Chiari malformation is a subject I discuss at length in my book along with Dandy Walker syndrome and pressure conus conditions, so I won’t go into it detail here. Suffice it to say that, among other things, Chiari and pressure conus type conditions plug the foramen magnum and verterbral venous outlets.
Recent research shows a significant correlation between trauma and Chiari/CTE type conditions. It is my opinion, that hyperflexion type strains of the cord, in which the neck overstretches as it is pulled foward by the weight of the head moving in a chin toward the chest direction, can traction the brainstem and pull it down toward the foramen magnum. On the way down it causes a compression deformation of the larger part of the brainstem in the foramen magnum. As the hyperflexion strain is released the brainstem then returns to normal size faster than it can return to its normal position above the foramen magnum creating a pressure conus/Chiari type condition.
Flexion strains of the cord cause the brainstem to get stuck due either to traction strains coming from above, such as a head stuck in the wrong position forward of the gravity line, or from further down in the spine, such as a twisted or tilted pelvis. It can also come from expansion of the brainstem in the foramen magnum. The action would be similar, for example, to pushing a cork into the top of a wine bottle. The cork compresses and deforms as it enters the bottle top. As the driving force is released the cork then expands and becomes trapped in the bottle top. If you turn the bottle upside down the wine cannot get past the cork. In the brain, blood and cerebrospinal fluid similarly get trapped.
Craniocervical misalignments may also play a role in Chiari malformations and Dandy Walker syndromes seen in newborn infants and children. Birth and childhood traumas can cause tremendous strain on an infant’s neck if the presentation isn’t perfect. Likewise, young children with developing neurological and musculoskeletal tissues are also more vulnerable to trauma.
Among other things, Chiari malformations can affect venous drainage in the brain. In this regard a new theory suggests that the cause of MS is due to chronic cerebrospinal venous insufficiency. It may play a role in other neurodegenerative diseases as well, such as Parkinson’s and Alzheimer’s. More importantly, in addition to venous drainage problems, Chiari malformations can also cause hydrocephalus in the brain above it, and cavities in the central canal of the cord below it. Normal presssure hydrocephalus, or NPH, is a key subject covered in my book. NPH is most likely the cause of many of the signs and symptoms seen in Alzheimer’s, Parkinson’s and mutliple sclerosis.