Friday, June 12, 2009
Disc Degeneration - Important Information
The lack of shock absorption by the discs causes increased stress on the facet joints (a gliding joint between each vertebra) of the spine, and results in facet joint degeneration.
These changes may eventually cause pressure on the nerve roots (nerves that exit from the spinal cord) and may result in sciatic-type pain (pain down the leg). This condition is often referred to as Degenerative Disc Disease.
Disc Herniation, Protrusion, Prolapse, & Extrusion
A disc protrusion (also known as a disc bulge) occurs when the inner material of the disc starts to push out through the outer wall of the disc, creating a bulge in the disc.
In most cases this disc bulge is completely symptomless, and causes no pain or lack of function. In fact, most individuals over the age of forty have disc bulges.
In some cases, a disc bulge or protrusion compresses a nerve and causes significant neurological dysfunction. A disc bulge that compromises the function of the nerve is normally considered to be a surgical emergency, and requires immediate surgical intervention to correct the problem. This type of condition, although rare, must be evaluated by a qualified medical practitioner.
Problems occur when these disc protrusions start to tear or fragment. A herniated disc occurs when the inner material of the disc (the nucleus pulposus) starts to push through the outer fibers of the disc (the annulus fibrosus). Most disc herniations occur at the two lower levels of the spinal column.
When the outer layers of a disc rupture, the inner center of the disc may move out and press upon a nerve. This condition is known as disc prolapse or a protruding disc. In such cases, the material inside the disc can sometimes extrude into the spinal canal.
In rare cases a severe prolapse will press on the nerves which control bowel and bladder function, resulting in severe muscle atrophy. These are rare events and are considered to be surgical emergencies. The majority of disc prolapses do not fit into this category.
In yet other cases, a disc may extrude right through the outer fibers of the disc, and a piece may break off completely. When this occurs, the extruded piece of disc can interfere with the function of the nearby nerves. This condition - sequestered disc - requires surgical intervention if it is causing neurological dysfunction, and is a problem that cannot be resolved with just soft-tissue manipulation.
However, the most important point to be made is that most cases that involve a disc bulge or protrusion do not require surgery. In fact there are a couple of common myths about disc protrusions that we should consider:
The first myth is that the presence of a large disc protrusion – as often seen on MRI or CAT scan images – is an indication that this problem cannot be resolved with conservative care (non-surgical).
In reality, research is showing the exact opposite to be true. The larger the disc protrusion, the greater the reduction in protrusion size after conservative treatment.
The second myth is that the extruded and sequestered disc fragments are less likely to resolve than the contained protrusions.
In actuality, the migrating fragments actually resolve more frequently and faster than the contained protrusions. The reason for this is, the larger the disc protrusion, the greater the degree of inflammation around the protrusion. Once disc fragments have broken off, inflammation around the fragments and the disc decreases, allowing the body to reabsorb the fragments more easily.
MRIs are commonly used as a diagnostic tool for identifying where a disc protrusion is occurring. However, a protruding disc is not always the true cause of the pain and discomfort. To arrive at a proper diagnosis, it is very important that the practitioner correlate the MRI results against the comprehensive physical examination and clinical symptoms exhibited by the patient.