Equine Postural Stability Device

The arsenal of portable technology equine veterinarians can carry and use in the field just keeps getting bigger. Researchers recently determined that portable media device (PMD) that straps to a horse’s back is just as accurate as pressure force plates for measuring equine postural stability in certain cases.

Lameness and neurologic disorders can impact equine postural stability—how a horse holds himself up in a standing position. In both humans and horses, researchers have noticed that individuals showing postural instability are more likely to fall, have musculoskeletal pain, and/or experience reduced neurologic feedback, making them less able to control their gaits.

Measuring postural stability can not only help diagnose certain disorders, but also give insight about how treatment is working over time, said Valerie Moorman, DVM, PhD, Dipl. ACVS-LA, assistant professor of equine surgery and lameness at the Colorado State University College of Veterinary Medicine and Biomedical Sciences Equine Orthopaedic Research Center, in Fort Collins.

By using a more convenient, more readily available, and far less expensive handheld device, more veterinarians—and more horses—can benefit from the knowledge gained through these postural stability measurements, she said.

Study Setup and Results

In their recent study, Moorman and colleagues applied a PMD mounted at the top of a surcingle to seven healthy horses. They took at least five postural stability readings for each of four difference stances in each horse:

  • A normal square-standing stance;
  • A stance with the two front legs placed closer together (previous research suggests this causes horses to sway more side-to-side, but not front-to-back);
  • A normal stance five minutes after sedation; and
  • A normal stance 10 minutes after sedation.

They compared the PMD readings with those from a force platform and found that they were very similar, Moorman said. With both devices, they could confirm that the stance condition caused changes in how the horse balanced himself, with more or less swaying—front-to-back and/or side-to-side—and shifting of the center of gravity.

The study allowed them to validate the PMD as a reliable tool in healthy horses, she said. The next step is to test its ability to detect issues in lame or neurologic horses to see if it is as useful as a force platform.

Equine Postural Stability in Practice

“Postural stability has been described in horses as early as the mid 1990’s using a stationary force platform,” Moorman said. “The PMD would be a tool that I would recommend for use by a veterinarian (after future studies confirm it). It could potentially give the veterinarian another way to assess a horse following a specific treatment. Changes in postural stability have been reported in both neurologic and lame horses, and may be useful in monitoring horses following treatment for either type of disorder.”

The study, “Evaluation of a portable media device for use in determining postural stability in standing horses,” was published in the American Journal of Veterinary Research.