Intervertebral Disc Flashcards
What is the water concentration in the lumbar nucleus pulposus at birth and after thirty?
birth=88%, thirty=70%
What is the consequence of non-aggregated glycosaminoglycans in the lumbar nucleus pulposus?
the nucleus pulposus will loose water uder deformation conditions
What cell is associated with nucleus pulposus until about age eleven?
notochord cells
Which type of collagen is dominant in the nucleus pulposus?
type II
What is the appearance of the cervical annulus fibrosus?
a horse-shoe with the anterior margin thick and the lateral margins tapering to the uncinate process; the posterior margin is thin
What compensates for the thinness of the posterior part of the cervical annulus fibrosus?
posterior longitudinal ligament
What is the organization of the lumbar annulus fibrosus?
it has 12-14 concentric cylindrical lamellae
What is the water concentration in the lumbar annulus fibrosus at birth and after thirty?
birth=78%, thirty 70%
What is the organizational pattern for glycosaminoglycans in the lumbar annulus fibrosus?
they typically have a binding site for hyaluronic acid and are thus aggregated
Which type of collagen is dominant is the annulus fibrosus?
type I
What is the organizational pattern for collagen fibers in the annulus fibrosus?
they are a parallel with one another in a single lamellus and angled
What is the organization of collagen fibers between lamellae?
collagen fibers will be angled in the opposite direction such that a spiral- counterspiral organization is observed
What is the attachment site for collagen fibers within the annulus fibrosus?
collagen fibers of the outer lamellae will become Sharpey’s fibers and penetrate the epiphyseal rims; collagen fibers of the inner lamellae will attach to the cartilaginous end plate
What is the origin for the cells of the annulus fibrosus?
sclerotomites
What is the principal type of collagen fiber within the cartilage end plate?
the type II collagen fiber
What is the direction of collagen fibers within the cartilage end plate?
collagen fibers are aligned anterior to posterior
What is the attachment site for collagen fibers of the inner lamellae of the annulus fibrosus?
the cartilaginous end plate
What are the types of receptor endings in the intervertebral disc?
nociceptors and proprioceptors
What is the relationship between size of the intervertebral disc and receptor endings?
the larger the disc, the greater the variety of receptor endings
What part of the intervertebral disc is innervated by the recurrent meningeal/sinu-vertebral/sinus vertebral nerve?
the outer lamellae of the annulus fibrosus at the posterior part of the intervertebral disc
What forms the anterior neural plexus of the vertebral column?
fibers from the ventral primary ramus
What forms the lateral neural plexus of the vertebral column?
fibers from the ventral primary ramus, fibers from the white ramus communicans, fibers from the paradiscal ramus communicans, fibers from the gray ramus communicans
What is the name given to the white ramus communicans which becomes embedded within the annulus fibrosus of the intervertebral disc?
the paradiscal ramus communicans
What part of the intervertebral disc is innervated by fibers from the paradiscal ramus communicans?
the outer lamellae of the annulus fibrosus at the lateral part of the intervertebral disc
How does the intervertebral disc attach to the vertebral body?
Sharpey’s fibers from the outer lamellae of the annulus fibrosus are firmly embedded into the epiphyseal rims of the adjacent vertebral bodies
Based on histology, what is the classification of the intervertebral disc?
a cartilaginous (amphiarthrosis) symphysis
What are the divisions of the embryonic somite?
the sclerotome, myotome, and dermatome
What structure is formed following migration of sclerotomes to surround the notochord?
the perichordal blastema
What is formed within the perichordal blastema between sclerotomites?
the intrasclerotomal fissure or fissure of von Ebner
What does the intrasclerotomal fissure of fissure of von Ebner become?
the perichordal disc
What will the dense sclerotomite become?
the upper part of the vertebral segment forming below
What structure forms following migration and subsequent mixing of the sclerotomites?
the vertebral blastema
What part of the intervertebral disc will the notochord form?
the nucleus pulposus
What part of the intervertebral disc will the perichordal disc form?
the annulus fibrosus
What is the earliest indicator of the position of the adult intervertebral disc?
the intrasclerotomal fissure or fissure of von Ebner
