This is an answer I gave on Reddit.com to the question of treating muscle spasm in TMD disorders associated with a close-lock TMJ. A link to discussion will be at bottom of post

“What would you recommend doing about the muscle spasms?” is an excellent question. The first step is to make a specific diagnosis. You question is perfectly meaningless without understanding the type of muscle spasm we are talking about.

Acute Muscle Spasm is usually related to specific trauma and treatment is symptom specific. This does need to be differentially diagnosed from myoclonic muscle problems (both positive and negative) which could be related to underlying disorder.

Acute muscle spasm and muscle splinting can be closely related when an acute injury leads to muscle splinting or contacture of muscles to protect an area of injury. This can be a muscle tear, broken bone, damaged joint or tendon or tendon attachment problem. A blood clot can also result in acute muscle spasm but is rear in TMD.

Acute muscle spasm will usually self correct and is probably what happened to you in the episode you descibed as a close-lock though it is possible you had acute spasm and a partial dislocation of the disk.

Muscle splinting is an important body function that protects against additional injury and allows some function.

If the injury is a muscle tear or if the spasm is strong enough to cause a tear in the muscle you have a completely different problem. You will still have splinting and severe muscle inflamation and ice will usually be first line of approach. It is also possible to tear a tendon or have enthesis of tendon attachment. These all appear very similar to acute muscle spasm but are very different.

Muscle Splinting can lead to Myofascial Pain and Dysfunction (MPD) with trigger points, taut bands and referred pain. This is the most common type of pain anywhere in the body and is often misdiagnosed to the fact that the pain and where it is coming from are usually not correctly identified when doctors are not familiar with these problems. In the TMD field this often leads to Root Canal Treatment, Extractions and diagnosis of non-existent sinus or ear infections

MPD diagnosis is crucial. When confronted with this type of “muscle spasm” Travell Spray and Stretch techniques can often give instantaneous relief. Hot and Cold and Stretching can all be useful. Teaching patients to use Spray and

Stretch with vapocoolants at home is ideal and should be taught to patient. MPD is caused by repetive strain injuries and correction of these problems is important. This may be related to postural condition, anxiety and stress and muscle misuse. Not correcting underlying structural issues is unwise for many patients, it is ethically required to explain postural considerations including bite to patients.

Treatment with ULF-TENS is an excellent modality. The Myomonitor has been used to relax muscles in Neuromuscular Dentistry for over 50 years. It works as a muscle stim peripherally causing muscles to contract and relax every 1.5 seconds. This time is based on time it takes nerve and muscle membranes to return to normal after firing. This effectively eliminates fatigue and and causes repetitive contraction and relaxation of muscles increasing blood flow with nutrients from blood and taking away waste products.

NMD usues this on muscles innervated by the Trigeminal Nerve and the Facial Nerve (cranial nerves 5 and 7 respectively). In TMD patients this relaxes all muscles that are trigeminally innervated. This includes the masseters, the medial pterygoids, the temporalis, the superior and inferion lateral pterygoids, the sphenomandibularis, the Tensor Veli Palatini that opens and closes eustacian tubes and the Tensor Veli Tympani that cotrols tension and eardrum and the anterior belly of the digastric. It also works on muscles innervated by facial nerves when used in standard position over coronoid notch.

The myomonitor can also be used on muscles anywhere in the body directly or indirectly such as on accessory nerve (cranial nerve XI) to work on upper neck, back and shoulder muscles. The BioTens is another ULF-TENS that is used by some NMD dentists. There are many reasons why the Myomonitor is special in dealing with bites and high tech adjustments but the BioTens is excellent at relaxing muscles and I often use it on Cranial nerve XI.

Nutrition is important in dealing with muscle issues and muscles require both calcium and magnesium to contract and to relax. Some medications can cause severe muscle pain and issues.

Trigger point injections, dry needling, prolotherapy, prolozone therapy are all used to treat muscle spasm and taut bands. Spray and Stretch should be utilized with injections .

Posture stability is key. This video https://www.youtube.com/watch?v=kdWhfeOcFAQ is a patient with TMD/ Headache/Migraine that is secondary to postural instability of hips. Treatment will fail if initial problem is ignored. This patient had a similar experience years previously.

We swallow 2000 times a day when our teeth touch momentarily when there is underlying postural instability we are more likely to have repetitive strain injuries. Clenching, grinding and misuse of muscles exacerbates these problems. Preventing issues is more effective than treating them after the fact. It is far easier to change the oil than change the engine in your car. It s better to prevent severe damage to TM Joints that wait till there is a disaster.

Locked Jaw – Is this permanent damage to my jaw? from TMJ