Definition of the Temporomandibular Joint and Temporomandibular Joint Disorder
The temporomandibular joint (TMJ) is a freely moveable (diathrodial) articulation between the condyle of the mandible and the temporal bone. It is unique because it is a true synovial joint and, therefore, has much in common with the other synovial joints of the body. It does, however, possess certain unique developmental, anatomical, and functional characteristics which distinguish it from other joints of this type. As with any other joint that we talk about, I think it is important that we understand the anatomy and physiology. I am hoping that you have a little background in this. When I was in physical therapy school, 24 years ago, we had probably an hour of the anatomy of the TMJ. When I started teaching it in the colleges, they actually gave me an afternoon of four hours and maybe another couple hours of lab. I think it is improving, but I do want to tell you also that this is a commonly sought out CE. I think people are lacking in some of the knowledge of anatomy and physiology, as well as the treatment of what to do with this joint. However, as we will discuss later, I think it is pivotal that we are able to evaluate this and treat it for our headache and neck patients and the overall health of the people that we work with.
Temporomandibular joint disorder is a disorder of the temporomandibular joint(s) that causes pain, usually in front of the ear(s), sometimes in the form of a headache. Pain in the TMJ can be due to trauma, such as a blow to the face; inflammatory or degenerative arthritis; poor dental work; or structural defects that push the mandible back towards the ears whenever the patient chews or swallows. Grinding or clenching the teeth due to stress is a frequent culprit. Sometimes muscles around the TMJ used for chewing can go into spasm causing head and neck pain and difficulty opening the mouth. Treatment depends on the cause and severity of the problem and can range from a mouth guard or medication to prevent nighttime tooth-grinding to surgery (from Medicine Net.com). I am hoping that as more physical therapists become educated in how to treat this, that they would add physical therapy to the list.
Just backtracking a bit, my journey in treating TMJ began when my sister was diagnosed with TMJ problems, and she was headed for surgery before she had any physical therapy. This was in the early 1990’s, so I began doing some research to figure out what could be done for her before the surgery. Then I began taking classes starting with the Rocabado, then Paris classes, strain/counter strain with the Jones Institute, craniosacral classes with Upledger, and then the TMD mini-residency at the University of Minnesota. I know there are people out there treating TMD, and I am hoping that, as you will see when we discuss the prevalence and incidence of TMJ, there will be more and more of you interested in pursuing further studies. My goal again today is also that you will be comfortable starting to treat this even from a little bit of the information that I am giving you today.
The Uniqueness of the TMJ
As I said, the joint is unique and not just anatomically. One way is in the way that we use it. When you think about the jaw, we use it for speaking, mastication (chewing), swallowing, facial expressions, musical instruments, kissing, yawning, laughing, and smiling. A lot of these activities are social. It is important to keep this in mind as oftentimes when patients come in, they may also be depressed or have difficulty going out for social activities. They may also be losing weight because they cannot eat. This is a part of physical therapy treatment that is different perhaps than other diagnoses such as ankle problems or back problems. This has a lot to do with how people express themselves.
TMD is also unique in that it influences both sides of the body. I hope that this will make sense to you as we move on with the anatomy/physiology and treatment. We always have to treat both sides of the body, so both jaws will need to be looked at. Oftentimes the problem may be in the non-sore side.
A variety of professionals do treat TMD. You will run into many dentists who treat it using mouth guards and mouth splints. I would strongly encourage you to seek out these professionals. We are going to talk about how we can treat this as a team and how we can make a joined effort to treat these people.
The symptoms of TMD are also very unique. Here are the symptoms that I am talking about:
· Biting or chewing difficulty or discomfort
· Clicking, popping, or grating sound when opening or closing the mouth
· Dull, aching pain in the face
· Hearing loss
· Jaw pain or tenderness of the jaw
· Reduced ability to open or close the mouth
· Neck or shoulder pain
· Eye pain
· Difficulty swallowing
· Blurred vision
· Teeth malalignment
These symptoms are those of the typical patient that comes through your door. I want you to understand that some of these symptoms can be caused by pain in the jaw. Many of my TMJ patients that came into my clinic were very frustrated. Many times they were sent to a psychologist or a neurologist. Many times their symptoms were disregarded. When they came to me and gave me their subjective history, I began looking at their jaw and noting that their dizziness or eye pain can come from their jaw. They were relieved because no one had been able to give them answer like that. Once we get through the anatomy portion of this presentation, the relationships will make sense.
Occurrence of TMD
The occurrence and prevalence of TMD are high. There was a time when TMJ was in the news a lot. When popular celebrities have TMJ and then have their problems cured, we hear about it more. One research article I read said 75% of the population has one sign of TMD, and 33% of the population has a symptom that would cause them to seek treatment. The other thing to note is that women between the ages of 20 to 40 are 3 times more likely to have jaw problems than anyone else. They are not sure why this is. I have a couple theories regarding this, but no one is absolutely sure. When you look at the ages of 20-40, they are the child-bearing years and change in hormone years. They are also very active years where women are more stressed. They are possibly trying to raise a family and work at the same time.
Also, when we look at the joint itself, we see that women do not have strong enough bones. This could be due to joint structure. I had earlier mentioned my sister, and she will come up again as we talk further. She is now in her 50’s, and interestingly enough, her jaw pain is lessening. I am finding that there is an age, usually when you get into your 50’s, where TMJ problems kind of burn themselves out. The older populations who have arthritis usually have more of a movement problem than a pain problem. I find it interesting wondering what all the biomechanics and biochemistry of that could be.
I think TMD is also on the rise because people are using computers more. It could also be because dentists are becoming more aware of symptoms as well. Continuing education of the jaw is one of the most common dental CE courses. That is to our advantage because they are an entry point, many times, for these patients. If you can find a dentist who will refer to you, and you can refer back and forth, it is a great referral source. I have had that relationship in a couple of the locations that I have worked.
We also have to admit with everything going on, that there are increased stresses. One of the ways people show their stress is by clenching their jaw or by holding tension in their neck. This can be related to the problem as well.
Professionals Involved with TMD
For the treatment of TMD, primary referrals come from dentists; oral surgeons; orthodontists; doctors; psychologists; neurologists; and ear, nose and throat specialists. The ENTs are an interesting group which we will talk about as we move along. I would love to get more referrals from them because there are a lot of ear symptoms that have to do with jaw pain as well. They are easy to rule out to tell if they are jaw problems or not.
The people who treat TMD are physical therapists; dentists who treat with mouthguards; doctors giving medication such as muscle relaxers; psychologists offer help with stress reduction and biofeedback; and chiropractors.
History of TMJ and TMD
TMJ/TMD has not been an official diagnosis for very long. It has come a long way though. In 1954, the temporomandibular joint pain dysfunction syndrome was entered into the dental literature as a spasm of the masticatory muscles. I think this was a nice advancement because, in the past, it was actually diagnosed as an arthritic condition, which it can be, but also as a vitamin deficiency or endocrine disorder. You can tell that those types of diagnoses are much different than the musculoskeletal diagnosis that we use. I am not saying these things are not involved with it, but I am glad they have come around to more of a musculoskeletal definition for us.
Clinical Symptoms of TMD
Throughout the rest of the presentation, we are going to dive into the clinical symptoms of TMD. We are going to talk about acute muscle disorders, disk interference disorders, inflammatory disorders, and chronic mandibular hypomobilities. We are not going to talk about the growth disorders. Those are genetic and are things that we cannot control. We can control some of the pain caused from them, but we cannot control the cause of the growth disorders. We will concentrate instead on the muscles, the disc, the joint, and the capsule.
Anatomy of the TMJ
Let’s get started with the anatomy. Like anything else we do in physical therapy, it is important to know what normal is so that we can compare that to what we see in a patient. It is especially important for our TMJ patients because as you notice the symptoms, they are not always clear. They have a lot of referral patterns. Headaches can be hard to describe for the patient. It is important for us to know what feels normal, what looks normal, and what normal measurements are so we can use our objectivity along with their subjectivity to come up with an assessment.