Like shaftnem said...something happened to the pedicel so it is bent over and facing the wrong direction. The first pic is the best to see how the one pedicel is facing up and the other pedicel is all funky looking and facing down. Due to the pedicel facing that direction the antler would have always growm that way.
The first buck my dad ever shot was similar to that. It had a normal forked antler on one side, and the other side grew straight down next to its face.