Are you serious? We are not talking about a sore muscle or a little owie here. The sort of deep damage for which people receive oxycodone is a different order of magnitude. It's clear you've never experienced that level of agony. I hope you never do.
He told me to sit down in a chair and lean forward. He sprayed my back with a very cold spray and then rub it right where the nerve would be. I got up like I had never had a back problem in my life. Sports trainers in high school, college, and Pro levels use the technique when a players nerve pinches or a muscle won't release. That's why you see them come back in after a few minutes.
That said this is not the same as nerve damage which can vary to very great extremes from person to person. Also persons tolerance levels are different and it's rather stupid of some who are saying By Golly I got up and got moving so By Golly you can too nonsense.
Where the damage is, the internals of the CNS and how the brain itself translates it can mean everything. So can an eighth of a inch in location.
A lot of people don't realize this but even quadriplegics can often feel pain throughout their body although they may or may not be able to pin point the exact location of exactly where. A minor issue such a being touched somewhere can cause them to scream in pain yet a surgery they may not request much post op medication. Each person is different that's the way GOD made us.