A lame horse risks being euthanized because the condition may have progressed beyond the point of responding to treatment.
But MU veterinary researchers have developed a method that, through early detection, could save a substantial number of injured horses. Tests show that the MU technology dubbed the Lameness Locator can be more accurate than traditional ways used by equine veterinarians to detect injury.
“Lameness often goes undetected or undiagnosed entirely, which can cause owners to retire horses earlier than needed, simply because they cannot figure out why the horses are unhealthy,” said Kevin Keegan, lead developer of the Lameness Locator and a professor of equine surgery in the College of Veterinary Medicine. “If veterinarians can detect lameness earlier, before it gets too bad, it makes treatment much easier.”
For millions of years horses were prey, and those that showed physical weakness were singled out for attack. The ability to conceal injury was an evolutionary advantage for horses. That’s why injured horses try not to limp and don’t whimper like dogs.
The genetically ingrained survival strategy has a downside: Spotting symptoms of a horse’s injury can be difficult for veterinarians.
Lameness is the most common ailment of horses, occurring when their gait is abnormal. The cause might be an inflammation of a hoof, pulled muscle, bone fracture, neurological disorder, compensation for an injury in another part of the body, or some other condition.
The traditional way to detect injury is by observing a horse’s stride for leg favoritism. But the pitfall is the method’s subjectivity. “Veterinarians can be biased about what they see,” Keegan said.
The Lameness Locator, now in commercial use, places small sensors on the horse’s head, right front limb and near the tail. The sensors monitor and record the horse’s torso movement while it trots. The recorded information is transferred to a computer or mobile device and compared against databases recorded from the movement of both healthy and lame horses. The computer is able to diagnose whether the animal is symptomatic.
In a recent study published in the Equine Veterinary Journal, Keegan and co-author Meghan McCracken, an MU equine surgery resident, explain how they induced lameness by fitting special adjustable shoes on horses. The horses were monitored by the Lameness Locator and observing veterinarians. If no lameness was detected, the shoes were adjusted to further affect gait. The process was repeated until both the Lameness Locator and veterinarians noticed symptoms.
Keegan and McCracken discovered that the sensors device identified lameness earlier than veterinarians nearly 60 percent of the time.
The device was successful nearly 70 percent of the time when the lameness occurred in the hind legs. Keegan attributed the outcome to the sensors’ high sensitivity levels.
The Lameness Locator “samples motion at a higher frequency beyond the capability of the human eye and it removes the bias that frequently accompanies human subjective evaluation,” Keegan said.
“Having an objective way to accurately quantify and assess lameness is helping us help equine patients,” McCracken said.