* Your horse reared up and fell over backward. Common scenario: He was roped, tied or being halter broke and fell over while fighting restraint. Or a medicatation was accidently given into the cartoid artery (instead of jugular vein), and he reacted by flipping over.
* Your horse reared up and struck his head on a ceiling beam, stall doorway or the ceiling of the horse trailer. Common scenario: He was fine when loaded into the trailer, but became vision impaired within three days after the accident.