Updated: May 5
“I threw my back out” “I ruptured a disc” “I pinched a nerve”
I hear phrases like this all of the time. If you know me (or read my previous post on how to move better) then you know that I think we do a terrible job of messaging when it comes to back pain.
Up to 80% of people have back pain at some point in their lives and 1 in 5 have it every year.
These are huge numbers. If every person who had back pain “ruptured a disc” then we would not be able to function as a society. The first step in this conversation is acknowledging that you probably did not herniate a disc in your low back when you hurt yourself.
The next step is to realize that, even if imaging shows a herniated disc, then that is not necessarily your problem. This can be hard to grasp, as we are wired to equate an MRI with the absolute truth, but our bodies are more complicated than that. A study by Brinjikji, et al. found that disc bulges occur in 30% of people in their 20s who have no pain. That percentage increases to 84% of people in their 80s, once again with no pain. Also, disc degeneration, which is a term for any sort of wear and tear on the disc itself, was present in 37% of people in their 20s and 96% of people in their 80s with no pain. (1)
These numbers are staggering. If you are in your 20s and have no current back pain, but you went and got an MRI of your spine anyway, there is a 1 in 3 chance that you would have a disc bulge and/or degeneration. Imagine a physician giving you that news. It would be impossible not to become fixated on your back after receiving this information.
Now, let’s look at how we diagnose a herniated disc. To understand the testing mechanisms, it’s important to understand some basic anatomy.
The intervertebral discs are between the body of your spinal bones. Behind them are your nerves that run down your spinal canal. Behind those are your spinous processes, which are the part of your spine that you feel on your back.
Imagine bending forward to tie your shoes. The spine will flex forwards which creates pressure in the front due to compression. This forces the discs to move backwards from the force. In cases of herniation or bulging, the discs can press into the spinal canal behind them, or tear and secrete fluid or fragments into the canal.
There are nerves that innervate your discs themselves, which can be irritated with certain movements or loads. The typical “bulging disc” however involves pressure on the nerves in the spinal cord themselves. This can create pain at the disc, but also radiating down into your leg, as that is the pathway of those nerves.
So, now you know a little bit of anatomy. That is going to help you with understanding the diagnosis of a herniated disc. If you had to guess which motion would typically be painful with a herniated disc, you would hopefully guess flexing forward, based on what we discussed earlier. Rotation can also cause pressure on a herniated disc, and if you have the most pain with bending forward and rotating then this is a telltale sign of disc irritation. Often, the initial injury can be due to picking up something and twisting rapidly.
Another test we utilize to diagnose a herniated disc is a straight leg raise.
If it looks very similar to a hamstrings stretch, it’s because it is. What we are trying to accomplish, is to replicate your symptoms. I don’t care if your hamstrings are tight, or it hurts your calf to do this stretch. If you tell me that you back is hurting, then I want this test to replicate your back pain in the same location. If part of your symptoms are hamstrings pain, then this test should replicate those symptoms to be positive.
A negative straight leg raise does not necessarily rule out a herniated disc, but it is encouraging because it usually that means the nerves are unaffected.
Let’s say that you clearly remember lifting up a heavy box with a twisting motion, pain began immediately, days later it hurts to bend forward and rotate, and when you stretch your hamstrings it hurts your back. You should go see a medical professional, and I would honestly see a physical therapist first. You may be thinking “my disc is probably herniated, what can PT do at this point?”
One study involved a CT scan of 21 patients with a herniated disc and nerve root pain (pain going down the leg). All 21 had PT and recovered. 6 months later, they were all given a new CT scan and 14 of them had “a definite decrease in size” of the herniated disc. (2) That is pretty cool. 2 out of 3 patients had demonstrated evidence of their disc herniation decreasing in size 6 months after PT, and all of them felt better!
Another study looked at 370 patients who received conservative therapy (PT) or surgery in which the surgeon removed the portion of the disc that was herniated. The study showed that after 6 weeks, the surgical group had less pain, but at 1 or 2 years later, there was no significant difference between the groups. (3) This makes sense because it can take several weeks for discs to heal and gains to be made in physical therapy. It is encouraging that the long term outcomes are similar.
Now, this is not saying that surgery is never necessary, or that you should not do what you can to feel better and move better. I do believe that good quality physical therapy can help a majority of patients who have back pain, and also it can even help those who have a herniated disc confirmed by an MRI.
Over the next several days, I will post some exercise ideas and rationale that I have used in helping hundreds of patients recover from back pain and get back to doing what they love. Follow me on Instagram and Twitter @drdannydpt and maybe you will get some ideas!
Thanks for reading, and if you have any questions or comments please leave them below or email me at firstname.lastname@example.org
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1 Brinjikji, W., Luetmer, P. H., Comstock, B., Bresnahan, B. W., Chen, L. E., Deyo, R. A., ... & Jarvik, J. G. (2015). Systematic literature review of imaging features of spinal degeneration in asymptomatic populations. American Journal of Neuroradiology, 36(4), 811-816.
2 Delauche-Cavallier MC, Budet C, Laredo JD, et al. Lumbar disc herniation. Computed tomography scan changes after conservative treatment of nerve root compression. Spine. 1992 Aug;17(8):927-933. PMID: 1387974.
3 Gugliotta, M., da Costa, B. R., Dabis, E., Theiler, R., Jüni, P., Reichenbach, S., ... & Hasler, P. (2016). Surgical versus conservative treatment for lumbar disc herniation: a prospective cohort study. BMJ open, 6(12), e012938.