The only expeience I have with spine hits was with a dead 6-point I found laying out in the middle of an open field. I walked over to check it out, noticed a small wound high on it's back, and dug out the front 2" of an aluminum shaft along with a 100 grain Thunderhead. Someone apparently hit it from a treestand, but the arrow lodged in the vertebrae before ever reaching the spinal cord. I suppose infection took over eventually.