The Meninges: another misunderstood and distorted cookieRicerca e scienza
di Maximilien Girardin
We catch the pony back where we stopped with the cranial question 4 … I think was missing… (https://www.linkedin.com/pulse/cranial-bones-sutures-fascia-another-popular-demand-max-girardin/)
En route! as goes the song from Tourist le MC, hiphop from Antwerp in dialect…medieval music ambiance perfect for a dinosaur while writing in a ferocious stream of consciousness and as usual puffing my pipe along like a steam-train ….
4 was…let’s have a look:
4. or why do we have so many layers of fascia, some attached to the bone and some not like some the ones covering the central nervous system: Dura mater parietalis, dura mater visceralis, arachnoidea parietalis arachnoidea visceralis, and pia mater ? Or are they not so free as usually perceived?
The head picture is a give away, of course they are not free as some popular ‘nonsense models’ suggest…worse they are not even adherences as Parke & Watanabe falsely stated in 1985 in a scientific article for which they even got the “Volvo Award” or something like that…if my memory is not failing me…
Models, models, models, go to Legoland with your models, there they are in the exact right Space-Time, not in practicing osteopaths’heads.
Normal means according to the norm…
The big average of what is accepted and used…
The more we have grown used to models, the more they have become the norm and are consequently being accepted as NORMAL.
As said in the early sixties”Le Grand Jacques ” Brel in his song ‘le caporal casse-ponpons’ CONSEQUAMMENT…(Consequently in English)
“There is a difference between natural and normal and yet we’ve innocently mistaken one for the other and that they are the same thing…”
I quote an English speaking clear thinking man here but forgot his name, sorry mate? In my Pidgin English I would have been in the impossibility to formulate it in such a concise and perfect way…excuse an old fool for forgetting your name brother. If you ever read this and reveal your self, I will gladly edit this and add your name just wise.
But they are not, hence the rearguard fight that some of us are doing…And clearly we won’t win the battle, it is against all odds, but ‘standing our ground’ is the only thing we can do. “Persiste et signe” sincerely yours: en route for real now.
I hope you remember that the developing future spine is just a connective lump of tissue surrounding the explosively growing central nervous system, hence being stretched to an almost unbearable rate…Remember? the blue and red arrows in the embryo represent the two major forces at work in a dimension of the whole…
As said the whole is a long story of a process.
So this, at an explosive rate growing nervous system, is the relative stretching and thus one of the instigating growth motors for the connective surrounding lump. That scene being set, there is a huge difference of environment for that lump of connective tissue decentered in its core is the nervous system while on the front side is the whole circulatory vascular and lymphatic trunk (what we tend to call affectionately the ‘Homunculus Internii’) and more upfront (anterior) sticking to it the Visceral package (Homunculus Viscerocranii) which is even more sluggish in his growth rate than the two homunculi in his back.
The result (extremely simplified in this dimension) is a series of shear forces at play between three ‘relative’ subparts of the whole organism in growth. On of the main visible results in the microscope is that the whole organism (embryo) is a general curving or flexing towards the most sluggish growth region: the Homunclus Viscerocranii. This process changes the whole situation within our lump of connective tissue (the future spine). Although the Homunculus Internii is playing a crucial role with his circulatory development here, we’ll drop him for now, this format handicaps me on a drawing level and we were focussing on the meninges… so let us zoom in and look at what happens in the core of the connective lump.
The more it curves the higher the shear forces in different directions, the main restriction apparatus that we can use as constant now is the Homunculus Internii on the front (wrongly simplified but enough for the focus purpose of this article) Extreme simplification: The nervous system continues its galloping growth and the Vascular package resists as it can’t follow that speed of growth, keep that image in mind and then focus within connective the lump-future spine and content. ( It is a process so make it a movie in your head, a living picture)
On the inside the rips are longitudinal, the dura mater is ripped in two longitudinally the parietal part (if we may call it as such) will become a part of your Flavum system, the visceral part is ripped completely loose and is what we call the dura mater spinalis today although in reality and continuity it is actually just the dura mater visceralis, as the morphologists – anatomists knew before the big simplification waves…
The backpart (posterior) of the lump is submitted to the biggest pull strains and changes its nature (texture in consequence) the same in compression strains on the front ( it starts slowly to shift towards cartilage and much later even in bone) As the backpart starts to rip to pieces or show fissures we see the from back to front: horizontal rips that are the future arci vertebrales , and even more or less vertical fissuring or rips that will later develop and form the pedunculi and vertebral articular facets… yes the fast galloping CNS and restrictive aorta (simplified) are the main actors in the formation of the primitive articular facets…think Golden triangle also for articular spine strains…
( Hierarchy ad Chronology)
Some connections between both stay but they lok in an adult as minute like a spiderweb structures that mostly stabilizes the whole complex vascular system ( Souillé described them as trousseaux fibreux)
The spiderweb like structure in between the two nerve roots, visible where the pincet lifts the dura mater spinalis are the Trousseaux Fibreux de Souillé, normally they are all over the place but when the spinal canal is opened this way they get destroyed in the process.
More on the front the separation between the Dura Mater parietalis and visceralis will happen too but much later and less decisively they will maintain stronger bonds a bit like the Sharpey’s fibers in the cranial sutures, but here they will get different names: Trolard’s ligamentum Sacrodurale which despite its name is present all along the spine, The ligamenta dorsolateralia or Hoffmann’s ligaments that rest-connection between the ligamentum longitudinalis posterius (parietal Dura Mater) and Dura Mater (Visceralis) and covering of the radices spinales.
Do you realize what is the consequence of this? The actual anatomical terminology is biased, distorted and partially erased… Actually suffering from selective blindness.
The today called epidural venous system is continuous with the intracranial sinuses … meaning they are not epi – but intradural…
Classic (today anatomy books) tell you the dura is bilayered in the cranium and single layered in the spine??????????????????????????
One layer disappears around the foramen magnum, probably Harry Potter or one of his companions passed there around in the neighborhood and said something like “disappear-iamus” waving his want? Come on, really?
All respect for J.K.Rowling I really think she is a hot magnificent lady but that anatomists and their sacro-saint ‘Nomina Anatomica’ got seduced to that point …REALLY? Am I in LALA LAND OR WHAT?
In full respect in my country and dictionary this is called having sh.t in the eyes…or worse only recognizing what you know…hear ‘have learned’ like : “Polly says, good morning or Hello” we are deep in it… how deep do you start realizing that?
That makes me think of a classic countryside joke from where I live (changes of the song lyrics doesn’t it?) :
A little bird lies freezing and almost dying on the early winter meadow, a cow sees it and soft hearted as these animals usually are, craps on it…a big flat covering cows pancake, nicely hot. A cat passes by sees the birds head sticking out and picks it out between two sharp nails and snaps the bird and shakes it vigorously to get it +- clean and eats it. What are the morals of this tale? Not every body that craps on you is malvolent, and not everyone that drags you out of the crap is well willing for your health!
So, where do we stand?
Look for yourself don’t believe me nor anyone on social media… The following picture is of a human embryo….
VB is the vertebral body in development, still in cartilaginous condition by the look of the cells, although on the top it may be shifting towards osteoclasts in the little denser dot ( less intercellular matrix) EDM is the external Dura Mater …see it splitting between visceral and parietal on the sides? MS is evidently the Medulla Spinalis in growth spurt, white matter on the external part and cells or gray matter in the centers…with the developing artery in between the two bulges…and the Pia Mater ac-colated to it. NON DE DIEU Max why do you give it away too soon?
Effectively that is what I just did, DAMNED
The Pia Mater and Arachnoid are also the layers that are slowly ripped away from the connective layer…..and fluid produced by the neurons and vessels fills it up….. Crap!
Just put you before a tough choice… believe your own eyes, logic and reason or go “Polly says Hello” that is written in most modern anatomy books today…
What you decide is your thing not mine…my reference frame is Nature and FORM, what yours is I don’t know? Sorry dear reader to maybe have just pulled some legs from under your chair you where sitting on. I did not mean any harm to your coccyx or pelvis….sincerely.
Talking about coccyx that is an even more funny one, ha ha ha ha,
As an embryo your medulla is down under (like Aussies) at the end of your sacrum, as is the Dura Mater visceralis but by the speed of growth at one point of the connective lump (spine) catching up the growth of the CNS, and surpassing it like crazy…The Dura visceralis gets ripped away from its parietal part and travels upwards…to end in most adults around S2 or 3 and stay fixed there by the famous ligamentum sacroduralis Anterius of Trolard. While the Conus Medullaris is staying where it was since the beginning if you take the organism as a whole (region L1 / 2) but the spine goes on growing away from it…. ( the image below is from a human fetus of +- 10 cm, in the sacral canal….think and reason…if you really don’t get out of it contact me and I’ll give you a full topo…for now use your brain)
A bit confusing while we are used to handle different frames of reference …and as such you hear or read nonsense as the upward movement of the kidneys, the one layer of the Dura Mater Spinalis and being bilayered in the cranium…. and so on but I already mentioned that in other articles…
Who said that in the land of crazy the mentally healthy or the one reasoning is a fool or something similar? Why did that pop up in my mind? I wonder?…… Life in an organized civilized society is a strange thing, isn’t it? I wonder?
Time to smoke another pipe…. CHEERS