If she tore her CCL it needs to be repaired. Yes, she might start walking on it again, but she will end up with horrible arthritis in the joint if it is not repaired.
Here is a link to an article written by the board certified surgeon I use:
Yorkie Haven Rescue - Cranial Cruciate Ligament Tear Info
My suggestion is to find a boarded surgeon in your area who does surgery on knees and get his/her opinion on this. And, no, you don't wrap them.