Joint related pain may occasionally result from inflammation, as in rheumatoid arthritis, but more usually from degeneration of the tissues within the TMJ. This wear and tear in the joint, and dislocation of the meniscus are the two most common joint disorders of the TMJ.
Note two things here. How the condyle (posterior prong) sits in its fossa, and the position of the normal disc. See how the disc is attached another very important muscle, the lateral pterygoid? Because of this attachment to the disc, this muscle can become supremely, exquisitely, extremely painful.This is the muscle that opens the jaw, pulling the condyle forwards out of its fossa, protected by the disc from grinding bone on bone. Used on one side only, it moves the jaw from side to side when chewing the cud. Juggle your jaw from side to side - that's the Lateral Pterygoid you are using. Now protrude the jaw, push it forwards. That's the two Lateral Pterygoids working together. See in the next picture how the condyle has slid forwards out of its fossa? That's normal.
Dislocated disc (meniscus)
Notice in the next picture how the disc has been displaced forwards. This is definitely not normal. Should you now open your jaw there will be a popping sound as the disc pops back behind the prong of the jawbone (the condyle). When this happens repeatedly the disc starts to wear, and sets up a pain pattern in the muscles around the jaw joint.
Try placing the pads of your index fingers in your ear, and slowly open your mouth. Do they open nicely together? Any clicks or pops?
Often patients are terrified of words like disease and degeneration sometimes used in describing this wear-and-tear process. No need, it's no different to your hair turning grey. What is now clearly recognised in the literature though is that, untreated, joint malfunctions, or fixations as we call them, lead to unnecessary, premature degeneration. Every time the displaced disc has to pop over the condyle, it is probably equivalent in terms of wear and tear to 100 openings of a healthy jaw.
This information is then fed back to the brain via the largest cranial nerve, the Trigeminal nerve which supplies the face and has a spinal nucleus deep in the neck. This is how the pain from a clicking jaw causes facial pain, and can be referred to the neck.
See that long black structure in the picture below? (in the next pic it's highlighted in green). That is the huge trigeminal nucleus extending right down into the spinal cord in the neck.
It's called the TRI-geminal nerve, because it has three different sensory branches, seen here in green, blue and brown, supplying primarily the face, teeth, sinuses and TMJ. It is by far the largest cranial nerve.
Whilst I don't want to overdo the complexity of TMJ anatomy, this next slide will show you how the TMJ can cause neck pain, perhaps CAUSE subluxations, and how subluxations in the cervical spine can make the TMJ vulnerable to injury.
On the right hand side you have the four functions of the Trigeminal nerve. Focus only on the one labelled "Pain and Temperature". If you follow it along the "Spinal Trigeminal Tract" you will see that its sensory nucleus (called the "Spinal Trigeminal nucleus") is right down in the neck. From there the dark tract reaches up into the sensory cortex of the brain (those two dark arrows)where the pain is perceived.
So noxious pain and temperature signals from the TMJ feed right down into the neck, where they meet up with other nerves from the neck, swapping messages. Pain!
Enough, right! Well done, you're a perseverer!
There's nothing simple about the human body. Nothing! and certainly not the TMJ anatomy. "Fearfully and wonderfully made" as one great surgeon named his book. Amen!I said there are four jaw muscles. The fourth, the Internal Pterygoid is also a jaw closer. I include it here, partly for completeness, but also so that you can see the four branches of the Trigeminal nerve in situ. One motor branch to the muscles of the jaw, and three sensory nerves. See the proximity of the nerve to the Internal Pterygoid muscle? This is why jaw muscle pain can so readily become intense nerve pain.
TREATMENT
Like all other chronic joint conditions there is no real permanent ‘cure’ for TMJ anatomy wear-and-tear. An acute pain or click which has just begun, correctly addressed should pass over, and the trick is not to allow it become chronic. Like any other condition, once you know it's not going to get better on its own, then it's better to contact the relevant health professional sooner rather than later. Not unlike neck and back pain, good care of chronic TMJ pain aims at reducing the pain, restoring normal function, and avoiding the known no-no’s. Like biting a whole apple and chewing gum.
The pain and dysfunction is often temporary, lasting a few days or weeks, even a month or two perhaps, so adventurous surgery which cannot be reversed should only be contemplated when all else has failed. Your first port of call, of course! should be your chiropractor.
I have done no research in my practice, but I would guess at least 75% of patients have good to very-good results with chiropractic treatment of the TMJ.
What will your chiropractor do? Firstly a good history of how the pain or clicking started, how long it's been there, what aggravates it etc. Whether you are getting headaches, and any of the sharp stabbing pain associated with Trigeminal Neuralgia. Then there will be an examination of the TMJ anatomy, and your neck. Treatment will include mobilising the joint, treating any active trigger points in the muscles, and stretching of the muscles and the joint capsule.
The good news? There is a a very treatable condition. You don't live with TMJ anatomy pain for month after month. The bad news? If the pterygoids have active trigger points, they can only be reached from inside the mouth, and the treatment may be wretchedly painful, sometimes lasting a few days. Hang in with your chiroprator, that pain too will pass. This treatment is very effective.
What can you do for yourself? An iceblock rubbed directly on the painful spot, followed by moist heat (Tip: do it in the shower) will help. Now that you've taken your TMJ anatomy tour, you know where to find these muscles, right? Gently massage them. Your chiropractor will give you some stretches and, for more tips about exercises,
click here.
If appropriate, they may adjust your neck too, if there are associated fixations. For more about the neck adjustments,
click here.
For an interesting case from the Coalface, click on this link and
scroll down to Mrs Hol.
Migraine
Interestingly, research shows that migraine sufferers, clench their Temporalis muscles 14x more often whilst they are asleep than normal people. The reasons for this are complex, but without a doubt, TMJ anatomy has some of the answers.The aim in migraine prevention is to limit the amount of negative sensory input (that is, to limit your migraine "triggers") to that huge Trigeminal Sensory Nucleus. Even cold draughts to the face can be perceived as noxious stimuli to the face, but certainly too much yacking, chewing, heavy massage of the muscles, and over stretching of the jaw. Stress and conflict too, which may cause grinding and gnashing of the teeth.
This sets up a pattern where the sensory Trigeminal nucleus starts to bombard both it's own motor nucleus, causing the jaw muscles to contract, especially while you are asleep, and those in the neck.
It may also bombard other cranial nuclei which are found close by, causing nausea, pulsating arteries, dizziness and senstivity to light and sound, and pain in the neck.
Bruxism, or grinding your teeth we will consider on another page.
Medically the diagnosis of Migraine is made on the following basis:
"Therefore, when a patient reports an intense pulsating headache lasting at least 4 hours, accompanied by either nausea, photophobia or phonophobia; their daily activities are limited; and all diagnostic tests are within normal limits, then the diagnosis is migraine."
It causes in the USA a staggering 17 billion dollars in lost productivity alone.In summary, TMJ anatomy encompasses a huge area involving your chiropractor. Face pain, neck pain, headache. It's very complex, and I'm not suggesting that Chiropractic has the whole, and simple answer. Clearly, nobody to date has all the answers, or even the majority of them. We live in a stressed society, which eats junk, chews gum, has motor accidents. We slap each other around so blows to the face and jaw are common. The result? Pain. Chiropractic has a large role to play, but your doctor, dentist, psychologist, minister and marriage counsellor should all be considered. And the oro-facial surgeon should be your last port of call.
For more information about the jaw,
go from TMJ anatomy to TMJ ear pain.
Links
Now is the time to take that Henry Gray tour.
