Okay.
Did anyone get the number of that 777? 
I question that…
That is a strike to the side of the neck, not the inside of the arm. Here is a description of braxial plexus injuries. To wit:
The strike, AFAIK, is to the side of the neck, right where Frankenstein’s lug-nuts are. (A description I believe I read here somewhere).
But yeah, a nerve strike. Some are more effective than others, and all are subjective. Hitting a no-neck defensive linebacker in that same spot might just piss the guy off, not drop him like a sack.
-Tcat
Ooh! Found a pic!
Guess I was wrong, but c’mon, brachial means arm, dammit!
http://www.cincinnatichildrens.org/health/info/neurology/diagnose/brachial-plexus.htm
The origin of the nerve is from the C5 vertebrae.
-Tcat