Arthrology of the Vertebral Column: Intervertebral Disc Flashcards
What is the maximum number of ligaments identified with a vertebral couple?
8
What is the reason that nine common ligaments are identified but only eight will be attached at any specific vertebral couple?
the ligamentum nuchae and supraspinous ligaments attach to the spinous tubercles, but only one of these will be identified at a single vertebral couple
What is the number of true intervertebral discs identified in the adult?
twenty-three
In the adult, which vertebral levels will demonstrate a true intervertebral disc?
Those between C2 and S1 inclusive
What is the percent of the intervertebral disc height contribution to the length of each region of the vertebral column?
cervical… 22-25%; thoracic…20%; lumbar…33%
What What are the names of the central, peripheral, and horizontal zones of the intervertebral disc?
nucleus pulposus…central; annulus fibrosus…peripheral zone; cartilaginous end plate… horizontal zone
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 under deformation conditions
What cell is associated with the nucleus pulposus till about age eleven?
notochord cells
What type of collagen is dominate in the nucleus pulposus?
collagen type II
What is the organization pattern for collagen fibers in the nucleus pulposus?
they are irregularly orientated and randomly scattered
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 processes; 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?
the typically have a binding site for hyaluronic acid and are thus aggregated
Which type of collagen fiber is dominant in the annulus fibrosus?
collagen type I
what is the organizational pattern for the collagen fibers in the annulus fibrosus?
they are parallel with on another in a single lamellas and angled
What is the organization of collagen fibers between lamellae?
collagen fibers will be angled in the opposite direction such that a spiral– counter spiral 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 principle 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 disc, the greater the variety of receptor endings
What part of the intervertebral disc is innervated by the recurrent meningeal/ ainu-vertebral/ sinus vertebral nerve?
the outer lamellae of the annulus fibrosus 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 rams, fibers from the white rams communicates, fibers from the paradiscal rams communicans, fibers from the gray rams communicans
What is the name given to the white ramus communicans which becomes embedded within the annulus fibrosus of the intervertebral disc?
the paradiscal rams communicans
What part of the intervertebral disc is innervated by fibers from paradiscal rams 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 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 the sclerotomites?
the intrasclerotomal fissure or fissure of von Ebner
What does the intrasclerotomal fissure or 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 the fissure of von Ebner
