This article was published in modified form in Equus Magazine
A prepurchase exam is an evaluation of the physical well-being and suitability of a horse for a given purpose and a given owner/rider.
Traditionally, a prospective buyer hires a veterinarian to examine the horse he or she wishes to buy, but the veterinarian must work
within the “rights and interests of the seller and the health and welfare of the horse being examined,” according to Harry W. Werner,
VMD, as noted in the November, 2005 AAEP Guardian.
My husband and partner, Dr. Jim Latham, has practiced equine medicine for over thirty years and we have a standard of care for the
prepurchase exam that is comfortable for our practice. Increasingly these days, veterinarians are consulting on prepurchase exams with
digital movies, and x-rays done as far away as Europe, and they must depend on the quality of images and on the ethics and the diagnostic
acumen of distant practitioners. Every veterinarian must establish his or her own standard that fits the circumstances of the practice
and the case in hand.
The first question we ask the buyer is to describe the intended use of the horse and the second, when pertinent, is to ask if they have
actually been on the horse and ridden it in the setting commensurate to their planned usage. We then explain the process and the limitations
of each step of the exam. The monetary value of the horse is not in question.
We like to question the seller on the past history of the horse and its recent use. In general, we avoid a conflict of interest—we do not
perform prepurchase exams on horses currently in our care unless buyer, seller and we ourselves are fully comfortable with the situation.
We prefer both seller and buyer or their representatives/agents to be present for the prepurchase examination. In this era of internet shopping,
that is not always possible.
The prepurchase exam is more than a general physical--we always include auscultation of the heart and lungs and an ophthalmoscopic examination of
the eyes in a darkened stall, as well as examining ears, teeth, skin, and general conformation. Depending on the intended use, a mare may be
inspected for breeding soundness, a stallion for fertility and breeding behavior. The overall behavior of the horse in hand, and under saddle is
observed, if pertinent to the expected use.
A large part of the prepurchase exam involves looking for lameness, subtle changes in a way of moving as well as overt stiffness or limping.
Lameness diagnosis is part science, part art, and a big part observation, in this case by the veterinarian.
The exam is performed with the horse as presented, usually with shoes on.
We then palpate the horse’s neck, back, hindquarters, and limbs, and check for sideways flexion of the neck and dorsi-flexion of the back.
We observe the horse in hand, walking and trotting straight way on a firm, level surface and then as he circles an arena or round pen on a
longe line at all gaits, in both directions. We watch the horse walking up and down a slope. We look for length of stride, symmetry of gait
and action of the fetlocks, head bobbing, and carriage of head and neck. We watch for reluctance to take a lead at the canter, or switching
leads. With performance horses, we prefer to watch the horse under saddle with a professional trainer on board at all gaits, and with jumpers,
we look for reluctance to jump or jumping flat or crooked. We listen to the observations of the trainer on the horse’s ride. The horse is unsaddled.
We then repalpate the back and neck for sensitivity to pressure.
Foot structures are often the source of pain causing lameness in horses. Using hoof testers that look like giant open pliers, the veterinarian applies
pressure at specific points around the soles of each hoof, across the heels, and on the spongy cushion, the frog, in the middle of the foot. Additionally,
we observe the placement of the horseshoes and the break over point, the angle of the hoof compared to the angle of the pastern, and the length of toe and
heel.
Jim palpates the tendons and suspensory ligament down the back of each leg. Next, a handler trots the horse in a straight line while we observe him.
Jim then flexes each limb at specific sites to determine discomfort and increased signs of lameness when the horse is released to trot away after each
flexion. The stress created by bending the joints may reveal a sensitive area. He flexes the knees, the fetlocks, and the hocks.
Jim often x-rays critical areas—the forefeet and the hocks—and more depending on the intended use of the horse. Because horseshoes interfere with the
diagnostic qualities of foot x-rays, the shoes are usually removed prior to the radiologic study. The seller is advised to have a farrier to reshoe the
horse within a few days or to have rubber boots on hand. We consider a minimum number of survey x-rays to be 4 views of each hock-- anterior-posterior
(AP), lateral, and two obliques--and 3 views of each forefoot—AP, lateral, and the skyline navicular view with the sole filled with PlayDoh to remove
shadows from the sulci of the frog--a minimum of 14 films. Clinical findings or the needs of the buyer may dictate further views. Yearling thoroughbreds
moving through the Keeneland sale and now cutting horses in the select Bloodstock sale have a standardized, prescribed set of 32 x-rays produced and banked
prior to the sale and available to prospective buyers.
Jim may ultrasound tendons and suspensory ligament structures depending on the exam, intended use, and the degree of certainty needed by the prospective
buyer. We always offer to pull a blood sample to test for the presence of NSAIDS (pain relieving anti-inflammatory drugs like Bute) that might mask
discomfort during the exam.
Diagnosis of specific lameness discovered during an exam is not a part of a prepurchase exam. The seller of the horse, if present at the time, may
request additional diagnostics including nerve or joint blocks and further examination to determine the precise cause of lameness, but the prepurchase
exam is usually terminated at that point. Invasive procedures are always at the discretion of the current owner. An acute lameness caused by recent
shoe removal or a known injury may put the exam on hold.
Mares possibly intended for eventual reproductive use must have additional examination, with the permission of the seller. The reproductive tract is
both palpated and ultrasounded and the vaginal vault examined. If the mare has a prior reproductive history, the buyer is advised and may request
uterine culture or biopsy. Once again, these procedures must be done with the informed consent of the current owner.
Stallions intended for breeding are usually examined at a stallion station where the capability exists for collection and examination of the semen
for motility, and morphology of the individual sperm. Fertility records may be examined.
The horse is rarely perfect. He may have significant dental problems—sharp points or uneven wear. There may be minor, manageable conformational
limitations. The performance horse may have some degree of arthritis—both clinically and on x-ray. Jim will discuss the need for treatment and
the likely progression of the wear-and-tear conditions he may find. He will discuss the likely complications of resale of the horse at some
undetermined future time. He will comment on the temperament of the horse for the intended buyer, especially when a child may be involved.
Especially with inexperienced buyers we feel an obligation to do more than just report physical findings. Novice horse owners do not have the
knowledge or background to make “informed” decisions without more guidance. For example, we feel that we need to advise against a purchase if it
looks like a bad or dangerous situation for a sound but unruly horse and a green rider or a child unless the buyer understands the need and
uncertainty of future training. It all comes down to suitability; can the buyer reasonably expect the horse to perform at the level of its
intended use.
A written report of the prepurchase exam is produced in detail and provided to the buyer. The decision is always in the buyer’s hands.