Skull Deformation and Correction in Infants
Unintentional infant skull deformation has followed humans throughout their upright history. But what's more intriguing is that the practice of intentional/artificial skull deformation (molding) goes way back in history as well. The process of molding the infant skull was accomplished with special shaping pads and straps gradually tightened and adjusted over time. More recently, physicians use special orthoses such as the picture on the left, which is a modern cranial orthotic device used for correction of skull deformation produced by the Hanger Prosthetics and Orthotics and Orthopedic Group located in Austin, Texas.
In either case, deformation affects the special joints of the skull called sutures and developmental problems with the sutures can result in deformation of the skull. My investigation into the link between upright posture and neurodegenerative diseases started while studying the sutures and base of the human skull.
Many different conditions and diseases affect the sutures of the skull. One important condition in children is hydrocephalus, which causes the sutures to stay open. The other condition is called craniosynostosis, which is discussed at length below, occurs when the sutures close too early. Hydrocephalus causes a child's head to enlarge fairly symmetrically like blowing up a balloon. Craniosynostosis, on the other hand, causes irregular skull shapes and sometimes undersized compartments for the brain.
Among other things, both hydrocephlus and craniosynostosis can result in an increase in intracranial pressure. As I began to dig deeper into intentional artificial skull deformation, I began to suspect that in certain cases it may have been done for the correction of increased intracranial pressure and hydrocephalus, which I will also discuss further below.
Unintentional Skull Deformation Caused by Humans
One common type of unintentional skull deformation caused by humans is called cradleboard deformity. This type of deformity is caused by cradleboards at the head of the infant's bed which sometimes pressed up against the top or back of the soft infant skull and over time compressed it causing it to become flattened. It doesn't take long to change the soft infant skull.
Some experts suggest that the Eskimos and indigenous people of North and South America intentionally deformed infant heads for aesthetic purposes. I tend to think it was more unintentional than intentional, at least initially, and they did it to protect the baby, especially the neck.
There is no exact time when an infant first starts to hold its head upright but basically the neck remains relatively weak and floppy for several weeks following birth. Even after that, it remains relatively week throughout infancy and childhood so the devices may have been used for many reasons to protect their children during early developmental years when they are most vulnerable.
The painting below taken from Wikipedia shows one particular type device used by the Eskimos of North America that caused deformation of the skull. My guess is that it was caused by mothers confining their infants in cribs for safety or strapping their heads to backpack-like papooses and sleds to prevent them from bouncing around during travel up and down steep cliffs and over rough terrain such as in sleds. That would make them similar to toddler seats for cars. It would also make similar sense to strap a baby's head to a papoose to prevent it from flopping around as mothers moved about. In either case, for whatever reason they did it, whether it was intentional or unintentional, the devices caused deformation of the skull. In this particular case it caused the skull to become flattened in the front and back.
More recently a modern form of cradleboard skull deformation occured called plagicephaly. Plagicephaly occurs when the front or the back of the soft infant skull becomes flattened (as mentioned above). In this case it happened as a result of pediatricians advising mothers to leave their babies on their backs when in a crib in order to prevent sudden infant death syndrome. The prolonged periods spent laying on the back during infancy caused the rear of the skull to flatten. Technically deformation due to sleeping positions is called positional plagicephaly.
According to clinical study by Dr. Hryar Shahinian and others of the Skull Base Institute, some cases of positional plagicephaly may also occur as a result of preterm labor before 37 weeks. It can also occur due to a prolonged first stage of labor, which occurs between onset of contractions and full dilation of the cervix. At the end of pregnancy the baby's head is pointed downwards and getting ready for delivery. During this time the head is relatively squashed into the tighter confines of the mother's pelvic outlet. They also noticed a much higher incidence of problems in boys, which they suspect is probably due the larger size of the male head.
Among other things, plagicephaly compresses and deforms the posterior fossa, forcing the brainstem and cerebellum forward. Interestingly, a hypoplastic (undersized) posterior fossa similarly pushes the cerebellum forward and down into the foramen magnum and is one of the main causes of Chiari malformations. Deformation of the rear of the skull, such as plagicephaly, can pose similar risks.
Craniosynostosis and Skull Deformation
Craniosynostosis comes from the word forms cranio which means skull, syn which means together and ostosis which in this case means abnormal bone growth. Craniosynostosis occurs when the membranous bones of the cranium come together and close prematurely. The membranous bones of the cranium form the cover over the cranial vault that contains the brain. They are called membranous bones because they grow within the outer membrane of the brain and follow the growth of the brain as an infant matures. The membranous bones stay partly open for many years in humans but slowly close over the course of a lifetime.
Craniosynostosis of the membranous bones of the cranium can cause developmental skull deformation. Slightly assymetrical irregular shapes of the head typically have no impact on brain development provided it has enough room for growth. The picture below on the right shows a perfectly healthy and obviously very happy baby with slight assymetry of the face and cranial vault due to craniosynostosis.
During the growth years the developing brain creates significant pressure on the bones of the skull as it expands in size. Because the joints of bones that form the cover over the brain stay more open and pliable due their unique design, when confined in one area the brain simply creates more space by pushing out in another direction.
Typically, because the skull cannot expand perpendicular to the the joint (suture) that has closed prematurely, it compensates by growing more in the direction perpendicular to the joint (suture) in the area that is still open. For example, if the suture at the top of the skull (sagittal) closes prematurely the growing brain will tend to push toward the temporal suture (lateral to the sagittal) if it is still patent resulting in a buldge on the side of the skull as in the picture.
In extreme conditions premature closure of the sutures of the skull overly crowds the brain into a relatively smaller container. In cases in which the compensation by buldging out elsewhere in the skull fails to provide sufficient space for the growing brain, craniosynostosis can cause an increase in intracranial pressure which can lead to visual or mental impairment. It can thus affect cognition and intelligence. But medical reasons aren't the only reason for using cranial orthoses. Some parents use them for cosmetic reasons to correct deformation and restore symmetry to the infant skull.
Craniofacial and Base Anomalies
The bones of the face and base of the cranium are called cartilagenous bones. They are related to the musculoskeletal system and follow its growth pattern in children. Abnormal development of the face causes what are called craniofacial anomalies. In addition to the face, there are developmental anomalies that are associated with deformation of the cranial base, such as small or missing foramen (openings or holes) for the passage of nerves and blood vessels.
One example of a small or missing opening in the base of the skull is atresia (absence) or hypoplasia (undersized development) of the jugular foramen. An undersized or absent jugular foramen can result in poor drainage of the skull and subsequent increased intracranial pressure. Interestingly, the first anatomical special specimen skull I studied, called a demo skull, had an undersized jugular foramen. The sutures nearby were closed. On the other hand the opposite jugular foramen was extra large and the sutures were wide open.
On the other side of the world, Dr. Franz Schelling's research into the connection between insufficient venous drainage of the brain and multiple sclerosis started after he noticed a discrepancy in the size of the jugular foramen in patients with multiple sclerosis. Even more recently, Dr. Paulo Zamboni associated chronic cerebrospinal venous insufficiency (poor drainage of the brain) with multiple sclerosis. It may be associated with other neurodegenerative diseases as well. For further reading on these subjects go to skull shape and backjets and CCSVI respectively.
Another important example of a skull base anomaly that causes deformation of the cranial vault is called as platybasia, in which the base of the skull is too flat. Platybasia has been assoicated with functional Chiari malformations. Still another important example of and anomaly causing deformation of the base is one in which the clivus portion of the base of the skull is too short. An undersized clivus has been further associated with hypoplasia (underdevelopment) of the posterior fossa. An undersized posterior fossa is another key cause of Chiari malformations.
Intentional Infant Skull Deformation
Interestingly, my research started while studying the impact of artificial skull deformation on the base and the sutures. Artificial infant skull deformation was widely practiced by the former indigenous people of Peru and Bolivia but nobody knows exactly why they did it. Whatever the reason, the practice of artificial skull deformation caused the sutures to stay open into adulthood.
In intentional infant artificial skull deformation, physicians or shamen of the day used some type of special pads with fiber bindings to progressively alter the shape of the head. The question is did they do it for aesthetics or for correction of an existing problem? Interestingly, in this regard, doctors are now using what are called cranial orthoses that are similar to bicycle helmets(see picture at top of page) for remodeling and correction of skull deformation in infants. Some orthoses are solid and simply surround the head to mold it. Others have custom openings in the helmet to direct the growth of the brain and skull toward the direction of the opening.
The sutures are supposed to join the membranous bones together. They are separated in human infants to make it somewhat easier for the mother and baby to survive delivery of a relatively large head. The sutures start to knit together soon after the baby is born. The metopic suture which splits the forehead of the fetus into two separate pieces is usually closed at or soon after birth. Within the first two years the soft spots called fontanelles will be gone and the separate membranous bones will be linked by joints that look like stitches that are called sutures. The outer surface of the sutures, however, will stay open well into adulthood due to the effects of upright posture on bio and fluid mechanics in the skull.
The method of artificial skull deformation used in Peru and Bolivia caused the sutures of the skull to remain open from the inside to the outside into adulthood when they should have at least started to close on the inside. To me this suggests an increase in intracranial pressure. Increased intracranial pressure in children is often due to hydrocephalus and that is how I got started looking into hydrocephalus and neurodegenerative diseases.
At first, when looking at the skulls like the one above, I thought the physicians or shamen of the day had unintentionally caused hydrocephalus due to the skull deformation similar to the consequences of extreme craniosynostosis. Then it occured to me perhaps they were trying to treat hydrocephalus. Why else would people go to such extremes?
Similar to skull deformation, hydrocephalus is as old as humans are. It's my opinion that humans are predisposed to hydrocephalus and skull deformation due to upright posture and the unique design of the skull, spine and circulatory system of the brain. The key sign in hydrocephalus is a rapidly developing oversized head. People, community healers and especially mother's most likely knew the signs of hydrocephalus long before recorded history. The signs are easy to see.
Closer inbreeding in tight knit mountain and valley communities of Peru and Bolivia could have passed on a genetic skull design flaw such as an undersized cranial vault relative to the size of the brain. As mentioned above, craniosynostosis can cause an increase in intracranial pressure but so can a condition called craniodysostosis such as an undersized base of the skull, especially the posterior fossa.
Rather than hydrocephalus perhaps they were attempting correction of craniosynostosis. But this seems hardly likely since the outcome was far worse if the object was correction and restoration of normal shape and symmetry. On the other hand, if they were attempting correction of hydrocephalus, they were far more successfull at it than their western contemporary physician counterparts before the advent of shunts. The reason why is because judging by their molar teeth they obviously lived to be adults. In western cultures, before shunts, children were often severely mentally impaired and died young as a result of hydrocephalus. That would make the physicians or shaman of the former indiginous people of Peru and Bolivia smarter than we give them credit for doing what they did. Fortunately today, due to shunts, children can, in many cases, live normal lives.
Unfortunately, we can only guess why the former indigenous people of Peru and Bolivia performed intentional skull deformation on so many of their infants. Suffice it to say however, the extreme skull deformation altered the flow of blood and CSF which may have compensated for the hydrocephalus or it opened new pathways.
Surgical Decompression of the Skull and Brain
In this regard some skulls also had trepinations. Trepinations are surgical holes cut in the skull. They are the oldest form of surgery. Currently surgeons cut holes into the skull to gain access to the brain for various surgical procedures. They refer to the procedure as a craniotomy. Among other things, trepinations and craniotomy can also be used to decompress the brain by allowing it space to expand when necessary.
Trepinations would work similar to craniotomy. As an analogy, in homes built in cold climates new codes require expansion kits on the domestic hot water heaters. The problem in northern climates is that incoming water is very cold as it enters the hot water heater. The heat of the hot water heater causes a rapid expansion of the water volume. The rapid expansion of the volume in the pipes can break pipe joints. The expansion kits have a diaphragm that moves up to increase space when necessary to absorb an increase in volume. As volume goes back down so does the diaphragm. The diaphragm can be likened to the exposed dura in the skull.
Another form of craniotomy to relieve pressure and decompress the brain and cord in Chiari malformations uses enlargment of the foramen magnum (the large hole in the bottom of the skull)combined with shaving down or removing the rear portion of the first cervical vertebra called atlas or C1. Shaving down or removing the arch of bone on the backside of the upper cervical spine creates more space for the brain to expand. Additionally, sometimes duraplasty is used to make the brain covering more pliable and to increase its expandability.
The picture on the left of a duraplastly procedure is from the Mayfield Clinic of Brain and Spine Surgery in Cincinnati, Ohio, which, among other things, specializes in Chiari malformations. In duraplasty the spine and skull are shaved down as mentioned above which increases space and allows the dura to expand. But the dura is tough and its expansion is limited so some surgeons cut out a piece of the dura and then place a larger patch over the hole with a graft of tissue. Duraplasty effectively increases the size of the comparment but also causes additional complications and risks due to cutting through the dura mater of the brain. More recently, surgeons are choosing to score rather than cut a hole in the dura. Scoring the dura weakens its walls making it more expandable.
The trepinations (craniotomy) in the artificially deformed skulls exposed the dura of the brain. Although, there is no way of knowing for sure, I suspect the dura probably wasn't scored as physicians do nowadays. Nonetheless, the trepinations would have provided space for a degree of expansion of fluid volume in the brain. To protect the exposed dura the physicians of the day used shells and other natural materials that were available. The coca leaf was also readily available and was most likely used as an anesthetic, as well as to decrease bleeding during surgery.
Physicians also use surgery sometimes to correct skull deformation due to craniosynostosis. To correct craniosynostosis they cut open the prematurely closed suture and patch over the opening with more supple graft tissues taken from the patient. The increase in flexibility provides more room for the brain and skull to grow normally until development is complete.
Gravity and Head Shape
Aside from unintentional and intentional artificial infant skull deformation, gravity and upright posture play a major role in determining the shape of the brain and head. Conversely, gravity-free environments such as space drastically alter fluid mechanics in the brain. It's one of the topics I cover in the last chapter of my book.
Just for interest I pose the possibiltiy that if in the future humans should leave earth for good and their babies are born in lower gravitational conditions somewhere other than mother earth, the brain and skull will enlarge and become hydrocephalic in appearance. Over time evolution will take its toll and humans will become humanoids as they become shaped by their new environment. Most likely physicians or shamen and parents of the day will initially elect to control the size and appearance of the head in order to maintain their human characteristics. An easy way to do it would be to use cranial orthoses.
Skull Shape and Brain Health
The infant skull is not something to be tampered with lightly because the outcome can be devastating and will last for a lifetime. In this regard, the shape of the skull determines the position and layout of the brain and brainstem inside the cranial vault. It also determines the pitch, angle and course of circulatory pathways in the brain. The unique design of the base of the skull due to upright posture predisposes humans to hydrocephalus and Chiari malformations. Undersized cranial compartments cause further complications. The size and layout of the cranial compartments may explain gender and racial differences in incidence of certain neurodegenerative diseases.
Currently, craniotomy and shaving down the rear part of the first cervical vertebra are used to decompress the brain in Chiari malformations. Duraplasty further decreases pressure. New and less invasive surgical procedures such as those being developed by the Skull Base Institute will probably develop even better alternatives.
In the mean time, less invasive procedures such as professional manual craniopathic molding and CSF manipulation should be investigated for its potential impact on craniosynostosis, communicating hydrocephalus and skull base problems such as hypoplasia of the posterior fossa. The founder of Osteopathic Craniopathy, Dr. Sutherland treated and documented cases of successful remolding of cases of craniosynostosis. The method and reason for using it is all based on sound science. Specific upper cervical and special spinal decompression procedures may also be helpful in removing musculoskeletal impediments associated with skull deformation. Some cases may require professional co-management for the best results.
In contrast to the impact of skull deformation, deformation of the spine can also affect the position of the brain inside the cranial vault. But that's another story that I will cover later as this website develops.
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