Researchers Use Models to Learn Why Equine Bodies Break

Dealing with equine injuries comes with being a horse owner. Some mishaps are more severe than others--such as when Barbaro suffered a catastrophic injury in the 2006 Preakness Stakes--and leave equine enthusiasts asking, "Why?" According to one physical therapist, veterinarians might soon be able to start answering that question thanks to a relatively new technology making an entrance into the horse world.

At the 2011 Florida Association of Equine Practitioner's Annual Promoting Excellence in the Southeast Convention, held Sept. 29-Oct. 2 in Amelia Island, Fla., Michael Torry, PhD, associate professor in Illinois State University's Biomechanics Research Laboratory, discussed the new technology and what it's helping researchers understand about equine injury and rehabilitation..

Technology in Action

For an example of how computational models are used in research, take a look at Torry's recent study, "Relationship between muscle forces, joint loading, and utilization of elastic strain in equine locomotion," which evaluates the equine fetlock joint.

"Understanding how injuries occur is not as easy as it sounds in either the human or the horse," Torry said. "For instance, we either have healthy horses to work with or we have injured horses, and it is not always clear exactly how the injured horses went from being healthy to injured."

Torry explained that "computational modeling" (examining hypothetical injuries on a computer; see sidebar for "Technology in Action") is a relatively new technique for understanding injury mechanisms: "Modeling allows us to understand and investigate forces and loads occurring in the subjects that we cannot otherwise measure easily or noninvasively. Modeling, when appropriately validated, also allows veterinarians to simulate and investigate 'what if' scenarios."

Computational models allow researchers to determine what the consequences are if, for example, a muscle is 25% or 50% weaker or stronger than it typically is.

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"Clinically, we often know that a horse is weak, but we don't how much weakness makes a difference in how that limb functions," noted Torry. "This type of model can help us answer questions like, 'What if a tendon or ligament is ruptured? How would performance or function be compromised? What structures could compensate and what structures might be more vulnerable to further injury?' "

This type of model helps bridge the gap between what we know in a healthy, live horse and what might be the cause of the clinically relevant diagnoses (such as lameness) in an injured horse. Models can give veterinarians a better idea of what factors are most important on the path from healthy to injured or from injured to fully rehabilitated.

Torry added, "We need to know exactly how the injuries occur step-by-step because it is hard to prevent injuries when we don't know what is going on."