How many times have you arrived at the end of a case history for a patient suffering with either headaches or neck pain and they say, there is one other thing, I also have a “clicky jaw” whenever I eat or open my mouth.
The jaw is an exciting joint to treat. Unlike treating patients suffering with a slipped disc or low back pain, the tempero-mandibular-joint (TMJ) is one which the osteopath can really get hold of and treat the soft tissue structures that support it.
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The jaw is quite a complex joint with some unique features. Take for example the articular disc of the TMJ. The TMJ has an inter-articular disc which separates the joint cavity into two. Not only is the disc's structure special being both concavo-convex superiorly whilst inferiorly it is only concave (thus fitting its joint surfaces exactly), it also is made of fibrocartilage allowing a certain degree of trauma and regeneration. The tempero mandibular joint functions for so many of our daily activities, the most significant of which is eating which requires tremendous leverage and strength
It is the disc that is often the bane of most peoples problems suffering with TMJ pain. It is the structure most likely to be giving the clicking sound that patients hear when chewing. This occurs as a result of disc displacement. The disc can be be displaced at various places along its length and this can interfere with the smooth gliding of the mandible on the articular surface of the temporal bone. The most common problem is for the disc to be displaced medially as a result of the action of the masseter muscle straining and lengthening the lateral TMJ ligaments and allowing excessive medial movement
The TMJ can move in 6 directions:
1)Up and down – the main movement used in biting and chewing
2)Protrusion and retraction – mainly used for tongue movements, talking and swallowing
3)Left and right – for grinding the food when chewing
The muscles that control these movements are:
1)Masseter – this muscle is the main chewing muscle and often becomes tight from emotional stress. It extends from the zygomatic arch to the outer surface of the ramus of the mandible
2)Temporalis muscle – supports the masseter muscle aiding it in chewing and it stabilizes the bite of the TMJ. It is a fan shaped muscle and extends from the surface of the temporal fossa, deep to the zygomatic arch and inserts on to the ramus of the mandible.
3)Lateral and Medial Pterygoid - these 2 muscles are found deep to the ramus of the mandible and they elevate and protrude the mandible.
Observation:
When assessing a patient with TMJ problems the osteopath begins with a standing postural assessment observing head-neck-spine relationships. The osteopath paying special attention to the position of the TMJ in relation to the skull, anterior and posterior cervical soft tissues and shoulder girdles all of which make up the closed kinetic chain of the gnathic system. The osteopath should observe areas of stress in around the TMJ itself including the scalenes, sternocleidomastoid and platysma. Obvious signs of tension or stretching should be noted by the osteopath as they will indicate a stress and potential imbalance of the TMJ and will need to be reassessed during the passive examination.
Active examination should focus on asking the patient to perform movements of the spine specifically the cervical spine noting restricting in movement in any direction which could be related either directly or indirectly to the TMJ via the cervical fascia, infra-hyoid muscles, anterior cervical muscles and posterior cervical muscles.
Active examination should also include examination of the gleno-humeral joints which have a soft-tissue connection to the somato-gnathic system.
Finally one can ask the patient to open the mouth in all directions paying attention to any adventitious movements.
Passive examination:
Palpation by the osteopath of all the structures previously mentioned, however this time the osteopath is able to put his hands directly on the TMJ and ask the patient to open her mouth. This allows the osteopath direct contact with the dysfunctional joint. The osteopath should simultaneously palpate the muscles around the TMJ gathering information about the hypertonia of the soft tissues and any inequality on either side that may be creating an imbalance of movement.
Gentle palpation along the anterior and posterior structures of the cervical spine should include articulation of the hyoid bone, glenoumeral joints, clavicles, menubrio-sternal joints and ribs, all of which have a role to play in the stability of the TMJ function.
Treatment
After a full assessment of the patient's condition the osteopath can start to design a treatment plan. Osteopathically I like to begin treatment distal to the area of pain. After doing a general osteopathic examination and treatment (where necessary) including working as far afield as the feet, ankles, knees and hips I eventually start to focus on structures directly related to the jaw.
Osteopathic treatment will most likely start with the dorsal spine removing any somatic dysfunction that may be reflecting in the cervical spine. Treatment may involve balancing the glenohumeral joints by treating the rotator cuff muscles and muscles of the scapulo-thoracic complex. Any tension in the scapula will be reflected in the cervical spine, anteriorly and posteriorly creating unilateral tension in the TMJ.
Osteopathic treatment of the cervical spine focuses strongly on the sub-occipital muscles and occipito-atalantal articulation onto which many TMJ-related muscles attach indirectly due to their close proximity.
The osteopathic work around the TMJ needs to address the local muscles directly using soft tissue massage to masseter and temporalis and indirectly to the pterygoids using articulation of the jaw or muscle energy.
The osteopath must try to be as clear as possible in which direction the jaw is being pulled so as to treat the appropriate muscles. The theory is that if during opening the mouth the jaw shifts to the right thereis tension in the muscles on that same side. It is important therefore treat the muscles on that side to allow some relaxation of the soft-tissues and for the TMJ to sit equally well in the condyles of both sides. Treatment to masseter can be quite painful so it it good to use gentle inhibition assessing the patients response and not working too aggressively.
The osteopath will most likely need to address the TMJ itself using techniques that temporarily “gap” or separate the two joint surfaces between the the condyle of the mandible and the base of the skull. This gapping allows the joint to reset itself comfortably and also may induce some movement that may have been lost due to excess tension on the restricted side.
At the end of treatment the osteopath should reassess how the movement in the TMJ has changed and whether there is any improved function. This is done by asking the patient to open her mouth and observing any adventitious movement. Often observation is done best when standing at the head of the table with the patient lying supine. Furthermore the osteopath can slide his finger over the joint with his little finger tucked in the joint under the ear lobe. This allows direct contact with the the TMJ as it opens and closes and dysfunction can be easily palpated.
Often patients go back to bad habits of chewing gum or experiencing emotional stress that influences the masseter but awareness of these factors as well as a management plan and gentle stretches can prevent the problem from reoccurring.