The individual bones That include the spine are called vertebrae. Each vertebrae except the top two in the neck are separated by a pillow, an intervertebral disc. The exterior of this disk is surrounded by fibrous, ligamentous tissue called the annular fibers termed as such from the same root word from which we get yearly or year round. In some ways discs resemble car tires because they absorb shock and allow the spine to bend and move, but rather than being full of atmosphere like a tire the interior or nucleus of a spinal disc is full of a jelly-like protein substance that is designed to absorb shock. Desiccation is a scientific word meaning dry which means the interior of the disk is drying out. In time the annular fibers also start to dry out, lose their elasticity and are susceptible to cracks or tears which result in a bulging out or herniation of the disc tissue.
Disc desiccation is The very first step in degenerative disk disease and is characterized via MRI (Magnetic Resonance Imaging), a noninvasive diagnostic technique that produces computerized images of internal body cells and is based on nuclear magnetic resonance of atoms in the body. This technique can be imagined as a type of advanced x ray but is rather induced by the application of radio waves, not x-rays. Similar in some ways to sonar on a submarine the body is pinged by those radio waves. The signals that bounce back are different determined by how wet or dry the tissue is and also the magic of computers that the information is collected and the computer assigns colour to the pixels. Very wet tissue like body fat is left white and totally dry tissue is left black with many, many shades of gray in between. Thus, a healthy hydrated disk will look white whereas a dry disk will appear very black or grey.
As a disk loses water Content it begins to drop height and the vertebra get closer together. This is readily seen on both x ray and MRI, and creates the appearance of the disk wearing away but actually no tissue has really disappeared – it is shrunk in size exactly in exactly the same manner that a plump plum when dried becomes a shriveled prune. This is the second phase of disk degeneration.
A sterile, thin disc is Unable to perform its job of absorbing shock and as the degenerative changes advancement can eventually get to the point at which the ordinary jolt of the heel striking the ground which happens during regular walking cause’s pain. More substantial impacts like dropping the body weight from step to step while descending stairs and an infinite range of other everyday activities could lead to sudden sharp, shooting pains in what many patients describe as bone on bone and while, perhaps, not technically appropriate never-the-less effects in mechanical strain to the joints of the spine and the supporting ligaments. This desiccant pouch stress leads to osteoarthritis, the next step in degenerative disk disease.