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.