Last year my friend called me he found a deer that tried to jump his fence and somehow got her rear leg caught in the top wires and was laying with her front body on the ground with her leg up at about a 55 degree angle.
I helped him get her out and she didn't run away, wouldn't move so we put her in the tractor bucket and took her to his dog kennel hoping she would recover.
Two days later she still wasn't moving, I called another friend he told me if she was in the fence for a good while that the leg didn't get enough blood flow and it's basically dead.
Now deer seem to be pretty resilient but they are fragile in other ways. Took out in the pasture and put her down.