Protection. Preventing further injury.

Seems… pointless? Obviously protect all of you from further injury insomuch as you can.

It seems like someone just wanted to invent another acronym.

It's not meant to be general protection, like wearing shin guards next time so you don't get hurt at all.

Instead, they mean that you should protect the injury so that it's not exacerbated: brace it or put it in a sling, have the patient use crutches, etc.