Arthrology/Innervation of the Vertebral Column Flashcards
What is the maximum number of common ligaments identified with a vertebral couple?
Eight
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?
23
What is the percent of intervertebral disc height contribution to the length of each region of the vertebral column?
Cervical: 22-25%
Thoracic: 20%
Lumbar: 33%
What is the cervical nucleus pulposus composed of?
Fibrocartilage
What is the water concentration in the lumbar nucleus pulposus at birth and after thirty?
Birth: 88%
Thirty: 70%
What is the organizational pattern for glycosaminoglycans in the lumbar nucleus pulposus?
They typical lack a binding site for hyaluronic acid and are thus non-aggregated
What cell is associated with the nucleus pulposus until about age eleven?
Notocord cells
Which type of collagen is dominant in the nucleus pulposus?
Collagen type II
What is unusual about the cervical annulus fibrosus?
It lacks any lamellar or layered organization
What is the appearance of the cervical annulus fibrosus?
A horse-shoe with an anterior margin thick and a 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
Why is the posterior part of the lumbar annulus fibrosus more susceptible to rupture, herniation, prolapse, or protrusion?
The posterior margin of each lamellus is thin and the posterior longitudinal ligament is also less developed
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 int he lumbar annulus fibrosus?
They typically have a binding site for hyaluronic acid and are thus aggregated
What is the consequence of aggregated glycosaminoglycans in the lumbar annulus fibrosus?
The annulus fibrosus will retain water under deformation conditions
Which type of collagen is dominant in the annulus fibrous?
Collagen type I
What is the organizational pattern for collagen fibers in the annulus fibrosus?
They are 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 obsevred
What is the average angle of collagen fibers within the annulus fibrosus?
They average 50 to 60 degrees
What is the origin for the cells of the annulus fibrosus?
Sclerotomites
What cell type is associated with annulus fibrosus?
Fibroblast and fibrocyte
What is the cartilage end plate derived from?
The epiphyseal plate
What part of the vertebral body will the cartilage end plate cover?
The cancellous bone at the top or bottom of the vertebral body
What is the principal type of collagen fiver within the cartilage end plate?
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 earliest indicator of intervertebral disc pathology or degeneration?
Changes in the histology of the cartilage end plate
What part of the intervertebral disc is innervated?
The outer lamellae of the annulus fibrosus
What part of the cervical intervertebral disc is highly innervated?
The middle third of the annulus fibrosus
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 is the proposed function of receptor ending density in the anterior part of the intervertebral disc?
They provide feedback during extension
What are the sources of innervation of the intervertebral disc?
The sinu-vertebral nerve (sinus vertebral nerve, recurrent meningeal nerve)
Fibers from the ventral primary ramus
Fibers from the white ramus communicans
Fibers from the paradisiacal ramus communicans
Fibers from the gray ramus communicans
What nerve(s) have been shown to give off the sinus vertebral/sinu-vertebral/recurrent meningeal nerve?
The mixed spinal nerve Ventral primary ramus Dorsal primary ramus Gray ramus communicans White ramus communicans
The recurrent meningeal/sinu-vertebral/sinus vertebral nerve has typically been shown to originate from which source?
The gray ramus communicans
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 part of the intervertebral disc is innervated by fibers from the ventral primary ramus?
The outer lamellae of the the annulus fibrosus at the anterior and lateral part of the intervertebral disc
What innervated the annulus fibrosus at the lateral part of the intervertebral disc?
Fibers from the ventral primary ramus
Fibers from the paradisiacal ramus communicans
Fibers from the gray ramus communicans
What part of the intervertebral disc is innervated by fibers from the white ramus communicans?
The outer lamellae of the annulus fibrosus at the lateral part of the intervertebral disc
What is the name given to the white ramus which becomes embedded within the annulus fibrosus of the intervertebral disc?
The paradisiacal ramus comminicans
