Combat is one of those topics where only bits and pieces are known because they want to launch all the information with an accompanying video. We should know everything in the coming months. Until then I can answer one question for certain, one for most likely and one I have no idea!
There will not be amputations, that has been confirmed.
Whether you can slow, or even prevent, the movement of an opponent is the one I do not know about. I am not sure we have heard anything on the topic.
I do not think there is any way to bind someone or move them about without incapacitating them (knocking them out). However, if you are a Bounty Hunter, with a bounty token which allows you to bring someone to justice you can knock someone out without receiving any penalty. At that point you can drag them towards to court house! So there is certainly a place for that role.