temporomandibular disorders A group of con-
ditions in which there is INFLAMMATIONand often
degeneration of the temporomandibular JOINT, the
large joint that connects the lower jaw (mandible)
to the temporal BONEof the cranium. There are
numerous possible causes for temporomandibular
disorders, ranging from a CONGENITAL ANOMALYof
structure (such as uneven bite) to OSTEOARTHRITIS
and grinding the TEETH(bruxism).
Symptoms and Diagnostic Path
The symptoms of temporomandibular disorders
include
- inability to fully open the MOUTH
- locking of the jaw when open
- clicking sounds or sensations when chewing
- PAINin the temporomandibular joint
- chronic HEADACHE
The diagnostic path begins with a comprehen-
sive examination of the head and mouth. Some-
times the doctor determines the cause is primarily
dental, such as uneven bite, and refers the person
to a dentist for evaluation and treatment. Deterio-
ration and inflammation of the joint are medical
problems the doctor can attempt to treat. X-RAY
can show whether there is a misalignment of the
joint structures or deterioration of the bones.
There is usually no need for additional diagnostic
procedures unless the doctor feels the need to rule
out other causes for the symptoms.
Treatment Options and Outlook
Treatment for temporomandibular disorders may
include medications such as NONSTEROIDAL ANTI-
INFLAMMATORY DRUGS(NSAIDS) to relieve inflamma-
tion and pain, heat or cold to the joint, dental
splints or other devices to realign the bite, and
dental repairs, if necessary. Temporomandibular
disorders tend to be chronic. Many people put up
with the discomfort for a considerable time before
seeking medical care, by which time joint deterio-
ration or other problems may be serious. Treat-
ment may take time to be effective. In rare
circumstances, usually when injury or congenital
anomaly causes a structural problem with the
joint, surgery may be necessary.
Risk Factors and Preventive Measures
Stress is often a significant factor in the circum-
stances that contribute to temporomandibular dis-
orders, particularly with bruxism and clenching of
the jaw, which causes irritation of the muscles and
other tissues in the joint area. Many people find
their symptoms improve with a combination of
direct treatment (such as NSAIDs and heat) and
indirect approaches such as MEDITATIONor other
stress-reduction techniques. These measures can
reduce MUSCLEtension.
See also CHRONIC PAIN.
tendon A tough, fibrous band of connective tis-
sue that joins MUSCLEto BONE. A tendon originates
in the muscle. Like muscle, tendons have a rich
BLOODand NERVEsupply. At its other end the ten-
don inserts into the bone. Mineralization at the
insertion point creates a contiguous flow of tissue
from muscle to bone. The largest tendon in the
body is the ACHILLES TENDON, which joins the mus-
cles of the calf to the bone of the heel. The most
common health conditions involving tendons are
TENDONITIS(INFLAMMATIONof a tendon) and tendon
rupture (a tear in the tendon).
See also BURSA; LIGAMENT; PATELLOFEMORAL SYN-
DROME; ROTATOR CUFF IMPINGEMENT SYNDROME.
tendonitis INFLAMMATIONof a TENDON. Tendonitis
most often occurs as an overuse injury. Overuse
causes the fibers of the tendon to stretch and
tear, leaving microscopic injuries throughout
the tendon. Occasionally calcium deposits develop
in a tendon. The injury activates the IMMUNE
RESPONSE, which in turn initiates the inflammatory
response.
The main symptoms of tendonitis are PAINat
the tendon’s insertion point on the BONE and
swelling over the site. Tendonitis most commonly
occurs at the wrist, elbow, shoulder, knee,
ACHILLES TENDON, and heel. Within the first 24
hours, RICE(rest, ice, elevation, and compression)
is the most effective therapeutic approach. NON-
STEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS) help
relieve PAIN and inflammation. Most tendonitis
improves within 72 hours and completely heals in
two to three weeks with appropriate treatment.
See also ACHILLES TENDON INJURY; ADHESIVE CAP-
SULITIS; EPICONDYLITIS; PATELLOFEMORAL SYNDROME;
tendonitis 359