4.01 Temporomandibular Joint Pain-Dysfunction Syndrome
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Presentation
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Patients usually complain of poorly-localized 
facial pain or headache that does not appear to 
conform to a strict anatomical distribution. 
The pain is generally dull and unilateral, 
centered in the temple, above and behind the 
eye, in and around the ear. The pain may be 
associated with instability of the 
temporomandibular joint (TMJ), crepitus, or 
clicking with movement of the jaw. It is often 
described as an earache. Other less obvious 
symptoms include radiation of pain down the 
carotic sheath, tinnitus, dizziness, decreased 
hearing, itching, sinus symptoms, a foreign 
body sensation in the external ear canal, 
trigenimal, occipital and glossopharyngeal 
neuralgias. Patients may have been previously 
diagnosed as suffering from migraine headaches, 
sinusitis or recurrent external otitis. 
Predisposing factors include malocclusion, 
recent extensive dental work, or a habit of 
grinding the teeth (bruxism), all of which put 
unusual stress upon the TM joint. Clinical 
signs include tenderness of the chewing 
muscles, the ear canal or the joint itself, 
restricted opening of the jaw or lateral 
deviation on opening, and a normal neurological 
examination.

What to do:
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- Examine the head thoroughly for other causes 
   of the pain, including visual acuity, 
   cranial nerves, and palpation of the scalp 
   muscles and the temporal arteries. Pain and 
   popping on moving the TMJ is a useful but 
   not infallible sign. Look for signs of 
   bruxism, such as ground-down teeth. If there 
   is a headache, perform a complete neurologic 
   examination, including fundoscopy. If the 
   temporal artery is tender, swollen or 
   inflamed, send blood for an erythrocyte 
   sedimentation rate.
- If pain is severe, you may try injecting the 
   TMJ, just anterior to the tragus, with l ml 
   of plain lidocaine or bupivicaine, along 
   with 10mg of DepoMedrol. If this helps, you 
   may have made the diagnosis, and possibly 
   provided long-term relief.
- Explain to the patient the pathophysiology of 
   the syndrome: how many different symptoms 
   may be produced by inflammation at one 
   joint, how TMJ pain is not necessarily 
   related to arthritis at other joints, and 
   how common it is (some estimates are as high 
   as 20% of the population).
- Prescribe anti-inflammatory analgesics (e.g., 
   aspirin, ibuprofen, naproxen), a soft diet, 
   heat, and muscle relaxants (e.g., diazepam) 
   if necessary for muscle spasm.
- Refer the patient for followup to a dentist 
   or otolaryngologist who has some interest in 
   and experience with TMJ problems. Long-term 
   treatments include orthodontic correction, 
   physical therapy and sometimes psychotherapy 
   and antidepressants.

What not to do:
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- Do not rule out TMJ arthritis simply because 
   the joint is not tender on your examination. 
   This syndrome typically fluctuates, and the 
   diagnosis often is made on history alone.
- Do not omit the TMJ in your workup of any 
   headache.
- Do not give narcotics unless there is going 
   to be early follow up.

Discussion
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The relative etiologic roles of inadequate 
dentition, unsatisfactory occlusion, dysfunct- 
ion of the masticatory muscles and emotional 
disorders remain controversial. To stress the 
role played by muscles, it has been suggested 
that the term "myofascial pain-dysfunction 
(MPD) syndrome is more accurate than "TMJ 
arthritis." There is also much debate as to the 
indications for and the efficacy of treatment 
modalities aimed at the presumed etiologies. At 
the least, irreversible treatments such as 
surgery should be replaced by more conservative 
therapy. The use of bite blocks for bruxism was 
based on outdated information and may only 
serve to alter normal dental occlusion with 
deleterious effects.

Perhaps everyone suffers pain in the TMJ 
occasionally, and only a few require treatment 
or modification of lifestyle to reduce 
symptoms. In the ED the diagnosis of TMJ pain 
is often suspected, but seldom made definit- 
ively. It can be gratifying, however, to see 
patients with a myriad of seemingly unrelated 
symptoms respond dramatically after only 
conservative measures and advice.

References
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- Guralnick W, Kaban LB, Merrill RG: 
   Temporomandibular joint afflictions. *N Eng 
   J Med* 1978:299:123-128.
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