I’ve been on a quest lately. I figured I may as well share it with you.
You see I have a patient who has TMJ. She has seen me, she has seen other chiropractors, she has seen massage therapist and yet she still has TMJ.
When she opens her mouth there is a loud click on the left, then right. When she closes it there is another loud click on the left then right.
It frustrates me that collectively we have been unable to help her TMJ resolve.
So I’ve been on a quest to understand TMJ and how to treat it. My goal is to help her get rid of that popping and that pain that she has in her mouth.
Am I there yet?
No, but we are making progress.
The TMJ is a complex joint. There are a lot of professions that have treatment protocols for those with TMD (let’s clear this up first, TMJ is kinda a misnomer. Everyone has a (well two) TMJ’s it simply means temperomandibular joint. When you have pain in the area it is called TMD or temperomandibular disorder).
Massage therapist: yup
Physical therapist: yup
Interestingly, chiropractors have probably the least amount of research on the topic (a theme I’m discovering for other areas of the body as well unfortunately).
So I drew on the latest research (and some not so recent research) in my quest to understand TMD.
The first place to start when you want to understand something is the component parts that make it up. Once you understand what makes up the joint and surrounding areas, you are better prepared to handle potential issues.
So let’s start there.
We are going to take a layered approach, moving our way from the bones, to the muscles and ligaments, to the nerves.
There are two bones that comprise the the TMJ. As you may have guessed there is the temporal bone, and then there is the mandible or the jaw. The mandible has two processes that stick out. We are concerned with the back one, the mandibular head, which is the process that articulates with the temporal bone in what is called the manidbular fossa.
This joint has a hinge component and a glide component to it. If you open your mouth slowly, you will first feel the hinge as it opens, then about half way through you will feel it glide forward.
Now between the mandibular head and the mandibular fossa lies a disc. This disc is very important. It provides cushion so the joint isn’t bone on bone. It helps the jaw hinge and glide smoothly. Also important is what is behind the disc. It is called the retrodiscal tissue. We will come back to that.
Next we have the muscles of the jaw.
The first muscle is the mighty temporalis. This is the one that starts on the side of the head and inserts onto the coronoid process of the mandible. Next we have the powerful masseter. Internally we have the medial and lateral ptyergoids. Of secondary importance you have the posterior digastric and some of the hyoid muscles that help with the TMJ.
The jaw receives nerve supply from the trigeminal nerve. Specifically the auriculotemporal branch of the trigeminal nerve. Perhaps you have heard of someone with trigeminal neuralgia, the jaw could be affected by that.
Ok so now we now the anatomy of the jaw, we can start talking function.
In a normal jaw the masseter, temporalis, and the lateral pterygoid are responsible for closing the jaw. The jaw itself does not need a lot of helping opening, mostly just for these muscles to relax.
As the jaw is opening, it will hinge open and then glide forward. The disc will glide forward with the mandibular head. The retrodiscal tissue occupies the area that the disc had occupied before the jaw was open.
When a person has a clicking in their jaw it is because the disc between the mandibular head and the mandibular fossa is dislocated anteriorly. As the jaw opens and glides forward, the pop is what happens as the mandibular head goes underneath the anteriorly displaced disc. As you close the mouth the pop is coming from the mandibular head sliding off the displaced disc.
Why does this cause pain?
Remember our friend the retrodiscal tissue? Yeah there is something I forgot to tell you. You see the disc itself has no pain receptors. As it is anteriorly displaced it has no issues whatsoever just hanging out there. The retrodiscal tissue on the other hand…that does have pain receptors.
And now this tissue is jammed between the mandibular head and the mandibular fossa. Whenever something is pinched (and it has pain receptors) it creates pain.
Now in the olden days they would actually perform surgery on this jaw. They would open it up and place the disc back in place. What they found is that it wasn’t really helpful. The surgery itself would often times create even more pain, and the disc had a tendency to slip out again. Nowadays they rarely perform surgery.
So how do we take care of the problem?
That’s a great question, and actually one with no definitive solution! One paper I read stated the the disc most often spontaneously moves back into place.
Up to this point most medical practitioners are on the same page, its how to treat the problem where they diverge.
Dentist will say it is due to improper occlusion (or how your teeth sit at rest), they will make you a mouth guard and ask you to wear it at night.
Physical therapist will say that it is due to improper muscle firing and will give you exercises like the Rocabado 6, isometric exercises, and having you practice slooooowly opening your mouth in a straight line in the mirror to help retrain the jaw.
Massage therapist will point out all the muscles that have trigger points that refer up into the TMJ and surrounding regions. They will also work the pterygoids internally in your mouth.
Chiropractors will say that it is a joint dysfunction and will manually adjust your jaw, and usually your neck as well.
Another field I’ve discovered is called myofunctional therapist. They are concerned with how the tongue moves and how the jaw is shaped. They would retrain the tongue to rest in its proper place and give exercises to help strengthen the tongue and make sure it moves properly.
And here’s the kicker…
Anterior disc displacement only accounts for 30%(!!!) of all TMD problems.
30% is joint related (that’s where chiropractors shine)
And the last 40% is muscle related.
I suppose that is why most of the research is on the 30% disc displacement because the other two groups are relatively easy fixes.
So where do I fall on treatment of TMD now?
I used to believe that TMD issues needed to be adjusted and adjusted only. And yet that is the thinking that led to my patient having chronic TMD issues. Now I incorporate elements from every profession (well I can’t make a mouth guard).
Ultimately it is my belief that I am a facilitator. Putting the body in the best position to heal itself is the best thing I can do to help a person.
I can’t spontaneously reduce a patients anteriorly displaced TMJ disc, but I can adjust the joint, and I can work the muscles inside and out, and I can get rid of those trigger points causing referred pain, and I can recommend exercises, and I can refer to a dentist for a mouth guard.
With all those things in place, the body should be in the best position possible to heal itself.