Of all the injuries your horse may sustain over the course of his life, serious head trauma is one of the least likely. Yet more than a few of us have witnessed a fast-moving horse unexpectedly collide head-on with a tree or other obstacle. And there are those who wince at the remembrance of a rearing horse falling over backward and striking his head on an unforgiving stable aisle. Perhaps the susceptibility of our own brains to concussion heightens our concern for the well-being of any horse who accidentally whacks his head--or worse.
In most instances, the design of the equine skull provides ample protection for the brain so that even extensive damage to the bony capsule leaves the gray matter unscathed. This knowledge may be small consolation, however, when your horse staggers in from the pasture bearing evidence of a herdmate's forceful kick to the face.
An understanding of the anatomy of the equine head as well as an awareness of the signs indicative of superficial to serious trauma will help guide you in your initial handling of a horse with a head injury while also preparing you to talk with your veterinarian about the specific diagnosis, treatment options and prognosis for recovery.
A Basis for Assessment
The equine cranium is a complex series of 16 broad, thin, interlocking bones connected at immobile joints called sutures. The majority of a horse's skull--about three-quarters--encloses and protects the long nasal passages as well as the teeth and mouth; smaller areas encase the eyes and the structures of the inner ear. The brain is contained in a compact space within a series of six bones, called the calvarium or brain box. An almost circular opening in the base of the box accommodates the spinal cord.
In addition to giving the face its substance and structure, the long expanse of the equine skull serves the same protective purpose as the "crumple zone" on a car, absorbing the impact of a collision before the force can reach the brain and do it harm. The design works so well that many veterinarians never will encounter a horse with a true brain injury in the course of their careers. As a horse owner, you're even less likely to see one.
What you may encounter is a routine head injury of some sort, and the sight can be alarming. With its extensive vascular network, the head bleeds easily and copiously so that even a relatively minor wound can look quite serious. But, given proper attention, even badly marred facial flesh and bone will mend over time, in part because of the abundant local circulation.
Unless an injury directly affects the brain, the prognosis for a full recovery typically is very good. Determining whether a blow to the head has affected the brain can be tricky, however, because the look of a wound alone doesn't supply sufficient evidence of its severity. When evaluating any trauma to the head, it's also essential to consider how the horse is behaving.
If you see your horse hit his head or suspect he has, approach and examine him carefully, asking yourself the following questions. The answers may put some of your fears to rest while helping to organize your thoughts for the call to the veterinarian.
1. Can he rise? Don't force a horse with a head injury to get up. Simply watch to see if he attempts it. A horse who rises quickly and stands normally and steadily probably is not suffering from neurological trauma. A horse who is dazed may lie still until he gets his bearings, then he'll slowly but successfully rise. In contrast, a horse with a serious head injury may panic as he attempts to stand and fails. He also may move his head and legs aimlessly or convulsively.
2. Can he see? A horse who follows you with his eyes or reacts when you wave a hand near his face most likely can see, which is an important indication of brain function.
3. Can he walk? Don't force an injured horse to walk. Take stock of his general condition while he's standing still then encourage him to follow you. It's good news if he's able to move in a coordinated fashion. If, however, he refuses to move, check for a mechanical injury, such as fractured withers, that may make walking painful. Suspect neurological trauma if he tries to move and cannot seem to position his legs properly or he collapses.