Chronic Pain Part 1

“Something has to be torn.” Your back hurts or maybe its your shoulder or a knee and you go see a Physical therapist, a chiro, an ortho or even your primary care and you will hear the same thing. The details will differ from provider to provider but they will almost surely tell you that if something hurts you have a structural problem.

 Maybe it’s your posture or it’s your pelvis out of place or your back is out of alignment or maybe you have overactive muscles. It has a million different names but they all boil down to there is something wrong with your alignment or the structure of your body and this is why you have pain.

On the surface this makes absolute sense. We think of bodies as machines so if you are getting a pain signal it has to be because something is wrong with the machine. The body as a machine though is a terrible analogy. The body is much more complex. It isn’t a piece of furniture. The truth is most of us have postures that differ from ideal, although no one seems to agree on what bad posture is. Sure, you may think you have bad posture but look around. You aren’t abnormal.

Almost everyone has a leg length discrepancy. (1) 85 percent of men and 75 percent of women have an anterior pelvic tilt and another 6 and 7 percent had posterior pelvic tilt. (2)  No one is normal as we define it but the reasons these things seem to be related to pain is we don’t look at them until there is a problem.

 I had a conversation with a friend who is a peripheral nerve surgeon. She explained that a lot of the upper extremity nerve problems she sees are caused by bad posture. I asked her to describe then look around the Starbucks. Sure enough all the things that we common in cubital and carpal tunnel were also super common in the normal population.

Study after study has looked a postural and structural abnormalities and can’t find a connection. Pain appears to be less about actual injury and more about sensitization.

“structural factors such as the size of the lumbar lordosis, pelvic tilt, leg length discrepancy, and the length of abdominal, hamstring, and iliopsoas muscles are not associated with the occurrence of LBP.” (3)

The truth is most back pain and pain in general doesn’t have a structural cause., over 95%. But what about when the things we are sure are structural issues like ?

So you have degenerative disc disease or maybe you had an annular tear and you were told that is why you have pain and you should expect more of the same. That is a big nope. Neither one of those or even something like stenosis is closely correlated with pain.

What does that mean? It means that while you may have a tear or stenosis so do a lot of people with absolutely zero back pain. Things like annular tears, (56%) (4), Lumbar spinal stenois (77.9%). (5) Even in the most sever stenosis only about 17.5% had symptoms. This supports research that says stenosis alone cannot cause back pain.

What about the ultimate back problem everyone fears, the herniated disc. Turns out they are common and very commonly come without back pain. 35% of people without back pain between ages 20 and 39 had at least one degenerative or bulging disc and almost everyone over 60 did. (6) zIt was previously believed that nerve root compression was required to have pain and radicular symptoms but even that now isn’t seen as sufficient. (7) (8) (9)There is evidence that inflammatory mediators are required.

But It’s my shoulder

The back is the most well studied because it is the leading cause of disability worldwide but it is by no means special. The rotator cuff of the shoulder takes a lot of the blame for shoulder pain, but the severity of the tear isn’t associated with pain (10). Even more interesting is that rotator cuff tears in people without any shoulder pain are common. (11)What is even more confusing is that it is common for a patient being treated for a painful rotator cuff on one shoulder may have a tear on the other that causes no pain (11)

Your knee pain isn’t different. Often blamed on things like tight IT band, knee pain like back pain usually isn’t structural. In one study female athletes were tested before the season for “tight” It bands and while zero were discovered it was the IT band syndrome was the most common injury on the team. (13)The second was that kneecap pain a lot of runners are familiar with called patellofemoral pain syndrome. That too isn’t structural as it isn’t associated with damage, weakness or tissue degeneration (14) (15)

Just like the back and shoulder structural issues don’t correlate well with pain. Sensitivity to pain not severity of arthritis was a predictor of pain in osteoarthritis. (16)A torn meniscus is exceedingly common as we age and is almost always asymptomatic. (17)

Surgery vs Fake Surgery

When it comes to these structural issues surgery is often the recommendation even when we know the pain may not be directly related. (18) Does surgery work? Sometimes yes but usually physical therapy is just as effective. (19) Now this may seem to favor PT but there is more to the story. Physical therapy has a broad range of techniques employed for similar injuries and one doesn’t seem to stand out. So is it the PT or a placebo? You can’t really fake PT but there you can fake surgery. One review found that sham surgery was effective in 74% of cases and ”(49%) trials, surgery was superior to placebo but the magnitude of the effect of the surgical intervention over that of the placebo was generally small. “

All of this underlines how complicated pain is and how unrelated to structure it actually is. In the short term getting relief things like PT seem reasonable. Getting treatment is a huge step in the right direction even if that treatment is a placebo. The one thing you don’t want to do is nothing. Just trying to make it better can help and doing exercises and getting massage is far less invasive then going under the knife. It’s important though to understand as improvement doesn’t mean great. To really deal with the issue, we need to deal with the underlying problem of inflammation.

More and more research is being done on the role of inflammation and pain or more accurately the immune system. Mediators like IL-6 have long been known to have a role in pathologic pain but more research has deepened our understanding. Things like low back pain appear to be associated to what is termed a lack of inflammation because of the higher-than-normal level of Tregs which are supposed to downregulate inflammation.

We need to first understand how the immune system can be involved in chronic pain so we will tackle this in part two.

After we understand how the immune system can play a role we need to learn how to control it. We do this through sleep, diet and mindset. In part three we will cover why and how these lifestyle factors play a role in the immune system and pain.

Works Cited

1. [Online] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1232860/.

2. [Online] https://pubmed.ncbi.nlm.nih.gov/21658988/.

3. [Online] https://pubmed.ncbi.nlm.nih.gov/12322811/.

4. [Online] https://pubmed.ncbi.nlm.nih.gov/9423651/.

5. [Online] https://pubmed.ncbi.nlm.nih.gov/23473979/.

6. [Online] https://pubmed.ncbi.nlm.nih.gov/2312537/.

7. [Online] https://pubmed.ncbi.nlm.nih.gov/17704089/.

8. [Online] https://pubmed.ncbi.nlm.nih.gov/32169419/.

9. [Online] https://pubmed.ncbi.nlm.nih.gov/9726337/.

10. [Online] https://pubmed.ncbi.nlm.nih.gov/24875019/.

11. [Online] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7026731/#:~:text=Asymptomatic%20rotator%20cuff%20tears%20(RCTs,pain%20or%20a%20symptomatic%20RCT..

12. [Online] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7026731/#:~:text=Asymptomatic%20rotator%20cuff%20tears%20(RCTs,pain%20or%20a%20symptomatic%20RCT..

13. [Online] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC522150/.

14. [Online] https://pubmed.ncbi.nlm.nih.gov/16848349/.

15. [Online] https://journals.lww.com/cjsportsmed/Citation/1993/07000/The_Myth,_Mystic,_and_frustration_of_Anterior_Knee.1.aspx.

16. [Online] https://pubmed.ncbi.nlm.nih.gov/22961435/.

17. [Online] https://link.springer.com/referenceworkentry/10.1007/978-3-642-36801-1_70-1.

18. [Online] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6539146/.

19. [Online] https://pubmed.ncbi.nlm.nih.gov/27385156/.

20. [Online] https://www.nejm.org/doi/full/10.1056/nejmoa1305189.

21. [Online] https://pubmed.ncbi.nlm.nih.gov/12110735/.

22. [Online] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1232860/.

22.