Head injuries are not uncommon in horses. Head trauma is a difficult injury to treat because of the direct effects of the injury on brain tissue and the secondary complications that can occur. Head trauma affects all ages of horses, although young horses seem to be more likely to be affected. Head trauma can lead to damage of vital brain structures with bleeding or infected tissues around the brain. Also, bone fractures in the head area can occur, especially in horses that flip over backwards or run into an immovable object. Common signs noted with head trauma include an altered level of consciousness, abnormal behavior, and cranial nerve deficits. Cranial nerve deficit symptoms include a head tilt, inability to open the eyelids completely or blink, and an inability to swallow and hold the tongue in the mouth.

Concussions can occur that result in a brief loss of consciousness, while a contusion indicates a distinct area of swollen brain tissue and damage to the blood supply. Concussions do not result in permanent brain damage and usually have a favorable prognosis. However, bleeding into the closed brain cavity can result in serious injury, and any brain injury may initially seem mild but can become severe due to bleeding or infection. For this reason, any horse with suspected brain trauma should be examined by a veterinarian immediately and monitored carefully for at least 24 hours after the injury. Horses with traumatic brain injury will commonly need intravenous fluid therapy to correct low blood pressure, as the brain is very sensitive. Horses may also be aided by treatment with intravenous dimethyl sulfoxide (DMSO), cortisone, and other anti-inflammatories as well as decompressive surgery, although this procedure is questionable.