The TMJ or jaw joint is unique and complicated. One feature is that it is comprised of synovial membranes. This is tissue that is comprised of richly supplied blood vessels and nerves. For simplicity, these membranes are separated into four main areas; there are two in the lower TMJ joint cavity and two in the upper TMJ joint cavity.
In general, there are three main functions of these synovial membranes:
1) Lubrication: lubricates the joint surfaces
2) Metabolic: provides nutrients and eliminates waste in the joint
3) Nerve conduction: can recognize pain
These synovial membranes hurt by compression. Often some of these areas hurt when the jaw joint is misaligned and compressed into these membranes. As you might be able to imagine, the compression interferes with lubrication and nourishment of the joint as well as pain. When this continues over time, the repetition can cause inflammatory and degenerative changes.
It is for this reason, when we do TMJ exams, we palpate all four synovial spaces which provides me with an idea of what is causing our patient’s pain. This exam, which includes checking 8 different components of the joints, combined with listening to patient symptoms and a 3D scan of the joints and neck, truly allows us to visualize and to know how to treat this particular case.
Each TMJ case is unique and having an understanding of the joint helps to provide definitive treatment as necessary.