A common experience for someone with an episode of low back pain is to go to the doctor’s office for imaging, with the thought that there is something structurally wrong with the spine that can be fixed. The imaging report often comes back with a diagnosis of a "damaged" spine such as degenerative disc disease, disc bulge, disc protrusion, disc herniation, and facet degeneration. Although 90 percent of individuals with low back pain have a disc herniation, it may not be the cause of your low back pain. This post will discuss how the "damaged" spine diagnosis does not correlate to low back pain and what other treatment strategies should be explored.
Let’s begin with some basic spinal anatomy. There are four basic aspects of the spine: vertebra, intervertebral discs, ligaments, and muscles.
The vertebral bones are specialized in the spine to protect the spinal cord and provide weight-bearing support. Each vertebra has several parts that have different functions. The big oval portion is called the vertebral body and provides support for the weight of your body. There are bony projections that go up and down, which are called facets. The facets allow you to move your spine in various directions. The final part is the spinous process, which sticks straight out and is used as an attachment for muscles (you can feel them on your own back).
The disc is made of three major components: the nucleus pulposus, annulus fibrosis, and the end plates. The nucleus pulposus is a jelly like substance found near the middle of the disc. The annulus fibrosis are rings of collagen oriented in alternating criss-crossing patterns. The nucleus and annulus together provide weight bearing support to the spine. The end plate separates the nucleus pulposus and the annulus fibrosis from the adjacent vertebra.
So what does it mean if you have a damaged spine and can it be reversed? Here is a short and simplistic definition of the “damaged” spine diagnoses from above.
Degenerative disc disease - the size of the disc between the vertebra has decreased.
Disc bulge - the annulus fibrosis is pushing out towards the spinal canal.
Disc protrusion - parts of the nucleus pulposus are leaking past the annulus fibrosis.
Disc herniation - same as disc protrusion.
Facet degeneration - the spacing between the two facet joints is decreased.
Some of these conditions are reversible while some are not. Degenerative disc disease and facet degeneration are not reversible while disc bulges and herniation can go away with time, but it can depend on the size of the herniation.
So if you have one of these conditions, will you always be in pain?
Fortunately, the structural model of low back pain is outdated. Many times these structural issues are incidental findings. Because the development of these degenerative disorders takes a long time, the brain does not interpret them as a threat, and therefore, they do not cause pain. With that being said, there are some circumstances where these disorders can cause pain, however, these situations are rare in occurrence.
A study in the American Journal of Neuroradiology reported on the findings of degeneration in asymptomatic individuals. Their 2014 study revealed:
- Disc degeneration was present in 37 percent of 20 year olds and increased to 96 percent of 80 year olds.
- Disc bulges were present in 30 percent of 20 year olds and increased to 84 percent of 80 year olds.
- Facet degeneration was present in 4 percent of 20 year olds and increased to 83 percent of 80 year olds.
The conclusion to their study was “these findings suggest that many imaging-based degenerative features may be part of the normal aging and unassociated with low back pain.”
There is a possibility that you could have any of the above conditions right now and not even know it. For example, in chiropractic college I had an X-ray of my spine and found out that I had a spondylolithesis (the vertebra has moved forward compared to the one below it) at my fifth lumbar vertebra. I had no idea it was there. So just because these conditions exist does not necessarily mean that you are doomed to a lifetime of pain.
The problem with the overemphasis on structural diagnoses for low back pain is that it implies that pain will not subside without medical intervention, which is not always true. In fact, patients who have X-rays taken have reported longer duration and increased pain severity. While it is important to identify when imaging is necessary, a majority of the time there is no structural pathology linked to low back pain.
The biopscyhosocial model is the current model for the treatment of low back pain. It takes into account many other factors that can contribute to low back pain besides structural causes. For example, the brain can become hypersensitive to the environment and different movements to protect you from further danger. Gradual exposure to these activities can allow the brain to realize you are not in danger. Pain has also been shown to alter how you move, which is good for avoiding further harm in the short term but can have long term consequences. A movement assessment such as a the Functional Movement Screen or Selective Functional Movement Assessment can identify these altered patterns and key in on ways to fix them.
In summary, degenerative disorders of the spine are most likely part of normal aging and do not correlate with low back back. Although degenerative disorders can cause low back pain, it is more of a rare occurrence than once thought. A less than attractive X-ray or MRI does not mean that you have to suffer from low back pain forever. A comprehensive approach to the treatment of low back pain can help put you on the right track to recovery.
W. Brinjikji, Systematic Literature Review of Imaging Features of Spinal Degeneration in Asymptomatic Populations. AJNR Am. J. Neuroradiol. 2014.