Atlas Orthogonal explained

The major chiropractic premise:

  • the nervous system has a regulating effect over all bodily functions
  • interference to nerve function (including brain and peripheral nervous system incorporating peripheral sense organs such as the eyes, ears and concerning smell) can result in poor health
  • the skeletal system, primarily the spine can interfere with the nervous system via joint subluxation or misalignment

The AO premise:

  • the first and second vertebrae in the neck should line up with the skull (occiput) at right angles or orthogonally.
  • if they are not orthogonal, subsequent imbalance of body structure will eventuate due to compensatory changes.
  • compensatory changes are affected by nervous system interference, irritation or dysfunction.
  • this may lead to poor organ function, muscle spasm causing shoulder or pelvic girdle distortion, over time, if not corrected

The Technique

Atlas (the first vertebra in the neck) Orthogonal (at 90 degrees) recognises the whole influence that the upper cervical (upper neck) area has on body function. It is now thought that input into the brain from the spinal structures is the main influence on health which chiropractic affects.

This input is what chiropracic care seems to normalise through high velocity, specific manual force input. This influence is perhaps greatest at the occipito-atlanto-axial joint complex. That is, the occiput, or base of the skull, on the atlas, which contacts the axis, or second neck vertebra. If the atlas is subluxated (misaligned, not moving correctly, or adversely affecting nerves), then myriad health problems may arise

How the instrument ‘works’:

Eugene T. Patronis, Jr., Ph.D., professor at the School of Physics, Georgia Institute of Technology describes the operation of the Atlas Orthogonal Adjusting Instrument as follows:

“A mechanical impulse is imparted to the metal stylus by means of a spring loaded plunger. The strength of this impulse is determined by the initial degree of compression given to the plunger spring. The impulse imparted to the stylus by the plunger excites a compressional wave in the stylus. The velocity of this wave in the stylus material is determined by the square root of the ratio of the Young’s modulus to the density of the stylus material. At the patient-stylus interface, dependent on the impedance match, a portion of this wave energy is transmitted into the patient and a portion is reflected back to the plunger.”

Download scientific article on AO for more information –  AO article 2010

How is the Atlas determined to need and Adjustment?

• a thorough history and examination is conducted
• this includes scanning palpation, and a leg length check,
• a specific set of AO x rays are taken
• the information is presented, along with choices, risks, etc, to the patient who may elect to have it corrected

For more information regarding this technique please see