The prepurchase exam reports the physical findings and limitations present in a horse at the time of the exam. Quality of performance is not a question. That is the business
of the agent, the owner, the trainer, and the buyer. Obviously, a prepurchase exam cannot tell you if a given horse can jump a Grand Prix course, place at an NCHA cutting, run a
mile, or cross a bridge over a river. Horses in the upper echelon of price or competitive level that already have an established record will commonly have some degree of wear and
tear and some limitations may be acceptable and treatable.
Seasoned trainers and agents who look at horses in Europe, Mexico, or at the big sales in the United States expect a full set of x-rays to be available. In addition, during the
prepurchase exam the horse may be observed under saddle in all gaits, up and down a slope and over low jumps, or tacked up and collected in a dressage maneuver. The standard
musculo-skeletal exam with flexions and trotting in circles is repeated before and after the exercise. Some trainers may request ultrasounds of suspensory ligaments and tendons
if there is any question of a subtle lameness, especially in the hind legs, but one World Cup level trainer stated that she no longer requests suspensory ultrasounds of the high
level horses she buys. The younger ones are not likely to have lesions yet and if the older campaigners have sensitivity, lameness, or swelling, she doesn’t buy them.
Prepurchase exams on thoroughbreds and warmbloods may also include endoscopic exam of the larynx for partial paralysis of the arytenoids cartilages that would reduce performance.
An agent presented Humphrey to a veterinary hospital in Virginia for a pre-purchase examination. Humphrey was a gorgeous, tall, dark bay seven-year-old thoroughbred cross gelding
and his proposed use was for hunter equitation. His current owner had only owned him a month, planning on resale, and Humphrey had been worked hard in the last 10 days.
Humphrey’s general physical exam was mostly normal but Humphrey’s limb conformation was straight, he was slightly narrow through the stifles and hocks and he toed out a bit on the
right hind. He had some sensitivity to his lower back on the right side and his hock flexion test was positive on the right. He was worked up and down a hill and over some low fences
under saddle and his hock flexion improved, though it was still not normal. The examining veterinarian was concerned about Humphrey’s right hind leg and advised a week of light flat
work since the horse had been shown extensively during the previous 10 days.
One week later, Humphrey was reexamined. The examiner described improvement and decided that Humphrey’s prior musculoskeletal soreness was from the sudden intense use. X-rays were
taken of the knees, front fetlocks and the hocks and were all within normal limits. Blood was drawn for a complete drug screen and a Coggins test. Ultrasound was not requested or
performed. The final diagnosis stated: “suitable for hunter equitation.” On this advice, the agent informed her client that Humphrey would be a good choice. At that moment in time,
perhaps he was.
Over the next two years, Humphrey demonstrated back and right hock pain and required treatment that included hock injections, mesotherapy, chiropractics and pain medication.
In one final year, Humphrey had complete failure of the support structure of his right hind fetlock. An ultrasound showed that the medial branch of the RH suspensory apparatus was
torn and swollen, the lateral branch mildly damaged, and the proximal suspensory mildly inflamed. His fetlock dropped too far towards the ground at every step. Six months of
confinement, supportive shoeing, injections of cortisone, daily icing and wraps, and oral NSAIDS could not improve the chronic, irreversible damage. Shock wave therapy was not
considered an option. Humphrey was not even comfortable walking around his paddock.
Would an ultrasound at his prepurchase exam have demonstrated an early suspensory lesion? Perhaps not, as there was no indication of sensitivity, swelling, or loss of support in
the fetlocks reported by the examiner.
A prepurchase exam does not predict the future performance or the resale value of a horse and it cannot predict whether a given horse will perform well for a new owner. The
prepurchase exam should prevent a new owner from purchasing a horse that is not physically able at the time of the exam to perform its proposed use in comfort. Unfortunately for
Humphrey, his comfort would only last for a moment in time.