By back slap do you mean grazing the top of its back?
Yes....most likely high on the shoulder/lower neck area. If you look at a deer's anatomy....the spinal column has a dip in it right in that area that leaves a chunk of meat above the spine that can pretty much be blown off but the deer still get up and walk away from. It just shocks their spinal chord and causes them to have temporary paralysis or maybe even partial paralysis. The shock eventually wears off and they get their legs up in under themselves again. A lot of folks aim for dead center of the shoulder and when they miss high, they hit this area. Any deer that hits the ground, lays there for a while, and then gets up and runs off is not likely to be recovered. Some will but just going on percentages that is a very, very low percentage find. Very often the deer just shows back up on camera.
