I would never have thought this was a real thing until I found references for it detailing a number of cases.
Saturday Night Palsy, also known as Radial Neuropathy, is caused by getting rip roaringly drunk and falling asleep in an unusual position such that the radial nerve is compressed. Most commonly this happens when the patient falls asleep with one arm over the back of a chair putting pressure on the radial nerve, which runs alongside the inside of the arm, by compressing the brachial plexus.
Related palsies include Honeymoon Palsy, which is a little rarer now than it once was, is also commonly alcohol related but comes down to new couples that are not used to sleeping next to each other wind sleeping on each others arms resulting in compression of the radial or median nerves which in turn results in paralysis.
Another common palsy is Handcuff Palsy caused by the application of handcuffs too tightly. This compresses the distal branches the distal nerve and you get more paralysis.
Unlike the central nervous system, nerves in the periphery can and do regrow but they will take their time. It may take weeks until strength and mobility return and even then it requires close monitoring and support to regain full control.
This story is all too familiar to arguably the most famous sufferer of Saturday Night Palsy, Dave Mustaine. Mustaine was dumped by Metallica because he was too Rock-n-Roll and then started a new band called Megadeth. Megadeth was started from one reason "After getting fired from Metallica, all I remember is that I wanted blood. Theirs. I wanted to be faster and heavier than them". This was a properly hardcore guy. What are the chances he was going to get blind in a chair? Really was just a matter of when. In 2002 Mustaine was hospitalised to remove a kidney stone, received pain meds, suffered a relapse, admitted to a treatment centre, passed out in a chair with his arm hanging over the back causing his palsy.
Depending on your feelings about he music or Megadeth the palsy caused something tragic/amazing to happen, with Mustaine unable to hold a guitar he disbanded Megadeth while he underwent physical therapy. The band reformed eventually when he could play again in 2004.
I have never fallen asleep in a chair, am quite familiar in safe couples sleeping techniques and have never been handcuffed so I would say I’m probably at low risk of these transient radial neuropathies but you can never be too careful. So in this party season always remember to sleep safe!
ReferencesMarchini C, Zambito Marsala S, Cavagna E, & Ferracci F (2007). Saturday night brachial plexus palsy. Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology, 28 (5), 279-81 PMID: 17972044
Sathornsumetee S, & Morgenlander JC (2006). Friday night palsy: an unusual case of brachial plexus neuropathy. Clinical neurology and neurosurgery, 108 (2), 191-2 PMID: 16412841