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Spinal Disc Function
Usually only mentioned in connection with back pain, our spinal discs tend to have a bad reputation. While this reputation may to some extent be deserved, it warrants pointing out that our discs - we have 23 of them - give the otherwise rather hard and stiff series of bone blocks (vertebrae) and tight ligaments that make up our spines a remarkable degree of flexibility, and thereby make an essential contribution to our capacity to move about the world the way we do. |
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Disc Herniation
The biomechanical properties of our discs change throughout the day and, regrettably, throughout our lives. Aging from the moment of our births, our spinal discs undergo a degenerative process that is more extensive than that seen in all other tissue types. While our discs are supplied with nutrients by their own blood vessels during the embryonic phase, the supply of water and nutrients in adults takes place exclusively via diffusion.
Our discs contract during the day as they carry the weight of our bodies and expand like a sponge as they take on water in their unloaded state at night. The difference in the size of our discs in the morning and evening may vary by several centimeters. As we age, the gelatinous core of our discs gradually shrinks. This brings about changes in the overall structure's biomechanical properties. Exposed to additional stress, the fiber ring (annulus) may bulge (i.e. like a rubber ball we press between our hands) and begin to exhibit tears and fissures. This sets the stage for disc herniation, which occurs when a portion of the gelatinous core pushes out beyond the boundaries of the fiber ring and into the spinal canal.
Back Pain Associated with Disc Protrusion and Herniation 
The protrusion of the disc or the extrusion of disc material into the spinal canal can pinch highly sensitive nerve roots and cause considerable pain both at the point of impact and in the areas of the body (e.g. the legs) that are served by the nerves in question. In addition to this, sensory and functional disturbances, including numbness, tingling and a loss of muscle strength, may occur depending on the degree to which the nerve pathways that carry signals to and from our brains are compromised.
The extrusion of the gelatinous material that is normally contained within the annulus leads to sensory and functional disturbances more frequently than disc protrusion (bulging). Moreover, the disc material that is extruded into the spinal canal (either in the direction of the head or the feet) may become detached. This peculiarity, known as sequestered herniation, can cause nerve root irritation at a distance from the damaged disc. It warrants pointing out in this context that some people may experience no symptoms whatsoever when disc herniation occurs. Investigations of the affected nerve tissue in such cases suggest that an adaptive process can take place whereby the pain receptors in the impacted tissue recede. This emphasizes the importance of using infiltration therapy to confirm or rule out the need for disc surgery.
Diagnosing Disc Herniation
The task of diagnosing disc herniation should only be performed by a specialist in the context of a thorough examination that may involve consultation with specialists in related fields of medicine. An MRI or a CAT scan can serve to support a diagnosis and determine which disc is involved. Contrast media may also be used in the visualization of the disc and the spinal canal. Surgery should not be performed for disc herniations that can only be detected using MRI and that involve no symptoms.
Treatment for Herniated Discs:
Treatment for herniated discs generally focuses on removing or reducing the extruded disc material so as to relieve the pinched nerve root. Several minimally invasive procedures may be used depending on the location and extent of the herniation or protrusion involved. These include nucleoplasty, Racz catheter treatment, disc-FX treatment, endoscopic disc removal, disc replacement and open microsurgical removal of extruded material. However, given that most herniated discs do respond favorably to conservative forms of treatment, it is important to exercise caution when considering surgery. On the other hand, it may be necessary in the case of disc herniations that lead to functional disturbances - such as a loss of muscle strength and lameness - to remove the extruded disc material as soon as possible so as to prevent irreversible damage to the affected nerves.
