Wristdrop is a type of paralysis in which the wrist
and/or fingers cannot be extended or lifted. Paralysis
is loss of movement and/or sensation. Wristdrop is
caused by damage to the radial nerve. The radial
nerve is a long nerve that normally supplies impulses
to the skin of the arm and forearm, as well as muscles
that help extend the arm and forearm. If the radial
nerve is compressed, it cannot transmit sensory-motor
impulses. The damage to the radial nerve is usually
somewhere in the armpit or upper arm. Putting the
wrist in a splint to keep it straight may help restore
functioning of the radial nerve.

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Wristdrop is also known as Saturday night palsy because it often happens to intoxicated
people who fall asleep in a chair after partying. Normally, people move around in their
sleep which prevents constant compression of the radial nerve. People who are drunk do
not move as much in their sleep and the radial nerve can be constantly compressed, such
as by hanging the arm over a chair.

Wristdrop comes from the Proto-Germanic word “wrig” meaning “to turn” and from the Old
English word “dropian” meaning “to fall in drops.” Put the words together and you get to
turn and fall in drops.”
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