As a craniosacral therapist I rely on the theory (or fact) that our cranial bones are “not” fused. Allopathic and mainstream medicine in the US still do not recognize officially this view which to many CST practitioners is a “fact”.
Anatomy supports that the cranial bones are “not” fused, but as is the case with other holistic, naturopathic, and functional medicine realities, mainstream medicine lags behind in adopting certain holistic or revolutionary ideas. This was the case with gluten intolerance, I remember the day my family physician was surprised to hear me say that I didn’t eat gluten.. he didn’t know gluten intolerance was a fact for me. In my practice I utilize systems that work and produce results. Eventually, mainstream catches up, hopefully.
My approach is naturopathic and energetic, I am focused on balancing mind & body, detoxing trauma, negative beliefs as well as physical toxins, nourishing with nutrition and healthy thoughts.. traditional and modern herbalism, TCM, and energy psychology. I work with the mind-body-energy system.
In the US, mainstream anatomy books and classes show students separate cranial bones. Students see and handle the separate bones, they are taught that cranial bones are fused, not separate.
This is a big problem in the world of healing, most believe what we are taught, without questioning, instead of learning from what we experience, and observations in the field.. clinical experience and findings.
To get cranial bones apart: You turn the cranium over, pour beans into the large opening (foramen magnum) where the spinal cord exits, then add water. The beans expand, the sutures (cranial joints) separate. The bones are not fused in most people.
There’s connective tissue in the sutures. Connective tissue is similar in color to bones, so if you only look at dried specimens you could mistake it for bone.
Italian anatomy books teach that the bones don’t fuse. Movement of the cranial bones has been measured with strain gauges. Before and after photos show changes in position of the bones after cranial work. You can see the changes yourself in a mirror. Yet, allopathic and mainstream anatomy education in the US is blind to this. Despite thousands of CST therapists in the US healing hundreds of thousands of clients, this fact remains ignored in the mainstream health system, for now.
I found a great article written by Melissa Ventimiglia, D.O. which I will quote below.
One of the components of the cranial concept for practitioners who practice cranial osteopathy or craniosacral therapy is that the bones of the head move along the sutures. The movement can be described as an expansion and compression that take place much how the rib cage moves during respiration. This idea has been highly controversial since it was first presented to the world over 60 years ago. To this day, there’s plenty of criticism that this concept is based on ‘pseudoscience.’ Many state that there is ‘no research’ supporting this idea. This statement is incorrect. There may not be sufficient evidence at this time supporting this idea. However, there is much more research showing that there the bones of the head can than there is research showing that the bones of the head do not move. Much of this research is on the Cranial Academy’s web site.
I found a dissertation that discusses much of the research about the fusion of the sutures here. I am not arguing that this is sufficient research because I do feel more is needed. I want to discuss 5 reasons I have found that support the bones of the head do move.
Reason 1: Embryological
Side view of some of the bones of the skull
Why are there sutures in the head? If you look at a skull, there are sutures throughout the head making each bone identifiable. This may seem insignificant as evidence but during development, there are many bones that form in separate parts and do actually fuse to form one bone. For example, each pelvic bone develops as three separate parts (ischium, ilium, and pubis) that fuse into one bone with no sutures between them. There are many examples of this during development. This even takes place in the head. The occiput forms by the fusion of 4 separate components. This fusion is complete and does not have any sutures between them. There are sutures between the occiput and the bones it articulates with. Clearly the human body would be capable of completely fusing the bones of the head if it intended it to do so. This fusion, however, does not take place or one would be unable to distinguish each separate bone of the skull once fusion had taken place. In addition, skulls can be disarticulated using the expansive properties of rice to separate the bones at the sutures. So if the body is capable of completely fusing the bones of the head, then why does it not do this?
Reason 2: Adaptation
Although there are not large amounts of movement in the head, there is some. Proper motion allows the head to be pliable to better absorb the shock of a trauma or changes in intracranial pressure. Part of the purpose of the skull is to encase and protect the brain. If one receives a blunt trauma to the head, the pliability allowed by movement of the bones of the head allows the bones to absorb much of the impact. This would allow the brain to be less affected by the trauma. If the skull fused, then the skull would be very hard like the outer casing of a helmet. A blunt trauma would break the skull easier like an egg shell and the force would be transferred to the brain more strongly. By not fusing, the head can then change and adapt better to changes in intracranial pressure. If a scenario occurs where the pressure in the head changes (such as flying or having a cold), then it would be helpful for the bones to be pliable and expand. That way, when the pressure in the head changes, the effect on the brain is minimized. Therefore, in terms of being able to handle traumas and changes in pressure, it would make sense of the head to be able to expand.
Reason 3: Braces
We have evidence that the bones of the head can move all around us. If the bones of the head fuse and could not move, there would be no reason for braces. Braces are based on the idea that the head is pliable and can be reshaped to align teeth.
Reason 4: Motion Testing
Part of the reason that there is so much controversy about whether or not the bones of the head move or not is because most practitioners put their hands on a persons head and palpate the subtle movement taking place under their hands. Others who come along who cannot palpate this motion, then argue that this cannot be felt. Although I can feel this subtle motion, I feel restrictions in the sutures by getting a hold of the accessible bones of the head and move them through their range of motion. I compare how one side moves compared to the other. Usually one side moves better than the other. Under normal circumstances each bone has a small range of motion. There is significantly more motion than taking a plastic skull and trying to move it. By understanding where there are restrictions in the sutures, then I can work on freeing them up until both sides feel more symmetrical in their movement. I prove this idea to myself every day that I am at work.
Reason 5: Layout of Sutures
Finally the last piece of evidence I have found is in the sutures themselves. This goes back to anatomy. If one studies the way the motion described in the skull and the anatomy of the sutures, then one could see this idea as being plausible. There are different types of sutures and they articulate differently depending on the area. For example, the frontal bone overlaps the parietal bone medially, but as one moves out further along the coronal suture, there is a transition spot followed by the parietal bone overlapping the frontal bone. The sagittal suture for example, acts more like a hinge and the suture is put together in a way that allows for this type of a function. These are just a few examples although this takes place with the way all the bones articulate with each other. Simply put, the bones of the head act like a 3D puzzle that allows the head to go through its motion. In addition, dural membranes in the head come out externally through the sutures. Evidence for this is that epidural bleeds in the head do not cross suture lines because the dura travels externally at the sutures. The dural membranes inside the head act as a barrier preventing the bones of the head from fusing completely.
Can the bones of the head fuse? Absolutely. Anytime you take a joint and prevent it from moving for an extended period of time, then it will fuse. These are pathological cases. Why would the head be any different? Above are the reasons that I believe the bones of the head do move. Yes, more research is needed but it is time that people start to logically consider the idea. The human body develops the way it does for specific reasons. None of it is random. Perhaps we need to consider why there are sutures and the skull does not fuse into one solid bone. Many healthcare providers and researchers stubbornly state the bones of the head fuse. They ask for research showing that the bones of the head move and will discredit anyone who states they do move because ’there is no research.’ I have never come across anyone who has ever cited a legitimate research study showing that the bones of the head without a shadow of a doubt actually do fuse. My experience as a provider of Osteopathic Manipulative Treatment (OMT) has shown me time and again that releasing dysfunctional structures in the head can release pain and tension throughout the rest of the body.
William Garner Sutherland, DO (1873-1954), discovered, developed and taught cranial osteopathy in the early to mid-1900s. Dr. Sutherland referred to his discovery as Osteopathy in the Cranial Field (OCF). He never failed to emphasize that the cranial concept was only an extension of, not separate from, Dr. Still’s science of osteopathy. Dr. Sutherland was the first to perceive a subtle palpable movement within the bones of the cranium. He went on to discover the continuity of this rhythmic fluid movement throughout all tissues of the body.
While a student at the American School of Osteopathy in 1899, Dr. Sutherland pondered the fine details of a disarticulated (separated bone-by-bone) skull. He wondered about the function of this complex architecture. Dr. Still had taught that every structure exists because it performs a particular function. While looking at a temporal bone, a flash of inspiration struck Dr. Sutherland: “Beveled like the gills of a fish, indicating respiratory motion for an articular mechanism.”
Anatomy textbooks stated that the cranial sutures were fused and unable to move in adulthood. Dr. Sutherland originally thought his inspiration to be absurd and resisted the notion that the skull bones could move. This idea consumed him and became the motivation for his singular, detailed and prolonged study of skulls, and experimentation upon his own head. Over many years of intense study, Dr. Sutherland came to discover a previously unrecognized phenomenon. The anatomy had been described by others, but it took the unique genius of Dr. Sutherland to put it all together. He named his discovery the primary respiratory mechanism and recognized this phenomenon as life’s purest and most vital expression. As data is gathered throughout the medical and scientific disciplines, the fundamental genius of Dr. Sutherland’s observations becomes ever more validated. In time, this cranial concept may become regarded as one of the most important discoveries in human physiology.
The Primary Respiratory Mechanism (PRM)
In his own unique and very elegant style, Dr. Sutherland had identified the same self-healing mechanism discovered by Dr. Still.
Primary – It is a system that comes first. It underlies all of life’s processes and gives dynamism, form and substance to all of anatomy and physiology, driving all functions of the body.
Respiratory – It is the spark that gives rise to the breath as it moves through the tissues. It is the foundation of metabolism. It enables the exchange of gases and other substances between compartments of the body.
Mechanism – It manifests as a specific motion of the body, a system composed of many parts that work together to create a whole, greater than the sum of the parts.
This primary respiratory mechanism has five basic components:
The inherent rhythmic motion of the brain and spinal cord.
The fluctuation of the cerebrospinal fluid (CSF) that bathes and nourishes the brain and spinal cord.
The shifting tensions of the membranous envelope (dura mater) surrounding the brain and spinal cord. This entire membranous structure acts as a unit and is called a reciprocal tension membrane.
The mobility of the cranial bones.
The involuntary motion of the sacrum (tailbone) between the ilia (hip bones).
Just as the lungs breathe and the heart beats with a rhythmic alternating expansion and contraction, the central nervous system (CNS) also has its own involuntary rhythmic motion. Dr. Sutherland described this inherent activity of the CNS as a respiratory motion with “inhalation” and “exhalation” phases. The hands of a skilled osteopathic physician interact directly with the primary respiratory mechanism to bring about a therapeutic response. Primary respiration is the guiding principle; it is the inherent intelligence within. This primary respiratory mechanism actually expresses itself through every cell of the body, influencing all body functions. Physicians trained in cranial osteopathy can place their hands on any part of the patient to perceive and influence this important mechanism.
Cranial osteopathy is the study of anatomy and physiology of the cranium, the central nervous system, and the cerebrospinal fluid, and their inter-relationship with the body as a whole. It may be applied for the prevention and treatment of disease and enhancement of health, within the practice of the science of osteopathy.
This PRM actually expresses itself through every cell of the body, influencing all body functions but it has five basic components:
The rhythmic motion of the brain and spinal cord (Central Nervous System – CNS).
The fluctuation of the cerebrospinal fluid (CSF) that bathes and nourishes the brain and spinal cord.
The shifting tensions of the membranous envelope (dura mater) that surround the brain and spinal cord. The entire membrane structure acts as a unit and is called a Reciprocal Tension Membrane.
The mobility of the cranial bones.
The involuntary motion of the sacrum (tailbone) between the ilia (hip bones).
The PRM moves as a whole. The brain and spinal cord have an inherent motion.
The brain coils and uncoils. As this happens the, spinal cord moves up slightly during the coiling and then downward during the uncoiling phase. The fluids surrounding the brain and spinal cord move in one direction then the other.
The Reciprocal Tension Membrane is attached to the bones of the skull, at the top of the neck and then to the sacrum and finally to the coccyx via a thin strand of fibrous tissue. As the brain coils and the spinal cord moves upward, so do the membranes. As the brain uncoils, the spinal cord drops and the membranes follow.
As the membranes move, they transfer the movement to the bones to which they are attached. The cranial bones and the sacrum are moved as the membranes shift upwards and down. It is the membrane attachments that link the head to the sacrum and allows them to move in a coordinated rhythm.
The motion of the Primary Respiratory Mechanism is an ebb and flow or an inhalation and exhalation that can have a profound influence in health, especially when it changes in quality, amplitude and frequency. The PRM resides between the cranium and the sacrum. Practitioners are able to experience the PRM directly with their hands and can connect with it in a way that brings a therapeutic response. And so we have Craniosacral Therapy.
