Allen said AMG won’t replace lameness examinations, including diagnostic analgesia and imaging., but it could be another tool to help vets diagnose and monitor hind-limb PSL injuries. | Photo: The Horse Staffk

There’s a new way for veterinarians to assess injuries to the upper (proximal) portion of horses’ hind-limb suspensory ligaments, which are notoriously difficult to assess. Veterinarians recently assessed acoustic myography, or AMG, and determined it could be useful for evaluating function of this ligament, which could mean more straightforward diagnoses, treatment recommendations, and monitoring of these injuries as they heal.

Study author Kent Allen, DVM, Cert. ISELP, of Virginia Equine Imaging, in The Plains, explained that imaging advancements have made it easier to visualize proximal suspensory ligament (PSL) structure but evaluating its function (especially during healing) has remained difficult. He recently worked with a research team—including Jillian Costello Chavers, DVM, who now owns and operates Magnolia Sport Horse Equine Lameness and Imaging, in Ocala, Florida, and colleagues from the University of Copenhagen, in Denmark—to test the modality’s potential for use in horses, and he described the team’s results at the 2018 American Association of Equine Practitioners Convention, held Dec. 1-5 in San Francisco, California.

The suspensory ligament—like all ligaments, which connect bone to bone—facilitates energy storage for movement. A small amount of muscle fiber in the structure provides tension. Veterinarians and researchers had long theorized that AMG—which measures how muscle and ligament fibers move—could help in lameness evaluation. They couldn’t test whether it had practical use, however, until scientists developed an appropriate tool. In 2013, Adrian Harrison, DPhil (Cantab), IVH, finally developed an effective AMG unit (marketed as the CURO), which essentially allows veterinarians to “listen” to the horse’s tissues. The research team evaluated this unit in their study