Addressing the TMJ
by Erik Dalton, Ph.D.
It’s not uncommon to be in the final stages of a history intake when the client casually states, “Oh, there is one other thing — sometimes my jaw clicks when I eat or open my mouth.” According to the TMJ Association, “A clicking jaw in those presenting with face, head and neck pain may be a smoldering fire that should not be ignored.” Joint noise is not unusual, but a clicking jaw can represent an incorrect condyle-disc-mandibular fossa relationship or possibly osteoarthritis (Image 1).
I find it’s best to address jaw-related muscle imbalance patterns before the disc(s) becomes irreversibly deformed. A systematic review by Medlicott and Harris found that active exercise, manual mobilizations and postural training may be effective in treating temporomandibular joint (TMJ) disorders.1 However, many therapists choose not to treat the condition unless the client is experiencing pain. I believe this represents a missed opportunity to address anatomical and functional problems in their early stages.
The disc is vulnerable at various places along its length, but these are the two most common TMJ presentations I see in my practice:
- bilateral condylar jamming secondary to forward head postures (FHP).
- unilateral masseter and temporalis hypertonicity and medial disc displacement due to atlantoaxial (A-A) joint dysfunction.
In Myoskeletal Techniques, we first treat the atlas rotation using suboccipital release techniques such as the one demonstrated in Image 3. Once the atlas on axis fixation is corrected, hypertonic jaw closers such as the masseters, temporalis and medial pterygoids are stretched using a simple gapping technique (Image 4). To confirm the correction was successful, observe for any adventitious movements as the supine client slowly opens and closes the mouth. If the jaw shifts to the left, there’s still left-side muscle “tweaking” to be done.
Is your client’s head on straight?
To assess, draw imaginary lines through the pupils and across the lip with the client standing facing you. If both lines are elevated on the same side, the client typically will have a C1 (atlas) rotation on the high side (Image 2). Due to the convex-convex A-A condylar surfaces, as C1 right rotates, it lifts the right side of the occiput, causing mild compression (occlusion) of the left TMJ. A high right eye on the side of the rotated atlas is often a dead giveaway. Try this on a plastic skeleton.
Jaw closers vs. openers
Clients presenting with FHP are vulnerable to increased jaw stress as tensile forces develop in the hyoid and digastric muscles. To compensate for FHP, the brain pulls the cranium back using jaw-opening muscles such as the infrahyoids and digastrics (Image 5). As recorded in EMG studies, the masseters and temporalis must overwork to close the jaw when the hyoid muscles are tight.2 Travell believed this to be a major cause of trigger points resulting in temporalis headaches and masseter pain.3
Prolonged stomach sleeping with the head turned to the dominant side (usually right) dehydrates the A-A facet joints and may lead to articular cartilage degradation, right-side inferior oblique hypercontraction, and joint fixation. Naturally, the brain won’t allow the person to walk around with the head rotated right, so it activates the multifidi, rotatores and other left cervical rotators to move the head back to a neutral position. Because of the flat plane of the facet joints C2-3 to C7-T1, sidebending and rotation couple to the same side. Therefore, left rotation further left sidebends and compresses the jaw. Teeth grinding may develop in clients with long-term A-A alignment problems.
Sustained hypercontraction in the jaw openers and closers forces the mandible to translate posteriorly, a condition called jaw retrusion. Thus, the battle begins, and the mouth closers usually win—at a terrible cost to the TMJ and neck. Antagonistic co-contraction of these opening and closing muscle groups promotes abnormal mandibular positioning (overbite), nerve compression, ligamentous strain, and disc compression, leading to commonly seen TMJ disorders.
Medlicott M.S., & Harris S.R. (2006). A systematic review of the effectiveness of exercise, manual therapy, relaxation training and biofeedback in the management of temporomandibular disorder. Phys Ther, 86(7), 955–973.
Goldstein, D.F., Kraus, S.L., Williams, W.B., & Glasheen-Wray, M. (1984). Influence of cervical posture on mandibular movement. J Prosthet Dent, 52(3), 421-426.
Travell, J.G., & Simons, D.G. (1983). Myofascial pain and dysfunction: The trigger point manual (Vol. 1) (pp. l71-173). Baltimore, MD: Williams & Wilkins.