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TMJ - One of the smallest joints packing the biggest punch.

An often overlooked area in clinic work, the temporomandibular joint could be responsible for a vast number of seemingly unrelated presenting symptoms.

By Gus de la Querra

Look at any boxing match with a KO - a good hook to the jaw invariably signals the end of the fight. So, how important is the TMJ? Have a read and see what you think..

TMJ and structure

Movement of the TMJ is very closely related to the second cervical vertebra, C2 or also known as Axis. One might think that when the mandible opens and closes, its movement is centered around the condyle in the TMJ itself. However, this is not the case. According to the Quadrant Theorem of Guzay, the axis of rotation of the mandible lies exactly at the odontoid of C2. (The odontoid is the upward, toothlike protuberance from the second vertebra, around which the first vertebra rotates.) When the mandible moves downwards, this generates a pulling force, loosening the muscles around C2. Likewise, when moving up (i.e., when closing the mouth), it generates a pressure, which tightens the muscles around C2. This means that in an occlusion with decreased vertical dimension will aggravate muscle tension around C2 when the mouth is closed. Therefore, it is clear that distortion in TMJ will affect the position of the Axis too.

Of all 24 vertebrae in the spine (7 cervical, 12 thoracic, 5 lumbar), there is only one vertebra with an odontoid/axis, which is C2. Therefore, the Axis plays a key role in the balance of the entire spine. Together with the TMJ, C2 is the most significant variable affecting the entire spine structure.

So what happens next after subluxation of Axis? The rest of the spine collapses like in the domino effect even affecting position of the cranial bones and pelvis. This is explained by Lovetts reactor relationship below.