The degenerative process of the intervertebral disc is one of the most productive ítems in basic science research of spine pathology as it is the key to one of the most frequent causes of physician consultation: cervicalgia/lumbalgia.
In the early years of this century, experts told that the way was long and that ten to fifteen years were needed to have something applicable to clinic. Almost twenty years after no such effective proven treatment has been reached, although there is plenty of information on biochemical markers, cell cultures, animal models and research on these,… but they all end up with some comment about the translation to human clinics to be cautiously taken into account. But this is no frustration message, on the contrary, we now know much more about it: apoptosis, nutritional deprivation, disc cell types, body response to the process… and it is at this point where this paper [Citation1] focuses.
The authors tell us there are an enzymatic milieu at the disc that fosters vascular ingrowth, crashing down the “avascular, anneural” histology of healthy discs; or perhaps we should stop talking about healthy and think of a process guided by genetic factors at most [Citation2,Citation3], encased into the apoptotic/regeneration process of biological tissues, profoundly based on nutritional deprivation –as we published [Citation4]- of an scarce population of a highly specialized cells that control homeostasis of disc tissue, originating a cascade of events at biochemical level [Citation5–7] and, then, a vicious circle at histological level [Citation8] with a correlation at radiological level (Pfirmann grading scale, Modic changes), which, in turn, has got some clinical meaniing.
The authors correlate pleiotropically the destruction of disc matrix (aminopeptidase N and leucine aminopeptidasde) with enhancement of a vascular response by the inflammatory response of the epidural space to its violation by disc tissue; so it is kind of “foreign body reaction” happening at the epidural space that brings about the healing of the herniated disc.
This understanding of the degenerative process of the intervertebral disc helps planning the management of individual patients, also giving a background for therapies such as epidural injections, for instance. Modulation of the defensive response of the body to a disc disruption, with sudden outing of disc material to where it should not be, sets the basis for nonsurgical treatmentof disc herniation.
Another topic for discussion beyond these results is that I am not certainly sure that disc herniation and disc degeneration be the same, in actual fact I think probably they are not.
Declaration of interest
I, Máximo-Alberto Díez-Ulloa has neither any comercial interest nor any disclosure to make related to my submission to Journal of INvstigative Surgery entitled “Role of microangiogenesis in the healing of disc herniation” submitted as a comment to paper UIVS-2019-0515.
References
- Correlation between proteolytic enzymes and microangiogenesis in degenerative intervertebral disc nucleus. J Invest Surg. doi:10.1080/08941939.2019.1679921.
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- Fernández-Susavila H, Pardo-Seco JP, Iglesias-Rey R, Sobrino T, Campos F, Díez-Ulloa MA. Model of disc degeneration in rat tail induced through vascular isiolation of vertebral endplates. J Invest Surg. 2018;31(4):265–274. doi:10.1080/08941939.2017.1317373.
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