A contractual provision in an insurance policy that denies coverage for certain perils, persons, property or locations. Most exclusions exist simply to remove coverage for above-average risks which are not anticipated in average rates and premiums. In some cases, the coverage is available for an additional charge. Common policy exclusions include: war and acts of war, self-inflicted injury and aviation.
Intervertebral disk. An intervertebral disk acts as shock absorber between each of the vertebrae in the spinal column by keeping the vertebrae separated when there is impact from activity. They also serve to protect the nerves that run down the middle of the spine and intervertebral disks. There are a total of 24 disks in the human spine.
Annulus Fibrosus and Nucleus Pulposus. Intervertebral discs are composed of an annulus fibrosus and a nucleus pulposus. The annulus fibrosus is a strong radial tireâlike structure made up of lamellae; concentric sheets of collagen fibers connected to the vertebral end plates.The sheets are orientated at various angles.he annulus fibrosus encloses the nucleus pulposus. Although both the annulus fibrosus and nucleus pulposus are composed of water, collagen, and proteoglycans (PGs), the amount of fluid (water and PGs) is greatest in the nucleus pulposus. PG molecules are important because they attract and retain water.