A neurological checkup helps a veterinarian determine whether a horse has a problem with its brain, spinal cord, or nerves (see Parts of the Nervous System in Horses). The checkup usually begins with a review of the horse’s health history and a complete physical exam. This is followed by the detailed neurological exam. In some cases, the vet might also recommend blood work, cerebrospinal fluid (CSF, the fluid that bathes the brain and spinal cord) analysis, imaging tests, or other tests to identify the cause of the horse’s symptoms.
What the Vet Checks in a Neurological Exam
During the neurological exam, the vet typically checks the horse's:
cranial nerve function
gait
neck and front legs
body, hindlegs, anus, and tail
reflexes, when possible
These checks help determine where in the nervous system the problem is located (brain, spinal cord, or peripheral nerves).
Cranial Nerve Function Exam
Horses have 12 pairs of cranial nerves, which control the horse's sense of smell, vision, eye movements, facial movements, hearing, balance, chewing, swallowing, vocalization, and tongue movement. Testing all of these functions can help determine where in the brain any damage might be located, on the basis of alertness, head position, coordination, and facial reflexes.
Gait Evaluation
A horse's "gait" is how it walks and moves. The vet watches the horse walk, trot, turn, step sideways, and back up. Signs of neurological disease can include circling, stumbling, falling, weakness, paralysis, rolling unexpectedly, and poor coordination. Sometimes the horse is also asked to walk uphill, downhill, or over a curb to reveal subtle problems.
Neck, Legs, Trunk, and Rear End Exam
The vet checks the horse's entire body for pain, poor muscle tone, numbness, posture changes, spinal abnormalities, oversensitivity, and muscle loss. Muscle shrinking in one area may suggest nerve damage to that muscle.
Additional Tests in the Neurological Checkup
Other tests may include:
blood tests, which can detect toxins, some infections, and problems with the body's internal chemistry
CSF tests, which can reveal inflammation, infection, bleeding, tumors, or spinal cord pressure
imaging tests (x-rays, CAT scans, or MRIs), which can identify fractures, bone changes, internal bleeding, abscesses, inflammation, and some cancers
an electroencephalogram (EEG), which records electrical activity in the brain and can help detect seizures
a hearing test called a brainstem auditory evoked response (or BAER) test, which helps identify hearing loss or brainstem problems
For More Information
Also see professional content regarding the neurological evaluation.
