Tuesday, June 1, 2021

TMJ and the Neck – What’s the Connection?

One of the most common and troublesome problems is a condition known as Temporomandibular joint dysfuction, or TMD for short. In fact, many of you may have heard someone talk about their TMJ or having TMD, but didn’t quite know what it was.
TMD involves the joint that connects your jaw to your head. Proper movement of this joint is critical to proper function. It has a profound affect on people because dysfunction of that joint can cause a variety of problems including:
  • Sharp/stabbing jaw pain
  • Inability to open the jaw properly
  • Headaches
  • Neck pain
  • Painful clicking
  • Teeth grinding
  • Clenching
  • and much more...
It has rapidly become one of the more common reasons for visits to a neurologist and pain clinics, because of the dramatic impact that this sensitive piece of anatomy has on a person’s quality of life. Many times, this condition is treated with medications. In some cases, muscle relaxers or injections to the joint.

What does this have to do with the neck?

A search of PubMed will show numerous references for increased incidence of TMD in conjunction with a whiplash injury, or head/neck trauma. A systematic review of these papers show that people with whiplash/head injury actually have more severe pain and more pronounced dysfunction of the joint.

Another review showed that just treating the TMJ in these whiplash related cases poor outcomes suggesting that the cause of the problem may be outside the joint itself. The whiplash associated cases showed just a 48% improvement compared to the non-whiplash cases which improved 75% of the time. That leaves a huge amount of people who are still in pain and suffering because the primary insult to the body was not addressed properly.

TMD usually comes in 2 varieties:

1. Muscular dysfunction – the muscles of the jaw (pterygoids, masseter, temporalis) become hypertonic and dysfunctional creating painful musculature and sloppy movement.

2. Articular dysfunction – the joint itself can have problems. Dislodging of the disc, arthritic degeneration, and inflammation can irritate the very sensitive nerve endings that cover the joint.

Not much can be done about arthritic breakdown of a joint. However, this is a less common cause of TMD. The most common causes of TMJ problems stem from muscular imbalance and dislodging of the articular disc. In a way, these two problems are intimately related. When you have bad jaw muscles moving the jaw abnormally, then it leaves more room for the articular disc to shift out of place.

So what can make these jaw muscles dysfunctional? To know that, we have to know what controls the muscle. Every muscle in your body is controlled by a nerve. Whether it be a big bulky bicep, an achy sore back muscle, the blood pumping heart muscle, and the food digesting stomach.

For the jaw muscles, a special nerve called the Trigeminal Nerve emanates from the skull and provides innervation for the face, jaw muscles, teeth, brain, and other important structures. (as seen in the above image)

The trigeminal nerve is one of twelve specialized nerves called Cranial Nerves. The unique thing about Cranial Nerves is that they do not exit out of the spine. They actually begin come out of the brain and the brainstem, and exit out of the skull. Therefore, a problem with one of the cranial nerves is usually indicative of a problem at the brain stem.

Cervical Displacement, Whiplash, and the Brain Stem

One of the reasons that our office gets referrals is because of how Cervical Displacement impacts the health and function of the brain stem. While the top of the neck doesn’t apply direct pressure to the brain stem, the movement and function of the neck has large implications for this important piece of anatomy.

When someone has an episode of whiplash, there can be substantial damage and injury to the neck, but the more concerning portion is what happens to the nervous system. A phenomenon known as Central Sensitization occurs. This problem happens when the brain stem fires inappropriately to the limbic system (controls the basic emotions (fear, pleasure, anger) and drives (hunger, sex, dominance, care of offspring)) and reticular activating system (the places where pain is interpreted in the brain). When this happens, even the slightest touch or movement can trigger a pain sensation in the brain.

This is why many doctors can find no physical damage to the body, but people will suffer with chronic pain issues like fibromyalgia. People recognize this quickly when the pain is stemming from the neck, shoulders or back, but the reality is that this same thing is happening in the jaw muscles.

To get to the root of someone’s problems, we have to evaluate this critical, but under studied part of the nervous system. 

How does Structural Chiropractic address this?

1. Restore healthy biomechanics to the spine – create a state of Normal Structure in the neck so that the proper signals get to the brain.

2. Increase circulation through the brain – proper alignment ensures that blood to and from the brain stem properly. Proper blood flow means better nerve firing.

3. Restore health biomechanics to the jaw – Once the neck alignment is restored, most of the time the jaw will reset on it’s own. However, sometimes gentle jaw adjustments may be necessary.