Day 38 (intervertebral disc: Annulus fibrosus, cartilaginous end plate and transition zone, innervation)

Question 1

What compensates for the thinness of the posterior part of the cervical annulus fibrosus?

Answer 1

posterior longitudinal ligament

Question 2

What is the organization of the lumbar annulus fibrosus?

Answer 2

it has 12-14 concentric cylindrical lamellae

Question 3

What is the water concentration in the lumbar annulus fibrosus at birth and after thirty?

Answer 3

birth…78%; thirty…70%

Question 4

What is the organizational pattern for glycosaminoglycans in the lumbar annulus fibrosus?

Answer 4

they typically have a binding site for hyaluronic acid and are thus aggregated

Question 5

Which type of collagen is dominant in the annulus fibrosus?

Answer 5

collagen type I

Question 6

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

Answer 6

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

Question 7

What is the organization of collagen fibers between lamellae?

Answer 7

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

Question 8

What is the attachment site for collagen fibers within the annulus fibrosus?

Answer 8

collagen fibers of the outer lamellae will become Sharpey’s fibers and penetrate the epiphyseal rims; collage fibers of the inner lamellae will attach to the cartilaginous end plate

Question 9

What is the origin for the cells of the annulus fibrosus?

Answer 9

sclerotomites

Question 10

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

Answer 10

the type II collagen fiber

Question 11

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

Answer 11

collagen fibers are aligned anterior to posterior

Question 12

What is the attachment site for collagen fibers of the inner lamellae of the annulus fibrosus?

Answer 12

the cartilaginous end plate

Question 13

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

Answer 13

nociceptors and proprioceptors

Question 14

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

Answer 14

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

Question 15

What part of the intervertebral disc is innervated by the recurrent meningeal/sinu-vertebral/sinus vertebral nerve?

Answer 15

the outer lamellae of the annulus fibrosus at the posterior part of the intervertebral disc

Question 16

What forms the anterior neural plexus of the vertebral column?

Answer 16

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 17

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

Answer 17

the paradiscal ramus communicans

Question 18

What part of the intervertebral disc is innervated by fibers from the paradiscal ramus communicans?

Answer 18

the outer lammellae of the annulus fibrosus at the lateral part of the intervertebral disc