Upper Neck Anatomy and Neurology-For The Lay Person
Why are the atlas and axis unique and special? The atlas is a two-ounce bone on which rests the head weighing 10-13 pounds. Furthermore, the skull rests on two joints on the surface of the atlas called the occipital condyle.
The atlas then fits on the axis(c-2) which has a projection up through the ring of the atlas called the dens. (fig. 1) This projection allows for stability and allows the neck to rotate around the axis. Inside of these two bones is the most important structure in the entire body, called the brain stem.
Furthermore, this region of the spine has more mobility than any other in the spine. The head can rotate left and right 180 degrees, backward and forwards 130 degrees, and laterally towards the left and right shoulder 90 degrees.
This freedom of motion has its drawbacks. Because of the freedom of movement, the neck skull junction is the most susceptible area of the human spine to injury. What does this have to do with your health? Keep reading.....
How Does Neck Injury Impact Your Health?
Trauma can induce forces into the neck that can cause the atlas and/or axis to misalign. Injury to the ligaments, soft tissue, and muscles can lead to the joints in the neck losing their normal motion.
The scientific literature shows that decreased joint motion, especially in the upper cervical spine, leads to a host of deleterious effects on function and health. Dr. Mike Flanagan proposes in his 21-page paper titled " The Role Of the Craniocervical Junction In The Craniospinal Hydrodynamics And Neurodegenerative Conditions, outlines an impressively detailed argument for the overwhelming evidence of atlas axis misalignments role in a chronic disease process.
Others including Dr. Scott Rosa have shown that upper neck misalignments at the CCJ(skull c-1 c-2 junction) decrease not only cerebral spinal fluid flow but also brain blood flow. Decreases in blood flow to the brain over the long-term can lead to a host of health problems including, cognitive problems, depression, multiple sclerosis, and Parkinson's disease.
There are several different theories that help explain how an atlas or axis misalignment can cause interference to the central nervous system causing a cascade of dysfunction throughout the body. John F. Grostic championed one theory known as the dentate ligament theory.
This theory gives credence to the atlas misalignment causing mechanical traction on the brain-stem. Other theories such as dysafferentation theory and the myo-dural bridge theory have been explored.
The truth of the matter is that all of these different mechanisms are at play. And like nutrition, there are many more discoveries to come that will help explain the upper cervical spine's role in the health and disease process.
From a musculoskeletal vantage point, injury to the upper cervical spine has a global effect on body posture. (fig.2) Postural muscle tone in the spine is controlled in the brain-stem. Injury to the neck can cause an imbalance in muscle tone and can be responsible for a host of musculoskeletal complaints.
Low back pain, neck pain, leg pain, sciatica, TMJ and other pain syndromes can have their roots in upper cervical spine injury. The effects of the upper cervical spine on overall health are not even on the radar of mainstream health care.
What is an Upper Neck Chiropractor?
Upper Cervical Doctors are specially trained to locate and correct misalignments in the upper neck region. Objective neurological tests are run to determine if there is a problem and if there is which vertebrae is involved. Once a problem is located several digital x-rays are taken of the joints of the vertebrae.
This is done to "see" where the spine has misaligned and allows the doctor to measure the magnitude and direction of the misalignment. Then a precise correction is made. With upper cervical chiropractors, there is no twisting popping or pulling.
Once the correction has been made the patient is rested in a bed for 30 minutes to allow the body to reposition the segment. Then over a period of time, the patient is monitored to determine whether they need correction or not.
The goal of the care is for the corrected vertebrae to stay corrected. The longer the vertebrae stays in its normal position the faster the body is able to heal and repair. Once the patient is stabilized they are encouraged to get checked once a quarter to maintain the gains they have received.