Is Your jaw popping? Locking? Grinding? Or does it just hurt?
Can't eat without jaw pain? "Tight" face? Can't focus because jaw pain?
You May Have TMJ
Sometimes it is due to trauma, such as a fall, car accident or blow to the face. But I’ve found the majority seemingly come out of no where. Yawning, eating an apple, or just waking up in the morning.
Often these issues are also associated with neck pain, stiffness, headaches and migraines too.
TMJ - An Overview of Our Current Understanding
First, let's review the current understanding of what TMD actually is.
According to the International Association for the Study of Pain, temporomandibular joint dysfunction refers to “aching in the muscles of mastication, sometimes with occasional brief severe pain on chewing, often associated with restricted jaw movement and clicking or popping sounds”.
It is thought to occur in 50 to 70% of people, making temporomandibular dysfunction (TMD) a common problem! Fortunately, it is a frequent presentation to my practice that responds well to hands-on treatment!
Also interestingly, It is known that patients who report TMJ pain are also likely to have pain in several other locations, as demonstrated in a study by Spilia (2011). This highlights the likelihood that functional impairments in central nervous system function play a big role in TMD.
Why does the jaw become painful, pop and grind?
There have been many subclassifications of TMJ in the medical research. These include:
• Myofascial syndrome
• Joint effusion
• Internal derangement
• Osteoarthritis (early)
• Osteoarthritis (late)
• Disc displacement with reduction (DDR)
• Disc displacement without reduction (DDNR)
These issues can all contribute to causing popping, locking, or grinding.
Do you need imaging to diagnose and treat TMJ?
While MRI is the best method to identify the anatomy of the jaw, it is not useful for identifying FUNCTIONAL issues. And the function of your jaw is what is important.
And on a practical level, it all boils down to 3 main causes of TMJ pain.
- The Disc
- The joint
- The muscles
1) The Disc- what is the disc?
The disc is an important structure in the jaw. It allows for a normal relationship between the jaw bone (mandible), and the bone in your skull that it attaches to (temporal bone)!
If the disc slips off during movement, this is what we call ‘disc displacement’. If it slips back onto the mandible, we call that ‘reduction’. Disc displacement with reduction is often what is responsible for the very brief clicking that occurs during opening and closing of the jaw.
If the disc does not slip back onto the jaw, this is called disc displacement without reduction, often no click is heard.
This is what can cause locking of your jaw. The disc stops the jaw from being able to move normally, causing the ‘locking’. Unfortunately when this happens, it is oftentimes also associated with muscular spasms, and a lot of pain.
It is very important to note, DO NOT try to force your jaw open or closed if it is locked. You could do serious injury and damage to your disc and other TMJ structures.
2) The Joint
If there are arthritic changes in the jaw, this is often times associated with a grinding sound when moving your jaw. This sound is called ‘crepitation’. Typically sounds like grinding or sand paper rubbing.
This sound can be louder or quieter. It is often, but not always associated with pain and swelling of the joint. It would not be uncommon to have a synovitis of the joint in this scenario.
Likewise it will often times be associated with muscular spasms of the TMJ muscles.
3) The TMJ Muscles
Muscle pain, also called myofascial pain, is thought be one of the leading causes of jaw pain and TMJ. It will also limit jaw movement, and many times I’ve seen it cause a very tight face sensation.
I’ve even had some people with ‘bad’ TMJ say they felt like they needed to rip their face off’! Yes, it can be that bad!
While this explanation is overly simplistic, there are 4 basic TMJ muscles that can cause pain.
- The masseter. This is the muscle that most people think of when thinking of their jaw muscles. It’s the one that is on your jaw bone, that bulges out when you chew. It is the strongest muscle in your body for its size. It’s responsible primarily for closing your jaw
- Temporalis- this is a broad and flat muscle that attaches to the jaw and runs along the side of your head, your temples. Often when this muscle is in spasm it will cause a headache by your temples. It is responsible primarily for closing your jaw
- Medial Pterygoid- This muscle attaches from a bone on the bottom of your skull, to the inside of the jaw bone. It is primarily responsible for closing the jaw.
- Lateral Pteryigoid- This muscle also attaches from a bone on the bottom of you skull. One of its muscle bellies then travels to the inside bone of your jaw, AND the other attaches to the disc. It is responsible for both opening your jaw, AND help stabilize the disc as your jaw moves.
As you can imagine, the most frequently affected structure of the jaw is the muscles. This may be due to the muscles being involved with every single other pain generator.
For example, if you have a disc, or joint problem it will likely cause muscular spasm, as well as joint capsule swelling and inflammation.
Furthermore, if you ‘just’ have muscle spasms or muscle pain, it may LEAD TO developing disc issues and arthritic pain down the line.
The neck connection
The neck is intimately connected to the TMJ both mechanically and neurologically. So it is not surprising that there is a high association between TMD and signs and symptoms of neck dysfunction.
This is often why neck pain, and headache can be associated with TMJ pain.
Neck? We're talking about the jaw...How are they connected?
It is well appreciated that sensory inputs from craniofacial structures such as the TMJ, teeth and dura meet with sensory inputs from the cervical region at the trigeminal nucleus. This is an area in the brain stem where nerves from all of these structures meet.
Therefore, a pain source from any of the innervated structures in the neck has the capacity to excite relay neurons in the trigeminal nucleus that also receive inputs from TMJ structures.
You could perceive pain arising from the TMJ, muscles of the jaw or teeth as a result of neck dysfunction.
So if there is a problem with one of the joints isn your neck, or with the musculature in your neck, it could cause pain to occur at the TMJ!
In fact, in addition to healthy joint alignment and function, an important indicator of chronic neck impairment is weakness of the neck flexor muscles. One might therefore expect this to be present in patients with chronic TMD. A recent study in Manual Therapy demonstrated reduced endurance of the neck muscles in patients with TMD and neck dysfunction (Armijo-Olivo 2011). It is also worth noting that weak cervical flexor muscles are highly associated with cervicogenic headache. We can therefore confidently reason an association between neck dysfunction, cervicogenic headache and chronic TMD.
Do You Have TMJ?
If you answer 'yes' to any of these questions, you may have TMJ...
- is there limitation of jaw movement?
- Is there jaw pain? This can be felt in the jaw, or around the actual joint. (The joint is right infant of the ear )Sometimes the presenters as "ear pain".
- Pain with moving your jaw
- Pain at rest
- Popping or locking of your jaw
Reasoning for a Treatment Approach
In the majority of cases, TMD is non-traumatic and there are no signs or symptoms of a sinister aetiology that requires medical attention. Based upon current understanding, the expectation is that mechanisms such as increasing proprioceptive sensibility of the TMJ will be effective in most cases.
This could be achieved with targeted joint forces, such as adjustments, and addressing muscle irritation. To improve success with TMJ, we should address any cervical dysfunction, as well as improving overall spinal alignment and stability.
By taking a global approach we aim to reduce the tendency for abnormal changes in central neurology that would predispose you to TMD.
The following quote from Jones & Rivett (2004, pp 16-17) illustrates this point:
“It is not satisfactory simply to identify structures involved, as this alone does not provide sufficient information to understand the problem and its effect on the patient, nor is it sufficient to justify the course of management chosen... of more concern is that solely tissue-based reasoning tends to promote inflexibility of management strategies.”
Approach to Treating TMJ
- We must get the pain under control. Odds are, there is likely quite a bit of inflammation within the joint, AND muscle spasms. So Reducing any inflammation, and muscle spasm must be a priority.
- If the disc is involved, we must normalize the disc function, so it is aligned with the jaw, and does not cause locking to occur.
- We need to normalize joint movement of the Jaw itself, but also the neck, as it is intimately involved with jaw movement and function.
- A holistic approach, and address any issues that may be contributing to the jaw pain. As a majority of TMJ pain is not due to trauma, there are likely lifestyle behaviours and factors that are driving the TMJ to continually be a problem.
If you would like to solve your TMJ problem, schedule an appointment today! You deserve to be able to talk and chew your food!