TMJ and Posture, Yes it’s All Connected: The Chain Theory of Body Linkage

Abstract

The physiology involved in the integration between the rings of the chain explained by many biomechanical theories which based on that, the change in the tissue tension-compression in one ring of the muscles chain will lead to changes of the tissue tension-compression leading to bad posture. Some other theories based on the electro myographic activity of the muscles in one ring of the chain which associated with elongation of shorting of the other rings within the muscle chain. Patients with TMD reported to be associated with decrease of the posterior facial height with backward and clock wise rotation of the mandible. This features influence the Craniocervical pos- ture. Patients with TMD and cervical spine problem (upper ring) associated with head moved forward. Normally, the head sit di- rectly over the neck and shoulders, change in the posture with forward head posture lead to a sequence of events. Forward head movement cause strain on the muscle of the neck and shoulders and upper back muscle. This cause decrease of the blood supply of the muscle with muscle fatigue and pain. This movement led to shifting the center of the gravity. As a result, the upper body and back (middle ring) try to compensate by drafting backward. While the hip and lower body (lower ring) moving forward. So, the TMD and neck problem can result in middle and lower back problem, due to loss of balance between the rings of the body chain. High heels are very popular with many women and can be one of the reasons of increasing the incidence of the TMD within the women group of patients. The higher the heel, the more poten- tial damage you can cause to the ankle and foot, by shortening the Achilles tendon that runs behind the heel to the bottom of the foot. This lead to tighten and shortening of the tendon resulting in heel pain. Also, its change the angle of the heel to the toes there- by changing our center of gravity. The Calf muscles contract and adjust to the angle of the high heel and walking with high heel making excessive force within the knee (lower ring). The high heels push the center of the body forward taking the hip and spine put of the normal alignment (middle ring). All of the previously mentioned changes lead to posture alteration which affects the Craniocervical and TMJ muscles (upper ring). This changes the alignment of the hips and spine, (which in- clude our head and neck), predisposing us to back and leg pain or pain anywhere up the chain of linkage. Wearing of sport comfort- able shoes can relief the muscle strain in the lower body (lower ring) with subsequent improvement of the bad posture. The re- sult of improving the bad posture will be reelected on the TMD and the neck (upper ring).