Any number of health and soundness factors come into play when making a prepurchase examination of a horse. Yet one of the more difficult areas in evaluating horses for purchase is the potential that lameness concerns and foot problems may have on future success.
To provide ideas on evaluating the equine foot, American Farriers Journal editors sifted through a half dozen scientific papers dealing with prepurchase examinations. The foot and leg guidelines found here were taken from papers dealing with prepurchase examinations that were presented at several recent American Equine Practitioners Association annual meetings.
Jerry Black finds it's essential to know how a horse will be used when evaluating feet during a prepurchase examination. The equine veterinarian at the Pioneer Equine Hospital in Oakdale, Calif., pays close attention to the hocks and stifles while evaluating cutting and reining horses.
He says larger Quarter Horses have traditionally had a relatively high incidence of navicular disease due to foot size, straight pastern angulation and large muscle mass. While significant strides have been made in breeding a more modern type of Quarter Horse with better overall conformation, Black says attention must be paid to the principles of distal limb conformation and balance.
With team roping horses, he finds added stress is placed on the distal forelimbs while turning the steer or positioning the horse to rope the heels. The result is a relatively high incidence of degenerative arthritis in the distal joints. Bone spavin is also a common occurrence due to body type and performance stress.
With barrel horses, he looks at foot size, conformation and balance since concussion can be severe. Significant stress is also placed on the hindlimbs while propelling the horse around the barrel at a high rate of speed.
Jumpers, Dressage Horses
Daniel Marks of Santa Fe, N.M., wants to know the type and quality of shoeing a horse has previously had when examining jumper and dressage horses for possible purchase.
He says many factors must be considered with each horse before reaching a prepurchase decision. As an example, he cites 17 relevant factors that need to be considered with a horse that has an oddly shaped or small foot:
1. History of previous lamenesses.
2. Conformation that may relate to the foot.
3. Musculoskeletal pathology in the leg.
4. Shape and quality of the hoof.
5. Wear of the shoe or hoof.
6. Shoeing techniques that have been used.
7. Response to hoof testers and percussion.
8. The flight of the leg, foot landing and breakover.
9. Evidence of lameness.
10. Other tests such as toe elevation prior to trotting.
11. Radiographic findings.
12. The vet's knowledge as to the intended use of the horse.
13. Consideration of the buyer's circumstances.
14. Quality of the farrier, as a specialized farrier might be required to maintain difficult feet.
15. Schooling surface.
16. Probable show schedule.
17. Show ring footing.
Marks says slight differences in size and shape of a horse's feet are common and not necessarily abnormal. As an example, a club foot can still be functional, depending on radiographic changes and shoeing techniques that are used.
"Foot lameness is usually more apparent in hard going and frequently is accentuated by circling," he says. "This ranges from a minor sole bruise to irreversible navicular disease."
If a horse is shod and managed well, Marks says mild cases of navicular disease may be tolerable for pleasure riding and easy competition. But tackling big jumps is not compatible with navicular sensitivity.
"Dressage riding surfaces are forgiving of foot problems, but a tendency to shorten the stride is not a good thing in a dressage horse," he says. "Corners, zigzags, extended trot and tempo changes are movements where navicular disease may degrade performance.
"Hunters can compete with mild navicular disease, provided that the gallop stride is naturally long and the going is forgiving."
Marks finds horses with caudal hoof pain often suffer from a laminar tearing rather than an internal foot problem. Pedal osteitis and deep bruising may sometimes reside in the subchondral bone of the third phalanx. Sidebone can also be a concern, as can navicular spurs caused by uneven hoof loading.
"Laminitis and founder have so many variables that each case must be evaluated on its own merit," he says.
Marks maintains that more than 50 percent of all jumpers and Grand Prix dressage horses have an inflammation of the distal intertarsal and tarsometatarsal joints.
"While this requires treatment for maintenance of peak performance, the condition is usually bilateral but not symmetrical," he says. "A combination of shoeing, management and medication generally is successful."
Sue Dyson of the Centre for Equine Studies in Kentford, England, says the majority of elite show jumpers are naturally well-balanced, loose-moving warmbloods. Reaching the Grand Prix competition level at 8 or 9 years of age and continuing to compete until up to 20 years of age, these horses are generally well proportioned but vary in conformation.
"Yet the feet are a notable exception," she says. "The feet of warmblood horses are often not well conformed nor well proportioned in size and shape relative to the horse's body weight.
"This can be regarded as a conformational fault, sometimes compounded by poor foot trimming. Greater attention to correct foot balance may help prevent some lameness."
Dyson says horses with a predominance of Thoroughbred breeding do better than other breeds in this combination of dressage, show jumping and cross-country work.
When it comes to examining these horses, Dyson says foot conformation, trimming, shoeing techniques and shoe wear are critical.
Along with other common causes of acute lameness in event horses, she finds foot soreness, binding nails, trimming and shoeing problems must be considered in evaluating the potential problems of these horses.
Paul Wollenman of the Palm Beach Equine Clinic in Wellington, Fla., likes a big cupped hoof with a short toe and good heel in polo ponies.
"Over the past 5 years, less chronic heel pain has occurred in polo ponies due to farriers paying special attention to toe length, breakover and hoof growth," he says.
When examining horses with underrun heels, different sized feet or lameness concerns that show during an examination, he definitely wants to see radiographs.
When evaluating horses for competitive trail riding, endurance riding or marathon driving, Matthew Mackay-Smith suggests paying close attention to the feet.
The White Post, Va., equine veterinarian and member of the American Farriers Journal International Equine Veterinarian Hall of Fame, says mismatched hooves can be a serious concern with endurance type horses.
In evaluating soundness, he expects to find good feet with thick, tough, flinty hoof walls. There should be a moderate slope to the hoof with deep open hooves that give the impression of an oversized foot with matching hooves.
Hugh Behling says American Saddlebreds aren't susceptible to greatly increased incidences of lamenesses. This is due to the elevated and shortened stride length or lack of extension on the anterior phase of the foot flight pattern.
When making prepurchase examinations, the Simpsonville, Ky., equine veterinarian finds contracted heels, sheared heels, quarter cracks and hoof wall separation are typical foot concerns.
Except for pleasure classes, he says there are no restrictions on using pads, double-nailing techniques, lead weighting, clips or bands on shoes. It's also common to find large hoof wall defects filled with acrylics.
"The incidence of lamenesses due to diagnosed navicular pain is similar to that in the Thoroughbred population," he says. "There are bloodlines that seem to have a high incidence for one of the forefeet having a dished foot."
He finds the proximal one-half of the hoof wall parallels the dorsal border of the third phalanx very closely and deviates distally. This is often found with pastured horses that haven't been shod or trained.
Behling says an understanding of shoeing methods will help veterinarians minimize the frustration of examining Saddlebreds.