Originally Posted by
Cherchez
both of these species are not thread worthy son.
[h1]Wrist drop[/h1][h3]From Wikipedia, the free encyclopedia[/h3]
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[th=""]Wrist drop[/th]
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ICD
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ICD
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Wrist drop, also known as
radial nerve palsy,or
Saturday night palsy, is a condition where a person can not extend their
wrist and it hangs
flaccidly. To demonstrate wrist drop, hold your arm out in front of you with your forearm parallel to the floor. With theback of your hand facing the ceiling (i.e.
pronated), let your handhang limply so that your fingers point downward. A person with wrist drop would be unable to move from this position to one in which the fingers are pointingup towards the ceiling.
[h2][
edit] Anatomy of the forearm[/h2]
In anatomical parlance, the
forearm is the part of the body which extends from the elbowto the wrist and is not to be confused with the arm which extends from the shoulder to the elbow. The extensor muscles in the forearm are
extensor carpi ulnaris,
extensor digiti minimi,
extensor digitorum,
extensor indicis,
extensor pollicis longus,
extensor pollicis brevis,
extensor carpi radialis brevis,
extensor carpi radialislongus. These extensor muscles are supplied by the
radial nerve. Other musclesin the forearm also innervated by the radial nerve are
supinator and
abductor pollicis longus. Note thatall these muscles are situated in the posterior half of the forearm (posterior when in the
anatomical position). Also,
brachioradialis,
anconeus,
triceps brachii, and
extensor carpi radialis longus areall innervated by muscular branches of the radial nerve in the arm.
[h2][
edit] Causes[/h2]
Wrist extension is achieved by
muscles in the
forearm contracting, pulling on
tendons that attach distal to (beyond) the wrist. If the tendons, the muscles, or the
nerves supplying these muscles, are not working as they should be, wrist drop may occur. The following situations may result in wrist drop:
Stab wounds to the chest at or below the clavicle may result in wrist drop. The radial nerve is the terminal branch of the posterior cord of the
brachial plexus. A stab wound may damage the posterior cord and result inneurological deficits including an inability to abduct the shoulder beyond 15 degrees, an inability to extend the forearm, reduced ability to supinate thehand, reduced ability to abduct the thumb and sensory loss to the posterior surface of the arm and hand.
The radial nerve can be damaged if the
humerus (the bone of the arm) is broken, becauseit runs through the radial groove on the lateral border of this bone.
Wrist drop is also associated with
lead poisoning because of the effect of
lead on the radial nerve.[sup]
[1][/sup]
Persistent injury to the nerve is also a common cause through either repetitive motion or by applying pressure externally along the route of the radialnerve as in the prolonged use of crutches or extended leaning on the elbows.
[h2][
edit] Diagnosis[/h2]
The
workup for wrist drop frequently includes
nerve conduction velocity studies to isolateand confirm the radial nerve as the source of the problem.
Plain films can help identify bone spurs and fractures that may have injured the nerve. Sometimes
MRI imaging is required to differentiate subtle causes.
[h2][
edit] Treatment[/h2]
Initial management includes
splinting of the wrist for supportalong with
occupational or
physical therapy. In some cases
surgical removal of bone spurs or other anatomicaldefects that may be impinging on the nerve might be warranted.
[h2] [/h2]