Function to have broken bones. For example whenever I get chased to the big parking lot, I can just jump from the top floor and not be harmed (A few seconds of ragdoll is not that realistic). If you could have your leg/legs broken from falling somewhere high, it would reduce your mobility significantly, occasionally make you trip and take a good portion of your damage. This would also give medical team more stuff to do as they would need to use splints and other medical items. Also bandages would be good when hit in center mass, and tourniquets for major veins e.g legs and arms. This would make combat much more thrilling and even if you could manage to kill your enemy, without medical supplies you very well could die aswell.