It's been my experience that it can't be treated. I don't think there's ANYTHING that can be done. You have to wait till the two ends of the nerve, before they disappeared into whatever's trapping them, usually bone, to join up again.
A hot water bottle may ease the pain a little but the only way to treat it from my experience is to wait for it to go. I have trapped a nerve in my neck before just by looking up, took about a day to go away.