fibers between lamellae?

Answer 15

collagen fibers will be angled in the opposite direction such that a spiral - counterspiral organization is observed

Question 16

What is the organizational pattern for collagen fibers in the annulus fibrosus?

Answer 16

they are parallel with one another in a single lamellus and angled

Question 17

What is the average angle of collagen fibers within the annulus fibrosus?

Answer 17

they average 50 to 60 degrees

Question 18

What is the principal type of collagen fiber within the cartilage end plate?

Answer 18

the type II collagen fiber

Question 19

What is the direction of collagen fibers within the cartilage end plate?

Answer 19

collagen fibers are aligned anterior to posterior

Question 20

What cell type is associated with the cartilage end plate?

Answer 20

chondrocytes

Question 21

What is the earliest indicator of intervertebral disc pathology or degeneration?

Answer 21

changes in the histology of the cartilage end plate

Question 22

What part of the intervertebral disc is the “growth plate”

Answer 22

the transition zone

Question 23

What part of the intervertebral disc is innervated?

Answer 23

the outer lamellae of the annulus fibrosus

Question 24

What are the types of receptor endings in the intervertebral disc?

Answer 24

nociceptors and proprioceptors

Question 25

What is the relationship between size of the intervertebral disc and receptor endings

Answer 25

the larger the disc, the greater the variety of receptor endings

Question 26

What is the proposed function of receptor ending density in the anterior part of the intervertebral disc?

Answer 26

they provide feedback during extension

Question 27

What forms the posterior neural plexus of the vertebral column?

Answer 27

the sinu-vertebral nerve (sinus vertebral nerve, recurrent meningeal nerve

Question 28

What forms the anterior neural plexus of the vertebral column?

Answer 28

fibers from the ventral primary ramus

Question 29

What is the name given to the white ramus communicans which becomes embedded within the annulus fibrosus of the intervertebral disc?

Answer 29

the paradiscal ramus communicans

Question 30

What innervates the outer lamellae of the annulus fibrosus at the lateral part of the intervertebral disc?

Answer 30

fibers from the ventral primary ramus, fibers from the white ramus communicans, fibers from the paradiscal ramus communicans, fibers from the gray ramus communicans

Question 31

What structure is formed following migration of sclerotomes to surround the notochord?

Answer 31

the perichordal blastema

Question 32

What is formed within the perichordal blastema between the sclerotomites?

Answer 32

the intrasclerotomal fissure or fissure of von Ebner

Question 33

What does the intrasclerotomal fissure or fissure of von Ebner become?

Answer 33

the perichordal disc

Question 34

What part of the intervertebral disc will the notochord form?

Answer 34

the nucleus pulposus

Question 35

What part of the intervertebral disc will the perichordal disc form?

Answer 35

the annulus fibrosus

Question 36

What is the earliest indicator of the position of the adult intervertebral disc?

Answer 36

the intrasclerotomal fissure or fissure of von Ebner