Bilateral TMJ MRI

Anatomy of the Temporomandibular Joint



A healthy & "Normal" TJM.



Understanding the anatomy of the temporomandibular joint is essential to understanding the problems which can occur and their treatment.

The joint depression in the skull, which lies just in front of the ear, is known as the fossa. The rounded part of the lower jaw, which extends up into the joint, is known as the condyle. Both the condyle and the fossa are covered with a layer of smooth cartilage, which is kept moist by joint fluid. Between the condyle and the fossa lies a very important structure, known as the disc. The disc functions to cushion the force between the condyle and the fossa and assist them in their movement. The disc is composed of a specialized type of cartilage, known as fibrocartilage, which is very unique. Unlike many joints of the body which produce one type of movement, the temporomandibular joint functions through both a rotational or hinge-type movement, and also in translational or sliding type of movement. Translation is necessary for the jaw to move forward, slide side-to-side, and to open widely. Abnormalities of the disc, which restricts translational movement, causes pain or restriction of these movements. The entire joint is enclosed in a soft tissue envelope known as a capsule.




TMJ DISC DISLOCATION:



Normally the disc follows the condyl with mouth opening and moves forward with opening. Disc dislocation is usually anterior with associated perforation of the posterior disc attachment. The condyl impinges directly on the posterior disc neurovascular bundle causing pain on opening the mouth. In anterior dislocation, the posterior band (which is thicker) gets deformed. 70% of pts with meniscal problems have subluxation or dislocation. So in summary;

subluxed tmj disk: looks normal with open mouth and remains anteriorly displaced with closed mouth.

Dislocated: more anteriorly displaced with open mouth. Does not look normal. With closed mouth, the disk remains anteriorly displaced.

In rare cases, the disc would stay in front of the condyle and so would not allow the jaw to be opened very far. Such a condition is called a closed lock of the TM Joint.


What does all this mean?

Symmetrical anterior dislocation of menisci of both TJM's without reduction demonstrated

This is Raven's MRI results. Where as the majority of TMJ is usually one sided, meaning you either have it to the left or right side joints, I have dislocation on both sides.

There is no damage done to the actual joints, both fossa, condyles and joint spaces are in all in good condition. But those blasted little menisci are the culprits. Now reading up on treatment(s), all include the wearing of a splint.



I've done this. Many, many times: Once I was even required to wear it 24/7 for two years before it was concluded it was no longer doing any help. Wearning off it was agony. I still have a splint that I wear on occassion at night or when my face simply hurts too much but I can't speak with it in place and it's uncomfortable. I've also done massage therapthy, ice packs, heat packs, TENS machine, spray and streach, acupunture and PT for this condition. What more is there to do? I doubt it can even be considered a "Serious" condition to warrant surgery which I don't know that I'd do because further research has shown that TMJ surgery is rarely sucessful. So what? More splints for the rest of my life? Which after reading more and new sites tonight on TMJ, can actually aid in the derterioration of the fossa. Meh.

My Neurologist and my PCP are trying to find a TMJ specialist that will work with me. Although my neurologist says she'll still give me the Botox injections for pain management but that is still a month away. So once again it's wait, wait, wait and deal with the pain.

I really don't know how to feel about this any more. Its hard not to feel depressed about this.