An Intervertebral Disc is made up of two primary components. The first is the outer layer of fibers known as the annulus fibrosus. Think of this as the ‘dough’ in a jelly doughnut. The second portion is the inner material known as the nucleus polposus which can be compared to the ‘jelly’ portion of the doughnut. The nucleus of the disc acts as a shock absorber, and a fulcrum, absorbing the impact of the body’s daily activities and keeping the two vertebrae separated.
To learn more about how the disc does this think of that jelly doughnut. Now, I want you to imagine what would happen to the jelly if you put some pressure on the front end of the doughnut. The jelly would migrate or move towards the back. The opposite would occur if you put pressure on the back portion of the doughnut. The disc functions in a similar manner and acts as a fulcrum upon which movement can occur. When one develops a prolapsed disc the jelly/ nucleus pulposis is forced out of the doughnut/ disc and may put pressure on the nerve located near the disc. This will give one the symptoms of sciatica or a corresponding radiculopathy (numbness/tingling/shooting pain/etc.).
The nucleus of the disc will begin to dry out as we age and this will hinder it’s ability to absorb shock properly. Along with a weakening annular fiber, with age, we see more frequent tears which result from repetivie stress to the weakened tissues. This causes pain for some, but not in all cases.
In Medicine one generally refers to the gradual dehydration of the nucleus pulposus as degenerative disc disease or if accompanied by bony changes; spondylosis.
When the annular fibers tear as a result of aging or injury to the area, the nucleus can begin to migrate through the tear. This is known as a herniated nucleus pulposus. Near the back side of each disc are major spinal nerves that extend outward t the organs, tissues, extremities and other body parts they control and innervate. It is quite common for the herniated disc to press against these nerves and cause pain, numbness or tingling down the affected area often termed a ‘pinched nerve’. Also worth noting is the fact that the inner jelly material is very inflammatory and so whatever it comes in contact with will likely become inflamed and cause significant pain. If the pain is nerve related it is generally referred to as radicular pain.
Disc can become slipped, ruptured, or bulged. However, in medical terms it is more commonly referred to as:
2. Extruded Disc
3. Sequestered Disc
Up until a few years ago surgery was the only option for those who failed therapy. A gap between these two groups left no other options for those who failed therapy. Soon you will learn about a new option that bridges the gap between failed therapy and surgery.
Surgery should be considered if a patient has a significant neurological deficit, or if they fail non-surgical therapy. The presence of cauda equina syndrome (in which there is incontinence, weakness and genital numbness) is considered a medical emergency requiring immediate attention and possibly surgical decompression.
The Cochrane Collaboration, after a meta-analysis or randomized controlled trials, concluded that “limited evidence is now available to support some aspects of surgical practice.” Indications for surgery have been refined as a result of these findings and additional controlled trials.
Only after all other means have been exhausted should surgery be considered as an option.