What’s causing your lower back pain ?

Okinawa Sports and Spinal research review

A great study was just published in the open source Spine Journal  that gives a great review of the current understanding of the role of disc degenerative and how changes in the disc structure might be causing your lower back pain.

If you do experience lower back you not alone. In 2020, 619 million people worldwide suffered from low back pain (LBP), nearly 10% of the global population, and this figure is expected to rise to 843 million by 2050 due to many factors. Low back pain is complex and it involves a lot of factors such as structural, chemical and also the role of how your nervous systems interprets the world around it.

Over the last few years a lot of research has focused on the Bio psycho social model highlighting just important the role of the nervous system is shaping our experience and showing that different people can respond very differently to pain. This has shed tremendous light on this and been a great improvement but their is risk that we can overlook the importance of structural changes too. The do matter.

The most common cause of chronic pain is changes in our spinal discs.

If you want to understand a spinal disc in the lower back think of a onion slice, and then pull out the inner 3rd of the layers and crack an egg in them. Now you have some concentric rings around the outside known as the Annulus Fibrosis (AF)  and a going Centre known as the Nucleus Polposus (NP )

There are lot more cells in the AP with around 9,000 cells per square mm whilst the NP is mainly fluid with around 3,000 cells per square mm. The role of the AF is resist stretching and prevent the gooey NP building too far and the role of the NP is to be the bodies ” shock absorber ” and absorb force and distribute it outwards.

Stages of spinal degeneration

As the disc is damaged it goes through 5 changes.

Basically as the disc degenerative changes go through stage 1 to stage 5 it starts to affect not the joint but the underlying bone around the joint plus interesting things start happening. As they pressure in a healthy disc stops this allows nerve and pain fibers to grow into places they should not usually be such as the inner rings of the fibers of the disc.

Once you get into grade 4 and 5 there is end plate ( the bone either side of the joint ) irregularities that causes an inflammatory response. So now we have a complex interplay between structural changes, changes in the inflammation and the growth of nerve fibers in places they do not necessarily belong as well the growing body of knowledge about perception and our psychological state affects our pain. 

References

1. Neuroinflammation and nociception in intervertebral disc degeneration: a review of precision medicine perspective

   Zàaba, Nurul Fariha et al.
   The Spine Journal, Volume 0, Issue 0

https://www.thespinejournalonline.com/article/S1529-9430(25)00008-7/fulltext