A pre-purchase exam is a complete physical and lameness evaluation performed by a veterinarian for a potential buyer of a horse. The purpose is to determine what, if any, health or lameness problems the horse has today and what problems it may develop in the future. People often say that a horse either passed or failed a pre-purchase examination, but this is not an accurate statement. The pre-purchase exam is not a pass/fail situation. With rare exceptions, I have found some problem worth discussing with the potential buyer in every pre-purchase exam I have performed.
Rather than looking at this as a pass/fail, at the end of the exam the potential buyer must determine whether or not they can live with the problems found. If they can live with the problems, they buy the horse. The veterinarian will often provide a letter describing the results of his exam after it is completed.
The exam is divided into three parts: the physical exam, the lameness exam, and additional tests including x-rays and blood and drug tests. The first two parts take about an hour to perform. During the physical exam the doctor listens to the heart, lungs and intestines, takes the temperature of the horse, checks the eyes and teeth, and will usually give you an estimate of the horse’s age. If the horse was raced and is tattooed under the upper lip, it is much easier to determine his age.
The balance of the time is spent on the lameness exam. The veterinarian palpates the horse over his entire body, looking for pain, heat, or swelling. He palpates the back along the spine and muscles to detect any back pain. Each leg is palpated top to bottom. Each joint in each leg is evaluated for increased joint fluid or pain on flexion. The tendons and ligaments in each leg are evaluated for pain on palpation.
Each hoof is also examined. The doctor will pick the feet out and apply a hoof tester to the sole of each. A hoof tester looks like a big pair of pliers. It allows the veterinarian to apply point pressure to specific areas along the sole of the hoof. If the horse has a sore spot in the sole of the hoof, he will try to pull away when pressure is applied.
Once the hooves have been inspected, the doctor performs flexion tests on each leg. Flexion tests involve flexing a joint for a period of time. Then the horse is trotted off. If the horse limps in the first few strides, that is considered an indication of soreness in that area. Veterinarians perform individual flexion tests on the knee and fetlock joints in the front legs, while they typically only test the hocks in the hind legs. This is because the hind legs in horses are built in such a way that if you flex one joint, all the joints are flexed so is difficult to evaluate individual joints.
Following the flexion tests, the horse is usually either tacked up and ridden or put on a lunge line. Then the horse is asked to trot and canter in both directions. Again, the doctor is looking for signs of lameness.
The third part of pre-purchase involves any blood tests and x-rays which may be helpful in discovering sources of illness or lameness. In the majority of pre-purchase exams, the front hooves are x-rayed. This is to determine if there are any changes in the navicular bone. The doctor is looking for changes that might be typical of navicular disease or if there are any indications of ring bone or problems in the coffin bone. If during the lameness exam another area shows abnormality, that area will also be x-rayed. The other most common area to x-ray is the hocks. Many performance horses develop arthritis in the hocks. While such arthritis does not mean the end of the horse’s athletic career, its presence, called bone spavin, is an important factor when making a buying decision.
The potential buyer may also elect to have blood tests run on the horse. Two of the simplest tests to run are a complete blood count, which checks for anemia and infections, and a chemistry profile, which checks for indications of liver, kidney, or muscle disease.
The veterinarian may also run a drug screen. This tests for many of the drugs used to mask symptoms of lameness or to sedate. An unscrupulous seller might use a sedative drug to present a picture of a calm horse or a pain medication to mask a soundness problem in order to fool a potential buyer. The drug screen at present is somewhat cumbersome because the results are often not available for several days and don’t show every type of drug available.
The pre-purchase exam is an enlightening and valuable tool, but it’s important to remember that this is a piece of the decision-making process and not a pass/fail situation.
Dr. Douglas Novick is an equine veterinarian serving the Silicon Valley area of California. He focuses on treating Western and English performance horses, including hunter/jumper, dressage, endurance, reining, roping and pleasure horses. See more of Dr. Novick’s articles and videos at www.novickdvm.com.