Posts

Dural Venous Sinuses

The RTM and Venous Sinuses

Dr. Robert Acland narrates a video illustrating the anatomy of the dural venous sinuses, and the related neurological and osteological structures. Particularly interesting to see the Cavernous Sinus in coronal cross-section at 5:40.

 

REFERENCES

Dr. Robert Acland,  ‘Acland’s Video Atlas of Human Anatomy Neuroanatomy’ YouTube standard license https://aclandanatomy.com/

Tensegrity Structure Icosahedron

How Does The Cranial Vault Retain Stability During Growth? – ‘Tensegrity’ has the answers

Continuing our look at the function of the dural membranes and RTM, researcher and Osteopath Graham Scarr’s paper ‘A model of the cranial vault as a tensegrity structure, and its significance to normal and abnormal cranial development’ proposes a novel understanding of the integrated and dynamic relationship of the bones and membranes.

This model helps to explain how the skull vault bones maintain sutural patency, while preventing early fusion (cranio-synostosis):

“Tensional forces in the dura mater [and suture] have the effect of pushing the bones apart, whilst at the same time integrating them into a single functional unit …Cells of the dura mater respond to brain expansion and influence bone growth, allowing the cranium to match the spatial requirements of the developing brain, whilst remaining one step ahead and retaining a certain amount of autonomy.”

Scarr also alludes to the possibility that the development of positional plagiocephaly may be explained by this model. Seeing as at seven weeks old the prevalence of positional plagiocephaly may be as high as 22% understanding this model is highly relevant to practice.

If this is the first time you’ve come across the concept of tensegrity, Tom Myers, author of Anatomy Trains explains the basics of how the human body is not a compression structure like a building, it is far more dynamic.


Our upcoming 5-day course provides more information on the anatomy and function of the Reciprocal Tension Membrane, and it’s integration within the OCF concept


References:

A model of the cranial vault as a tensegrity structure, and its significance to normal and abnormal cranial development
Scarr, Graham
International Journal of Osteopathic Medicine , Volume 11 , Issue 3 , 80 – 89
http://www.journalofosteopathicmedicine.com/article/S1746-0689(08)00032-1/abstract

 

Prevalence, risk factors, and natural history of positional plagiocephaly: a systematic review.
Bialocerkowski AE1Vladusic SLWei Ng C.
Dev Med Child Neurol. 2008 Aug;50(8):577-86. doi: 10.1111/j.1469-8749.2008.03029.x.

 

Tensegrity Icosahedron Picture

By Bob Burkhardt [CC-BY-2.5], via Wikimedia Commons

 

intracranial dural membranes side view showing falx and tentorium

We Have Got You Covered – how the meninges control brain development

Meningeal layers

A little revision of the meningeal and periosteal layers of the brain and skull

As osteopaths working with OCF, we are already aware of the importance of  the ‘reciprocal tension membrane‘ as Sutherland referred to it.

However, according to this research from 2011, the meninges also seem to have an important role in foetal brain development:

“Through the release of diffusible factors, the meninges influence the proliferative and migratory behaviour of neural progenitors and neurons in the forebrain and hindbrain. Meningeal cells also secrete and organize the pial basement membrane, a critical anchor point for the radially-oriented fibers of neuroepithelial stem cells”.

Seeing as much brain development occurs in the first year of life outside the womb, it seems possible that brain development could be affected by continuing deformity or strain within the membrane system, left over from the birth/perinatal process (study anyone?). The authors conclude with this:

“It is also clear that disruption of meningeal function either generally or focally can lead to significant disruption of (foetal) brain development. Future work will inevitably expand our understanding of the human syndromes where brain malformations are caused primarily by defects in meningeal development”.

Check out the PDF below for the full text.

PDF: we have got you covered – how the meninges control brain development

 

Our upcoming 5-day course provides more information on the anatomy and function of the Reciprocal Tension Membrane, and it’s integration within the OCF concept

 

References:
“We’ve got you “covered”: how the meninges control brain development”
Julie A. Siegenthaler and Samuel J. Pleasure
Curr Opin Genet Dev. 2011 June ; 21(3): 249–255. doi:10.1016/j.gde.2010.12.005.

‘Meninges’ image By SVG by Mysid, original by SEER Development Team [1] [Public domain], via Wikimedia Commons