The TMJ, or the temporo-mandibular joint, is one of the most important joints in the human body, yet one of the most overlooked.
It is located just in front of your ears, one on each side. It connects your lower jaw (mandible) to your skull. Every time we talk, chew, or yawn, our TMJs work. Despite its frequent use, most people don’t think about it until something goes wrong. Whenever there is TMJ pain or dysfunction, it can interfere with simple tasks like eating or even talking.
Fortunately, allied health practitioners such as physiotherapists and osteopaths are available to offer a variety of ways to manage and treat TMJ disorders.
TMJ anatomy:
A joint is where two bones meet and unlike most joints in the body that are covered by smooth hyaline cartilage, the TMJ depends on thicker fibrocartilage so it can handle the heavy stress from actions like chewing and grinding.
Articular disc: The TMJ has an articular disc made of fibrocartilage, which divides the joint into two compartments - the superior compartment above the disc and inferior compartment below the disc.
Superior (upper) compartment: This part is responsible for translational movements, like the sliding or gliding motions that occur when the jaw moves forward or side to side
Inferior (lower) compartment: This compartment handles the rotational, hinge-like movements, which allow you to open and close your mouth.
Ligaments: Surrounding the TMJ are ligaments that provide stability. Ligaments are thick connective tissues that help hold bones together.
Mechanics of the TMJ:
The lower part of the jaw is called the mandible. Mandibular movement occurs thanks to the TMJ and its associated muscles. Movements consist of both rotation and translation.
Rotation occurs at the initial phase of mouth opening in the lower compartment of the TMJ. Translation is a motion that occurs during the latter phase facilitated by the structure of the upper compartment of the TMJ.
These movements allow for a full range of mouth functions, including opening, closing, and subtle sideways motions. Coordinated activity of muscles like the lateral pterygoid for opening, temporalis, masseter, and medial pterygoid for closing, ensures smooth jaw movement.
TMJ disorders encompass a range of conditions that can be triggered by several factors, including muscle tension, stress, trauma, arthritis, or jaw misalignment.
Causes:
Muscle Tension: Prolonged stress or anxiety may cause the muscles around the jaw to tighten
Teeth Grinding or Clenching: Many people unknowingly grind or clench their teeth, especially at night. This is also known as bruxism, which increases stress on the TMJ
Trauma: A blow to the jaw, whiplash, or other injuries can cause the TMJ to become misaligned or inflamed
Arthritis: Conditions like osteoarthritis can lead to degeneration of the joint over time
Symptoms:
Pain: This can be localised to the TMJ, or radiate to the lower jaw, teeth, temple, neck, face, or even to the ears
Restricted jaw movement: Difficulty and/or pain opening or closing the mouth fully
Clicking or popping sounds: These noises often occur when the joint is misaligned, or the disc is displaced
Headaches or neck pain: Tension headaches or tightness in the neck and shoulders are commonly associated
The differential diagnosis of temporo-mandibular joint disorders involves considering other conditions that can present with similar symptoms, such as jaw pain, headaches, or restricted jaw movement. It’s important to rule out these conditions to ensure accurate diagnosis and appropriate management. Conditions that need to be considered include things that affect teeth, the neck, the sinuses, the ears, and nerve disorders.
How to differentiate TMJ disorders from other conditions:
Clinical history: Questions will focus on the onset and type of pain, activities that aggravate or relieve symptoms, and identifying symptoms in other areas such as headaches or the ear
Physical exam: A thorough physical examination will include palpation, range of motion assessment, and special tests to help identify TMJ involvement, or not
Imaging: In cases of suspected fractures or arthritis, imaging such as X-rays, MRI, or CT scans may be used and will involve a GP or specialist to do so
Referral for further evaluation: If the clinical signs point to an alternative diagnosis, e.g. trigeminal neuralgia or sinusitis, referral to a GP, dentist, or specialist may be necessary
When dealing with TMJ disorders, intervention provided by physiotherapists and osteopaths with specific training, can be one of the most effective approaches to help relieve pain and restore function.
Assessment:
A therapist will begin by taking a thorough history of symptoms, including the nature of pain, when it started, and any triggers. Questions will be asked about lifestyle such as stress levels, and if any bruxism exists. What follows is an examination of posture, jaw alignment, and range of motion.
Diagnostic Movements and Measurements
Mouth Opening: Normal range is 35-55 mm
Lateral Deviation (sideways motion): Normal range is 10-15 mm
Protrusion and Retrusion: Protrusion is movement of the lower jaw forward and normally is greater than 7 mm, retrusion is the opposite motion and normally ranges between 1 and 3 mm.
TMJ disorders often involve disc displacement, which progresses through four stages:
Stage 1 Early: Mild jaw discomfort and difficulty in jaw movement, occasional clicking or popping when chewing
Stage 2 Mild: Frequent jaw clicking, moderate pain, limited ability to open or close the mouth
Stage 3 Moderate: Jaw locking or dislocation, difficulty chewing or speaking, moderate and chronic pain around the jaw and ears
Stage 4 Severe: Chronic, debilitating pain (or sometimes limited pain), jaw dislocation and inability to open or close the mouth fully, significant impact on quality of life, including trouble eating, speaking, and sleeping
Treatment techniques
Manual therapy: Physiotherapists and Osteopaths use gentle joint mobilisations to help restore normal movement of the TMJ. Soft tissue techniques may also be used to relax tense muscles and relieve pain.
Dry needling or acupuncture: to mange pain and relieve tight muscles
Exercise therapy: Specific exercises are prescribed to help improve jaw mobility, strengthen muscles, and reduce tension. Examples include:
Jaw opening exercises to increase range of motion
Resisted jaw movements to strengthen the muscles controlling the TMJ
Stretching exercises to help with muscle tightness around the jaw and neck
Postural Training: Poor posture can contribute to TMJ pain, especially if you have forward head posture or slouching.
Stress Management: Relaxation techniques like deep breathing, mindfulness, or progressive muscle relaxation can help reduce the muscle tension often associated with TMJ disorders.
Heat and cold therapy: Applying heat can relax muscles and increase tissue extensibility, while cold therapy can reduce inflammation and pain
Pharmacological Treatment: Medications such as analgesics, anti-inflammatory drugs, muscle relaxants, and neuro-modulating drugs for chronic pain may be used.
Surgical Options: Surgery is considered for severe cases, including procedures like arthrocentesis (needle aspiration of fluid), disc repositioning, or total joint replacement.
In situations where other conditions are appear to be masquerading as TMJ dysfunction such as neck disorders, physical therapists are perfectly placed to treat them with manual/hands-on therapies, acupuncture or dry needling, exercise and education. Very often both the TMJ and adjacent regions need to be treated.
It's important to consult with a physiotherapist or osteopath trained in TMJ disorders to get a personalised treatment plan based on your specific condition and symptoms. They can guide you through the appropriate exercises and techniques to manage your condition effectively.
It is also important to seek assessment if you experience any of the following symptoms:
Persistent pain: If your jaw pain lasts for more than a few days and doesn’t improve with rest or over-the-counter pain medication
Difficulty opening or closing your mouth: Limited jaw movement may be a sign of a mechanical problem with the join
Clicking, popping, or locking: Sounds or difficulty when opening or closing your mouth may suggest disc displacement
Headaches or neck pain: TMJ dysfunction is often linked to headaches or neck discomfort, which physical therapists can help treat
Early intervention can prevent the condition from worsening and improve the overall function of the joint.
Our TMJs play a vital role in daily activities, and when something goes wrong, it can significantly impact quality of life. However, with the right approach, conservative therapy can help alleviate pain, improve jaw function, and prevent long-term issues.
If you experience any symptoms of TMJ dysfunction, don’t wait for them to get worse. Consult with a therapist who can tailor a treatment plan that works for you. And remember, your TMJ health is key to overall well-being, so make sure you are taking care of it!
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