Radial neuropathy

Overview
Radial neuropathy (or radial mononeuropathy) is a type of mononeuropathy which results from acute trauma to the radial nerve that runs the length of the arm. Saturday night palsy is a colloquial term for it.

It is known as transient paresthesia when sensation is temporarily abnormal.

Presentation
Symptoms vary depending on the severity and location of the trauma; however, common symptoms include wrist drop (the inability to flex the wrist upward when the hand is palm down); numbness of the back of the hand and wrist; and inability to voluntarily straighten the fingers.

Differential diagnosis of causes
There are many ways to acquire radial neuropathy.

The term Saturday Night Palsy refers to nerve damage that can occur if a drunk person falls asleep with the back of their arms compressed by a bar edge, bench back, or like object. Radial neuropathy is also called honeymooners palsy, since it can be acquired by sitting with an arm draped over the back of a neighboring chair (or movie-theater seat) for a long time.

Both Saturday night palsy and honeymooners palsy refer to the fact that the nerve damage is generally forewarned by arm pain to a degree that only excessive love or liquor would drive a person to keep their arm in such an uncomfortable position.

Breaking the humerus and deep puncture wounds can also cause the condition.

Prognosis
Radial neuropathy is not necessarily permanent. Peripheral nerve regeneration is an imperfect and slow process, and full restoration of ability may take months, years, or may never occur.