Biomedical Engineering Reference
In-Depth Information
a
b
Ligamentum Flavum
Intertransverse
Ligament
Cartilaginous
End Plate
Facet
Capsulary
Ligament
Posterior
Longitudinal
Ligament
Annulus Fibrosus
Interspinous
Ligament
Nucleus Pulposus
Supraspinous
Ligament
Anterior
Longitudinal
Ligament
Lamellae
Intervertebral disk
Annulus
fibrosus
c
Hyaluronan
Nucleus
pulposus
Spinal
cord
Swelling Pressure
Aggrecan
Transverse
process
Superior
articular facet
Link Protein
Water Drawn
into Tissue
Collagen
Spinous
process
Tension
Fig. 1 (a) Function spinal unit composed of cartilagenous, boney, ligamentous, and neural
structures Available from
http://www.spinediagrams.com/
and
http://www.healthcentral.com/
osteoarthritis/h/c4-c5-intervertebral-disc-degenerative-disease.html
.
Last viewed 26 AUG 2011.
(b) Image taken during the dissection of a porcine IVD that clearly indicates the delineation of the
outer annulus fibrosus and central gelatinous nucleus pulposus. (c) Nucleus pulposus extracellular
matrix composed of collagen type II (
green
), aggrecan (red bottle-brushes), hyaluronan (
blue
) and
link protein (
yellow
) which endow the tissue with its physico-chemical properties including its
characteristic swelling pressure [
12
]
Table 1 Summary of the regional differences in the biochemical composition of the intervertebral
disc
Component
Nucleus pulposus
Annulus fibrosus
Water (%)
70-90
50-60
Collagen (%)
15 (collagen II)
65 (collagen I)
Proteoglycan (%)
60
15
Non-collagen proteins/elastin (%)
25
20
Cell morphology
Chondrocyte-like
Fibroblast-like
