Check out Shea's most recent publishing, The Importance of The TMJ and CranioSacral Therapy
TMJ dysfunction is probably one of the most unrecognized issues that many horses suffer from today. TMJ pain, which mostly involves soft tissue and ligament strain, can lead to posture imbalances affecting other joints in the body. Imbalance and pain in this joint can turn into TMJ dysfunction (TMD), which is remodeling of the joint and distortion of other bones in the cranium. This is a serious concern affecting our horses today. TMJ issues can result in ulcers, colic, lameness, and performance issues, just to name a few.
The Temporomandibular Joint (TMJ) is where the mandible articulates with the temporal bone, and might just be the most critical and most complicated joint in a horse. This joint is the fastest changing joint, and the closest joint to the brain and brain stem. The TMJ is highly innervated, and is surrounded by structures that dictate the horse's balance and sensory perceptions. The quality of feedback in the nervous system is affected by the health of this joint. The neurology is too involved to detail in this page, however there is an intricate web of information weaving throughout the TMJ, throat latch, and poll that directly affect biomechanics and neurology of the whole horse.
The TMJ has two primary functions, mastication (mandible) and balance (temporal bone). Any change in bite or movement of the jaw, will cause change in the joint. The muscles and ligaments associated with mastication (chewing), also attach to other important bones in the cranium. So when a horse is not chewing correctly, this will cause muscle tightness or weakness that will pull on the bones in the cranium--most importantly, the bone that the brain rests in, called the sphenoid bone. Therefore, TMJ dysfunction can affect the central nervous system, causing a slew of issues that might be considered unrelated. Another importance of TMJ, is its relationship to c1 and c2, also known as “the poll". The axis of rotation for the mandible (jaw) is at c1 and c2. So TMJ affects the mobility of the neck, and the neck affects the mobility of the TMJ. How many chiropractors adjust the pole because the poll is out? Why does our horse’s poll joint constantly need adjusting from a chiropractor?
There is also a spiritual and emotional aspect of the TMJ. The jaw is the most emotionally invested bone. A lot of emotions are reflected in mandible movement, such as anger, stress, peace, calmness, etc. When the jaw is restricted in movement, it has a physical effect and an emotional effect.
So, in short, the TMJ can be linked to psychological and physical issues, internal organ imbalances, and body compensations, due to the fact that the nervous system is associated with this delicate joint.
The TMJ is also one structure that is part of a system (stomatognathic system) that works in harmony to perform different functional tasks. These structures are located from the neck up, and attach to the cervical region of the spinal cord. This is why we often see a reciprocal pattern in the pelvis with TMJ issues. Where the head goes, the body goes. Therefore, restrictions in TMJ restrict head and neck mobility, which restrics rib cage movement and pelvis mobility. There are also acupuncture meridians that flow around the TMJ that go down the entire body to the pelvis. This also explains why pelvis movement is affected by TMJ issues.
We as horse owners trust our vets and dentists to do the right thing when it comes to floating teeth, however all floats are not created equal. Too many horses today are being overly power floated with their heads propped up on stands, while the only focus is on taking down sharp points and side to side occlusion. This results in horses losing their grinding surface, and flattened table angles. Also incisors are not being balanced which puts more strain on the TMJ, causing pain and discomfort when bits and nosebands are used. Finding a proper dentist who balances the mouth to the TMJ is crucial in health of this joint. But proper dentistry alone is not the only answer. Once the mouth is balanced, relieving muscle tension and restoring cranial rhythm will be just as important.
Other causes of TMJ issues are pulling back while tied, head traumas, falls, tight or restrictive head gear, ill-fitting tack, poor riding and horsemanship.
If you would like a consultation to understand more about the health of your horse's TMJ, contact Shea for an appointment. The PHOTO page has some examples to look for in TMJ health.