Ed
That is a hammer for sure!
There is a lot of meat above the spine in that part of the back, I'm confident that the shot was just a loin hit. See the anatomy guides in Rob's first post:
http://www.huntingnet.com/forum/bowh...fter-shot.html
The biologists say that a buck's biology is especially geared to survive puncture wounds from fights this time of year, so an arrow wound in the loin is not going to be a challenge. I have similar pics of a doe on a trail cam, a few weeks after a friend hit her in the loin. She fed normally and you could see that the wound was healing.
Good luck with that hammer!
-fsh