If rearing with a rider is not clearly linked to fear, disobedience or aggression, it may be linked to pain. An equine veterinarian can examine the horse's mouth and teeth, back, and feet for possible causes. Pain may also be linked to poorly fitted or improperly used tack. A rider or saddle-fitting specialist can determine if pain is linked to a poorly fitted saddle, or a broken saddle tree. The fit and severity of the bit can also lead to rearing.