A number of people have asked me lately to explain what it means to have medially displaced discs that ‘do not reduce on opening’. OK, let’s break it down folks. The disc refers to the articular disc which is the cartilage like stuff that covers the top of the jaw bone and moves around with the jaw bone during normal functioning. That little disc can easily be displaced when someone experiences trauma- i.e. an accident, birth trauma, or even a slap on the face will quite literally ‘pop’ the disc off the top of the jaw bone.
There are three types of ways in which that little disc can slip off the top of the jaw bone- either forward (it’s called anterior displacement), or outwards (lateral displacement), or even inwards (this is called medial displacement). Well folks, it’s the medial displacement that is the hardest to fix or ‘unwind’ as I call it. The reason for this is that the disc is often just plain stuck inwardly and jammed into all the tissue in that area – and when it is jammed like that, it can pinch the nerves and blood vessels in the area and wreak havoc- i.e. pain, and it is our belief this is one of the causes of tics and tremors. You see, when the disc in the TMJ (temporomandibular joint) is medially displaced, it will pinch or put pressure on the nerves in that area and this can cause all the pain, the headaches, the neck aches, and even tremors and tics. It’s really a bad situation sometimes. And to make it even worse, even if you wear our device to take the pressure off the joint, it may not be enough of an effort to allow the disc to release and come back up into place. It’s like the french fry that’s stuck between the driver’s seat and the center console in your car- you know the one that your kids dropped down there two years ago? That french fry is like a medially displaced disc- it’s stuck way down in there and after all this time it may be so fused to the console that you would have to scrape it off surgically! In other words, even if you pull back the car seat, stretch it away from the center console, pull everything aside, that darned french fry might still be stuck down in there and remain an irritant for a long time to come. This is what it means to have a medially displaced articular disc that does not reduce (go back into place) upon opening your mouth. If the french fry (disc) was down the lateral side of the driver’s seat – i.e. where the chair controls are- it would be easier to get back into place since there is less stuff to get stuck into.
This is the reason why I tell our patients that if the stick test does not work, or if the appliance does not make a difference in the tics over time, this means that the discs are likely stuck off to the side and not able to move. This is more likely over time- in other words, the younger the patient the more likely it is that we can release that disc and get it back into place. The older patients are the ones that are more likely to need the surgery to pick that disc up and put it back into place where it belongs.
For all these reasons, hopefully you can understand why it is impossible to predict the course of the treatment and even more difficult to predict what degree of success can be achieved- if any. I chose to write about this today because I am seeing more and more patients who have severe displacements at younger and younger ages. My hope is to spread the word about TMJ disorder so that people will take it more seriously and start to treat the problem at a younger age, long before there is a need for surgery and extensive treatment!