What Actually Causes Disc Related Back Pain?
December 03, 2018
What causes disc pain?
Back pain is a very common issue in today's society and is the second leading cause of disability in the U.S. There are a handful of common causes for low back pain, one of them being disc pain. Having a bulging disc can sound scary and ambiguous. However, understanding exactly what it is can decrease the anxiety surrounding of this diagnosis and help you along the road to recovery.
The anatomy of a disc.
The spine is what gives our body stability and shock absorption for all daily activities. The most important 'cushions' in our backs are the intervertebral discs, which literally means "between the vertebrae." There are 23 of these discs and they go between every movable vertebrae in the spine. A disc resembles a jelly donut with a tough outer connective tissue to keep its semi-rigid shape and an inner viscous fluid for optimal shock absorbency. These tissues are flexible and made to accommodate and adjust to different movements the body will complete (bending, extending, etc.). For example, this means that as the body flexes forward because you want to touch your toes, the fluid of the disc will shift back to allow the front of the vertebrae to get closer together. (For a visual of this, look here.) Without this flexibility, it would be hard to move the way we want!
What symptoms occur with pathology.
When the connective tissue of a disc gets weak in one area (either from overuse or a sudden injury), this area can begin to bulge. You can imagine a squishy stress ball that gets weak in one area so that when you squeeze it all the fluid wants to try to push toward that spot of least resistance. In the spine, this will make it more difficult for the fluid inside the disc to do its cushioning job. This bulge can also go into spaces of the spine its not meant to be. This can put pressure directly on the spinal cord or its nerve roots and cause predictable symptoms (depending on which level of the spine it happens) related to pain, muscle guarding, shooting pain, and numbness.
What is the actual pain mechanism of a bulging disc.
The most common direction that a disc will bulge is backward and sideways (right where nerves enter and exit the spinal cord!). These tissues tend to get gradually weakened from being in a forward bent position too often, such as happens with excessive sitting or lifting. This leads to direct pressure on sensitive neural tissues and sends an "ouch" signal to the brain. This signal will then initiate the body's natural process of healing, starting an inflammatory process that will bring extra blood and oxygen to the area. The pain will also typically signal the body to tighten certain muscle groups (known as muscle guarding) to encourage you to rest and protect the back while the area heals. These are all good things in the short term, as long as they don't continue past 6 weeks when the issue becomes "chronic."
What can you do about it?
With flexion biased movement (bending) usually being the root cause of back pain from a disc bulge, it makes sense that spending time OUT of the bent position would be helpful. This means spending more time in a neutral spine, the way the spine naturally rests, to optimize spine alignment. A simple solution is spending some time during the day out of a seated position by lying flat or standing (if you can tolerate it). Since lying flat might not be productive for work and other daily activities, being able to work at a standing desk or taking frequent standing breaks (preferably every hour) may be very helpful. Additionally, as long as you aren't too sore and inflamed, it should also feel really good to spend some time with the back actually extended. There are some basic extension biased back exercises specifically for the back known as McKenzie exercises (check them out for some simple efficient postures to try). Lastly, there are a lot of lifestyle factors involved in back pain as well, such as diet, hydration, sleep and stress management. For more information, check out this helpful article.
If your pain is worse with sitting and bending motions and better with extended or standing postures chances are you are experiencing a bulging disc. If you feel confident you can try all the above mentioned techniques and see how it goes. If you're unsure or experiencing severe pain or any other red flags, its always important to consult your doctor.
Feeling informed can relieve some stress and help you on the road to recovery. Knowing what the problem is and what to expect can be half the battle to recovery. The good news is that with the right treatment and knowledge that most disc injuries will heal without any invasive treatments, whether it is independently or with the help of a trusted medical professional such as an orthopedist, physical therapist, or chiropractor.