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bi wiki skull dasein split bi wiki skull dasein split left vomer bi wiki skull dasein split right fused sbj bi wiki skull dasein lateral inferior

I have just uploaded some photos of a real skull. The skull lives at the Da Sein Institut near Zurich.

It has been split in half, so you get some great views of the facial complex, the fused sphenobasiliar junction (thats not moving anytime soon) and the vomer

You can see all the images, and much more, here:

myodural bridge

Myodural Bridge, Enix DE et al 2014 J Can Chiropr Assoc 58: 184

Myodural Bridges

This is a great review of connections between the sub occipital muscles and the cervical dura. There are some more images in the article. Here is David Butler discussing the anatomy:

The Myodural Bridge
‘What a name! I was always intrigued by the difference between a group of patients who could quite easily elongate their upper cervical extensor muscles (“pull your chin in”) and another group where upper cervical flexion was particularly sensitive and easily evoked headache. The repeated clinical anecdote is that the second group can flex their upper cervical spines more easily in sitting or even better, in supine with their knees flexed. This may well unload the myodural bridge.
Myodural bridges are connections between the cervical dura mater and the cervical extensor muscles. These connections probably anchor the dura and stop it folding in on the cord when you look up and extend your head back (Hack et al 1995, Rutten et al. 1997). This may have been an evolutionary advantage to our ancestors as they gazed up in awe at the firmament! There is a great recent review out by Enix et al (2014), updating the anatomy of the bridges including sub occipital bridges and proposing clinical implications. Think of it next time you are having a look at a patient’s posture as they sit in front of you with their worries and concerns? or ask someone to tuck their chin in. It also remind us that everything is kind of joined up in the body; discrete anatomy is for the textbooks.‘ David Butler NOI notes July 2014

Enix DE et al (2014) The cervical myodural bridge, a review of literature and clinical implications. J Can Chiropr Assoc 58: 184

Atlantoaxial Instability

Here is a good article on why it pays to be cautious in bodywork. I am so glad I do not introduce strong forces into the neck when I work. The biodynamic paradigm makes working with the upper neck and cranial base much safer. I was taught tests for vertebrobasilar insufficiency at chiropractic college but not that much about atlantoaxial instability.

‘Either atlantoaxial instability or vertebrobasilar insufficiency causes severe dizziness and vomiting after massage therapy, with lessons for health care consumers’

Famous welcome sign, Las Vegas, Nevada.

Research into the fabulous vagus nerve is a gift that keeps on giving. Activating the vagus supports people to be less depressed, enhances the immune system, including regulation of inflammation, and reduces pain. The first section is a summary from Dacher Keltner of some vagal highlights. The second section has some tips on working with the vagus from a biodynamic craniosacral therapy perspective.

How can you become a vagal superstar? How can you help your clients become vagal superstars?

Vagal superstars

The following are all features of the vagus according to Dacher Keltner (1), researcher and author of ‘Born to be Good’.

  • The vagus nerve is almost like an alternative spinal cord.
  • When you stimulate the vagus you improve people’s capacity to make decisions, this is true of the vagus nerve but not so much the spinal cord.
  • The vagus stimulates the release of oxytocin.
  • It optimises your heart rate. It evolved to support communication, social engagement and prosocial emotions such as compassion.
  • Nice touch to the back, you see a smiling face, (compassion towards) images of harm; these all cause the vagus nerve to fire. It gives specific stimulation to emotional processing centres. (Italics added)
  • ‘Vagal superstars’ demonstrate elevated base activity in vagal tone. Vagal superstars are more generous, more trusted, and kids with high vagal tone break up play ground fights.

Tips on applying the vagal brake: increasing vagal tone inhibits the sympathetics

Enhance vagal tone

  • Stimulating the new vagus (2) is the best way of switching of the sympathetics and supporting homeostasis (3), (4).
  • Be soft, slow and present.

Engage the extensors

  • Think of a monkey grabbing onto a tree trunk; all the muscles being used are flexors and are associated with sympathetics, stress and making ourselves small. The sympathetics are switched on when we contract into the fetal position.
  • We are in parasympathetic mode when we come into an upright posture with the extensors engaged. We feel safe enough to show our belly, heart and throat. We can engage with our environment, make ourselves big and move towards new things.
  • On the treatment table you can engage the extensors by getting your client to orient to the back of the body: ‘Can you feel the weight of your body on the table? Push your elbows and/or feet into the table.’

Engage the feet

  • Loss of the vagal brake results in a surge upwards as we orient; the head gets hot and tight, there is increased activity in the neck, cranium, heart, and lungs. We lose relationship to the bottom of the body and tend to disappear from our belly and our feet.
  • Grounding, being present and firing in parasympathetics nearly always involves engaging the lower half of the body and feeling the feet.
  • On the treatment table keep asking people if they can feel the size, shape and weight of their feet and their belly. Be persistent.


Go slow and embody vagal states

  • Words associated with the vagal activity are trust, love, compassion, acceptance, joy. Work to find these qualities in your own body as you treat. The clients body will mirror your state.
  • Think of a perfect lazy afternoon, full of a delicious dinner, in front of a warm fire, cosy in a chair, chatting with old friends……

Know the anatomy of the vagus and its ganglia

  • The vagus can be influenced by supporting change around the jugular foramen, the superior and inferior sensory ganglia below the jugular foramen, the carotid sheath, the larynx (4), the tragus of the ear, freedom in the breath and diaphragm, and resolving inertia in and around organs (especially the heart, lungs and sub diaphragm organs) to free up vagal motor ganglia and the enteric nervous system.
The Vagus. Left: The territory innervated by the paired vagus nerves above and below the diaphragm.     Right: Vagus nerves in black, and sympathetics in white, supply the heart and organs above the diaphragm.

The Vagus. Left: The territory innervated by the paired vagus nerves above and below the diaphragm.
Right: Vagus nerves in black, and sympathetics in white, supply the heart and organs above the diaphragm.

(1)  Keltner D. (2009) Born to Be Good: The Science of a Meaningful Life. 1st Ed, W. W. Norton & Company. See also Dacher Keltner in Conversation.

(2) The ‘new vagus’ refers to the mylinated vagus controlled by the ventral vagus complex (nucleus ambiguus) that co-ordinates oxygen control inline with muscles of facial expression. Porges, S. (2011) The Polyvagal Theory: Neurophysiological Foundations of Emotions, Attachment, Communication, and Self-Regulation. New York: Norton

(3) ‘The relative sympathetic activation seen in anxiety disorders may represent dis-inhibition due to faulty inhibitory mechanisms.’ The vagus inhibits the sympathetics.   – Thayer J. and Lane R. (2000) ‘A model of neurovisceral integration in emotion regulation and dysregulation.’ Journal of Affective Disorders 61, 201–216.

(4) ‘We propose that these findings have important implications for the understanding of the two-way communication between the heart and the brain, and provide a connection among negative emotions and negative health consequences via the common mechanism of autonomic imbalance and low parasympathetic activity.’  – Thayer J. and Ruiz-Padial E. (2006) Neurovisceral integration, emotions and health: An update. International Congress Series 1287 (2006) 122–127

(4) ‘The vagus nerve innervates the larynx’ it carries ‘general sensation, including pain, touch and temperature’ from the larynx. –  Laryngeal nerve anatomy: accessed Feb 2014.


Above is a fresh dissection showing a superior view of the cranial base with the dural lining intact, tentorium removed. The image is taken from here. You can see the olfactory and optic nerves passing through the dura. Fabulous. How shiny is the fascia lining the skull? This is very different from the dead bones you normally see.

Note how the shapes of each middle cranial fossa are quite different between the left and the right. The left greater wing seems to be anterior (towards the nose/ top of the picture). It does not look like a side bend to me – there is no bulge to the left? In Sutherland’s framework, probably a left lateral shear?

In palpating a clients head on a table, orienting to a squashed fluid balloon head, this pattern might present as the left hand towards the ceiling and the right hand towards the table. Often these are the obvious shapes and directions you feel in lateral shears, rather than feeling lateral translation of sphenoid.

Whatever we name it, and it is easy to get confused here, there is clearly experience and shaping by conditional forces. A great clinical approach is to try and work out the forces that have acted on the babies skull to generate the shapes you perceive.

For comparison here are three more real skulls, showing a variety of shapes.


Cranial base - three real skulls side by side

Cranial base – three real skulls side by side

cranial base labelled



skull da sein front v2 skull da sein inferior v1 skull da sein side v1
Real skulls are so fascinating. I took these pictures of a newly acquired skull at the Da Sein Institut recently.

There is a torsion across the occiput, notice the uneven shape of the foramen magnum. You can easily make out the borders of the temporal bone and the large mastoid processes of the temporals. And square eye sockets, bizarre.

This skull has a condylar canal on both sides – first time I understood that bit of anatomy could exist. You can see the canals in the middle image, posterior to the occipital condyles.

I recently came across Jerry Hesch writing on alignment and treatment of the sacrum. He makes a convincing case for the most common sacral misalignments being torsion on one of the two oblique axis as shown below. The graphic is mine (I found his images a bit hard to follow). The model is really simple, feel for the most posterior quadrant of the sacrum and you can work out how the sacrum is torsioned using the graphic below. Hesch says the most common pattern is posterior low left sacrum.

Sacrum Hesch_edited-2

From my experience of holding lots of sacrums over the last 13 years, I would agree sacrums are often torsioned along these oblique axis. It feels a really simple way to assess the sacrum and has helped me quickly clarify my experience during treatment this week.

He includes more testing in his full assessment of the sacrum, including springing (‘springing with awareness’) the ‘four corners’ or quadrants of the sacrum in childs pose. The most posterior corner will also be the stiffest, with no anterior posterior recoil. His treatment is really simple as well, sustained anterior posterior pressure of upto 20lbs for 2 mins.

The chapter is in a new book on soft tissue work by Eric Dalton. He has commissioned chapters from most of the leading fascia researchers and practitioners around right now. I have not heard of Hesch before, but he is in very good company in Eric Dalton’s book. Here is a video of him introducing his chapter.


Jerry Hesch chapter in (2013) Dalton E. (2013) Dynamic Body: Exploring Form, Expanding Function.

He obviously is a detailed thinker, you can access more of his writing here. (I have not explored in depth.)

See also

I have just discovered the site It looks like it has loads of good stuff on and is the source for this video.

FIGURE 1 | Illustration depicting the predominant veins and sinuses involved in the craniocervical venous outflow. Venous narrowing is depicted at locations of interest in chronic cerebrospinal venous insufficiency.

Illustration depicting the predominant veins and sinuses involved in the craniocervical venous outflow. Venous narrowing is depicted at locations of interest in chronic cerebrospinal venous insufficiency. Lazzaro M.A. et al (2011)

‘Recent reports have emerged suggesting that multiple sclerosis (MS) may be due to abnormal venous outflow from the central nervous system, termed chronic cerebrospinal venous insufficiency (CCSVI).’

Lazzaro M.A. et al (2011)

This is a very exciting article on the how venous outflow could be implicated in MS. The diagram above shows the sites the researchers have identified as being restricted.

There is a long tradition in cranial work of supporting drainage from the head by working at the thoracic outlet (or inlet, depending on what term you prefer, both are used for the same area). The first craniosacral therapist I ever saw would always start at the thoracic outlet, maybe he was on to something.

In the thoracic outlet hold the hands are above and below the base of the neck – upper hand spread over  the suprasternal notch, first rib and clavicles, the lower hand underneath the the cervical thoracic junction. I like to try and feel the shape of the hole made by the first rib and orient to the health of all the tubes moving through the region (dural tube, oesophagus, trachea, carotid sheaths). Pulsing arteries softening, spreading of the fascia sheets, easing of the movement of C7 and a shift in the first rib and clavicles all speak of change in this region.

The image above includes drainage routes via ‘spinal column drainage route’, ‘pterygoid plexus’ and ‘vertebral vein’ that are fairly new to me – nice bits of anatomy to appreciate.

Another route for cerebrospinal fluid (CSF) to leave the skull you can consider is shown below. A significant amount of CSF drains as lymphatic outflow from the cranial cavity via the ethmoid (and to a lesser degree perineural spaces of cranial and spinal nerves) and is collected by the lymphatic vessels of the head and neck (Pollay 2010).

This research helped me appreciate the dynamics of the ethmoid and cervical lymphatics as important in fluid draining from the skull. Pollay also indicates that poor outflow of CSF is not good for the health of the nervous system.

A great image from Pollay 2010 showing the dual outflow system for drainage of CSF. Outflow is via both the arachnoid villi into the venous sinuses and the lymphatic outflow (mostly through the ethmoid via CN I)

A great image from Pollay 2010 showing the dual outflow system for drainage of CSF. Outflow is via both the arachnoid villi into the venous sinuses and the lymphatic outflow (mostly through the ethmoid via CNI olfactory nerve sheaths)

‘The lymphatic system has been shown to develop earlier than that of the arachnoid villi and therefore appear to be a dominant CSF outflow route in the late fetal and early neonatal period. There is convincing evidence that the arachnoid villi system loses it efficiency with age, which can influence the total turnover rate of the CSF with possible neurodegenerative consequences.’

Pollay 2010

See also this post for more on the venous outflow in cranial work


Lazzaro M.A. et al (2011) Endovascular therapy for chronic cerebrospinal venous insufficiency in multiple sclerosis. Front. Neur., 14 July 2011 | doi: 10.3389/fneur.2011.00044

Pollay, M. (2010) The function and structure of the cerebrospinal fluid outflow system. Cerebrospinal Fluid Res. 2010; 7: 9. Published online 2010 June 21. Accessed 2/10/12 via

Massive ventricular enlargement, in a patient with normal social functioning(A) CT; (B, C) T1-weighted MRI, with gadolinium contrast; (D) T2-weighted MRI. LV=lateral ventricle. III=third ventricle. IV=fourth ventricle. Arrow=Magendie's foramen. The posterior fossa cyst is outlined in (D).

Massive ventricular enlargement, in a patient with normal social functioning
(A) CT; (B, C) T1-weighted MRI, with gadolinium contrast; (D) T2-weighted MRI. LV=lateral ventricle. III=third ventricle. IV=fourth ventricle. Arrow=Magendie’s foramen. The posterior fossa cyst is outlined in (D).

From article in The Lancet 2007 titled ‘Brain of a white-collar worker’

A 44 year old man presented to the doctor with a weakness in his leg. ‘His neurological development and medical history were otherwise normal. He was a married father of two children, and worked as a civil servant.’ On CT scan they found an incredible brain that is mostly ventricles.

Wild, how does that work?

Real skulls are so cool. This skull came from someone with an amazingly uneven jaw and really strong temporalis muscles – indicated (I think) by the ridges pulled out on the parietals. Note also the wormian bones at the pterion and asterion.

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