It appears to have broken the skull under that pedicle, since the pedicle/antler is facing forward. That broken skull will grow back together and he will shed that side. It will more than likely grow an abnormal side on that side from now on. I would bet, if you see him running that side will be moving around. The skin is all that is holding it in place. Seen this a few times over the years and almost all of the bucks end up with a NT side.