Encyclopedia of Health and Medicine

D–G
dislocations Separations of the structures within
a JOINT, typically as a result of traumatic injury.
The digits (fingers and toes), shoulders, and hips
are particularly vulnerable to dislocation. Traumatic
dislocation is very painful. Generally a doctor
should reduce the dislocation (restore the
bones to their correct positions) and evaluate the
injury for any damage that would require additional
treatment; however, people tend to “pop”
dislocations back into place themselves. Such selftreatment
can cause further trauma, depending on
the circumstances. Splinting the joint and applying
ice to the area can reduce swelling and PAIN
until the doctor can realign the structures. Sometimes
a dislocation reflects an abnormality of the
joint that requires a doctor’s assessment and treatment
to prevent subsequent dislocations.
See also FRACTURE; RICE; SPRAINS AND STRAINS.
dwarfism
See SKELETAL DYSPLASIA.
dystonia Extended contractions of the muscles
that hold the body in unnatural postures. Dystonia
may occur as a primary disorder of movement,
typically a hereditary disorder, or as an undesired
SIDE EFFECT of certain medications to treat PARKIN-
SON’S DISEASE, PSYCHOSIS, SCHIZOPHRENIA, and SEIZURE
DISORDERS that affect DOPAMINE binding in the
BRAIN. Dopamine is a key NEUROTRANSMITTER for
movement as well as for mood. Sometimes,
though unfortunately not always, stopping the
medication ends DRUG-related dystonia. Inherited
forms of primary dystonia may be spastic (involve
rigid, distorted postures) or repetitious, often
rhythmic, involuntary movements such as grimaces,
twitches, and jerking.
There are no treatments for primary dystonia
that are certain to stop the MUSCLE contractions.
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Some people experience relief with high doses of
anticholinergic drugs that affect acetylcholine, a
neurotransmitter important to fine motor movements.
When the dystonia occurs in a localized or
regional part of the body, BOTULINUM THERAPY
(injections of weakened botulinum toxin) sometimes
can paralyze the muscles enough to significantly
reduce or eliminate the dystonia. The
effects of botulinum therapy are temporary, however,
with repeat treatments required about every
six months.
See also BLEPHAROSPASM; SPASM; TIC; TORTICOLLIS.
epicondylitis INFLAMMATION of the TENDON at the
elbow end of the humerus (long BONE of the upper
arm). Epicondylitis may be lateral or medial. Lateral
epicondylitis, commonly called tennis elbow,
affects the outer side of the elbow (little finger
side). Bending the wrist back or applying pressure
to the bony projection (the humeral epicondyle)
on the outside of the elbow causes PAIN at the
elbow. Painting and plastering are common occupational
causes of lateral epicondylitis. Medial epicondylitis,
commonly called baseball elbow or
golfer’s elbow, affects the inner side of the elbow
(thumb side). Bending the wrist toward the palm
of the hand or squeezing a ball held in the palm of
the hand causes pain at the base of the elbow.
The doctor makes the diagnosis on the basis of
symptoms and personal history of overuse or a
blow to the elbow. Diagnostic procedures are usually
not necessary. Treatment combines NON-
STEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS) or
injections of CORTICOSTEROID MEDICATIONS, which
reduce inflammation and pain, with alternating
heat and cold to the area. A brace or band worn
over the humeral epicondyle provides relief for
some people. Epicondylitis generally goes away in