Goal of the Study?
Learning how back pain develops and potentially advances in degenerative disc disease is critical. Back pain has profound socioeconomic costs worldwide. In this research paper1 a group of researchers looked to learn more about the anatomical details of the disc by looking at cell clusters rather than looking at the disc as a whole. Their goal was to investigate cell clusters (small, medium and large) to explore these cell micro-populations in the context of aging and repair.
Why are they doing this study?
Adverse loading of intervertebral disc cells can speed up degeneration and lead to back pain.2 These critical load-bearing structures are viscoelastic in nature and work to keep vertebrae separated from one another. Discs have three parts: a nucleus, an annulus and the hyaline cartilaginous endplates that sandwich the contents in place. Each of these parts can become deranged; however, we also see intrinsic repair strategies of the nucleus cells, for example.3 What if early degeneration can be offset with this new understanding of repair? Could we help prevent back pain by learning more about the clusters of cells and what kind of loading environment is optimal?
Human disc tissue from 55 patients was ethically used, undergoing spinal surgery. In addition, 20 rat discs were mechanically loaded along with an unloaded control. Each disc was divided into two halves, and one half was frozen to help cut. The tissues were stained to help create contrast under a microscope. A statistical evaluation using spearman’s rank was used to examine the differences.
What did they find?
The repair was stalled with abnormal complex loading of the disc cells. These researchers found early degeneration includes cell clustering and cannot cope with the inflammation and catabolic expression in the group with sustained physical disruption to get into an anabolic, reparative process.
Why do these findings matter?
Learning when and how to load a reactive inflammatory and histologically damaged disc can help manage low back pain related to degenerative discs. Over the years of back pain research, much effort has been put into the management of keeping people active. However, the next question will be what is too much and not enough for different low back pain people. Best rest is currently discouraged; however, overloading is also discouraged. Learning the different phenotypes and how to load manage each case will help the most in back pain.
- Cell clustering in intervertebral disc degeneration: An attempted repair mechanism aborted via apoptosis? ↩
- Adams, M. A., B. J. Freeman, H. P. Morrison, I. W. Nelson, and P. Dolan. 2000. “Mechanical initiation of intervertebral disc degeneration.” Spine (Phila Pa 1976) 25 (13): 1625-36. ↩
- Lyu, F. J., K. M. Cheung, Z. Zheng, H. Wang, D. Sakai, and V. Y. Leung. 2019. “IVD progenitor cells: a new horizon for understanding disc homeostasis and repair.” Nat Rev Rheumatol 15 (2): 102-112. ↩