Trigger Point Ablation and TMJ Syndrome
We have all heard this message before and most of us would attest to the validity of this statement. It is with this philosophical message in mind that we present our first clinical report on a product that is not at all representative of high technology. It is not expensive, not technically difficult to use, does not require professional study or a degree as a prerequisite for use and, all in all, has little glamour. It is, I believe, a good current day example of teaching patients how to treat themselves. The device itself is actually quite unimpressive by first appearance and it would be quite natural for many to relegate in the realm of “clinical junk.” I would, however, caution those who might be drawn to this conclusion. The instrument is called the MyoFreeTM (see Figure 1) and is a tool that uses intra-oral ischemic compression (pressure) to obliterate trigger points that can be the source of pain and dysfunction in the jaw and face. This instrument that can be used at home by the patient to treat intra-muscular trigger points (TPs) around the tempero-mandibular joint that often play a role in clinical TMJ syndrome.
Not only is this tool rapidly becoming a popular therapy for pain management, but it is also consistent with the idea that patients can be taught to positively impact their own condition or problem. Home pain management is empowering for patients, and represents responsible medicine as it enlists the notions of shared decision-making while encouraging the patient to be self-directed and take ownership of a chronic problem. Patients thus become active participants in their own care plan. When clinicians are faced with treating recurrent myofascial problems, it makes good sense to provide a treatment regime that is both effective and can be sustained without regular visits to a medical provider. The MyoFree tool appears to be a cost-effective intervention for the treatment of TMJ and oro-facial pain syndromes that have trigger points as the basis for their genesis.
Trigger points were popularized by Travell and Simon1 and figure prominently in their view of craniofacial pain disorders in general. They felt that TPs were the underlying basis for much of the morbidity associated with head, neck and facial pain. In the years subsequent to their treatise, there have been a plethora of scientific and clinical papers pointing to trigger point infestation as either the central cause or significant contributor to painful syndromes and myofascial disorders such as is seen in TMJ.2-4 Figure 2 shows potential trigger point foci in the masseter muscle of the jaw and indicative of where treatment with the MyoFree tool might begin. The hooked nature of the device allows the patient to reach back into the mouth and apply sustained pressure to these points with little effort and training.
The clinical characteristics of a trigger point are that they tend to be hyperirritable spots located in skeletal muscle tissue that, when compressed, cause significant pain and pain referral. The TP feels like a nodule or taut band on palpation. There is a classic “jump sign” that is elicited during vigorous palpation by the examiner which aids in TP verification. These palpable contraction knots or taut bands will ultimately change or alter the muscle tension characteristics of a jaw muscle such as the masseter—leading to secondary problems of internal derangement, arthritis and/or simply faulty joint mechanics leading to ultimate joint erosion and breakdown.5,6
Trigger points are not always the primary cause of a TMJ dysfunction and can develop as a result of another type of problem such as disc deformation/tearing (internal derangement), in which case the TPs would be secondary to internal derangement. Whether primary or secondary entities, the presence of trigger points can perpetuate disability and worsen the prognosis and interfere with primary interventions if they are not considered and treated. It has been well established that although we might be uncertain as to how TPs actually form, we are more certain that they do appear as a sequelae to such things as trauma, faulty posture, repetitive motion, muscle imbalance, disease entities, and debilitation to name a few.7
Trigger Points and TMJ Syndrome
There is strong research evidence to show the correlation between presence of trigger points and resultant TMJ syndrome and/or face/head pain in general.8 As well, when trigger point treatment is included in a care plan for an individual who has TMJ, the outcomes appear to be superior than in those treatment regimes that do not address trigger points in the intervention.9 There appear to be several scenarios in which trigger points become important predisposing, initiating, and/or precipitating factors in TMJ syndrome or dysfunction. Those who primarily treat trigger points for this condition will argue that TPs are involved no matter what the primary diagnosis might be. Trigger points have both a sensory component but also manifest as tension-altering entities which, over time, can lead to uneven bite mechanics and mouth opening restriction —further leading to pathologic mechanical changes in both joint and surrounding soft tissues.10 Furthermore, there could be a direct link between trigger points and trigeminal nerve involvement. Trigger point alterations in muscle (tenderness and sensitization) could conceivably spread to the major nerves servicing the TMJ region.
It is not uncommon for trigger points to be identified as contributing factors and co-existing with internal disc derangement, TMJ synovitis, TMJ arthritis, as well as being the primary pathological entity in myofascial pain syndrome (MPS) of the TMJ.11 In a study involving 300 patients who had all been involved in a motor vehicle accident, the most common clinical findings identified on medical examination were the following; jaw pain, neck pain, post traumatic headache, jaw fatigue, and severe TMJ crepitus or clicking. The most common diagnosis were the following in rank order: masseter muscle trigger points, closing jaw muscle hyperactivity, TMJ synovitis, opening jaw hyperactivity, and advanced disc derangement.12 What we are seeing is that trigger points are an important treatment consideration when formulating a treatment plan for the various diagnoses involving the TMJ, orofacial, and/or head regions of the body.