Day 4 (pg 155) Flashcards
What is the 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 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
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 in 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 fibrosis?
the annulus fibrosus will retain water under deformation conditions
Which type of collagen is dominant in the annulus fibrosis?
collagen type I
What is the organization 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 observed
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 the annulus fibrosus?
fibroblast and fibrocyte
What is the cartilage end plate derived from?
the epiphyseal plate
