A lumbar herniated disc is quite common. It may or may not be
Before we discuss a herniated lumbar disc or bulging disc you need to understand a little anatomy.
Your spine is comprised of six cervical vertebrae, 12 thoracic, and five lumbar, the sacrum, coccyx and the ilium. Between all of the vertebrae, except for the first and second cervical, are what is known as your discs.
Each disc connects a vertebra from above to another directly below it. These discs are firmly attached to the body of the vertebrae with very strong fibers that run completely around the bodies.
The body of the vertebra is the large front part. In the center of each disc is a gel-like material known as the nucleus pulposus.
Ideally, the disc fibers encircling the adjacent vertebrae should remain very strong and thick throughout your life. This will contain the nucleus pulposus and keep it from escaping from its confines.
With a lumbar herniated disc or a bulging disc the gel substance pushes outward against the outside fibers causing it to bulge. This is very similar to a bubble that develops on the outside wall of a tire when it has become thinned, worn and weak.
In the past a herniated disc was referred to as a "slipped disc".
Slipped discs are actually impossible and this term should not be used. Because of the disc attachment to the body of the vertebra discs are impossible to glide or slip.
Due to an injury, natural weakness, poor nutrition or oxygen deprivation, or the drying of the disc that occurs with aging the outside wall of the disc is weaker than it should be.
The internal pressure of the disc forces the nucleus pulposus to push the disc outward. When this happens it may cause little or no discomfort or if it presses against a nerve it can cause mild to excruciating pain and other symptoms such as numbness, pins and needles, tingling, muscle weakness, loss of feeling, or diminished or absent reflexes.
With complete tearing of the outside ring the nucleus can
herniate through or prolapse. Symptoms may be present or absent usually depending on whether there is nerve contact or not.
Pain may be noticed even in the absence of nerve pressure due to a
chemically induced inflammation.
Your body will respond by producing inflammation which is its way of
trying to dissolve and resorb the escaped nucleus.
If the lumbar herniated disc is large the symptoms are usually more intense. A very, large disc herniation tends to be more serious and often requires surgical removal.
Sometimes a lumbar disc herniation, even if large, may be painless. It is estimated that the majority of the adult population has a lumbar disc bulge or herniation yet they experience little or no pain or other symptoms from it.
The majority of lumbar herniated discs are located to one or the other side. There may be multiple lumbar disc bulges at various levels and effecting both sides.
Occasionally a disc bulge can occur centrally. This can be very serious if it compresses on the spinal nerves within the spinal canal causing what is called a cauda equina syndrome. This term "cauda equina" is latin for horse tail. It is used because the bundle of nerve fibers in the lower spine have the appearance of a horse tail.
Interestingly, the disc will usually rupture after heavy lifting or
lifting with your back especially when it involves a twisting and turning motion. This is because the internal pressure of your disc will go from 17 PSI (pounds per square inch) while lying down to 300 PSI with bending at the waist when your spine is not in a neutral position.
A healthy disc and proper body mechanics, with your spine in a neutral position, should withstand normal pressure changes within a disc.
An unhealthy disc due to injury, poor nutrition and chronic wear and tear will not be able to withstand even normal pressure let alone an increase in pressure.
The majority of lumbar disc herniations occur at the L4-L5 and L5-S1
discs. The "L" refers to the lumbar and the "S" to the sacrum. Whereas, the number refers to the specific vertebra.
So, when a L5-S1 herniated disc is mentioned it is referring to the disc lying between the L5 vertebra and the sacrum.
What are most of the factors that contribute to poor disc integrity and eventually a herniated disc?
A lumbar disc bulge or lumbar herniation is either discovered by means of an MRI, CT scan or lumbar mylogram.
Because of the quality of MRI and safety mylograms are no longer used.The MRI is the preferred imaging that is utilized today. It is non-invasive, safe and produces very sharp and accurate images.