The quest to discover, deliver and optimize solutions that utilize the body’s own healing capacity to improve the lives of both animals and humans has never been more of a central focus at the C. Wayne McIlwraith Translational Medicine Institute (TMI), and a group of scientists from the affiliated Orthopaedic Research Center (ORC) are driven to accomplish just that. Seeking to improve orthopedic rehabilitation strategies, the researchers are navigating unchartered scientific territory to bring widely utilized technology for human patients to horses recovering from injury, specifically blood flow restriction (BFR) training. Initially utilized to rehabilitate military personnel following limb-salvage procedures or traumatic blast injuries, the technology has become a key rehabilitative tool for a variety of human orthopedic conditions and its clinical use has transformed conventional rehabilitative approaches previously limited by exercise restriction.

Through the application of a pressurized tourniquet to temporarily reduce blood flow to an exercising limb, human patients undergoing BFR training are able to increase strength using light weights or low-intensity exercise (cycling or walking). Putting the limb under pressure through tourniquet application while lightly exercising has been documented to beneficially stimulate the body’s natural cell signaling pathways that stimulate healing, strength and ultimately function. With the ability to strengthen surrounding musculature without exposing healing tissue to traditional damaging loads, human physical therapists are able to more safely and efficiently prepare tissues to return to work. Inspired by its promising results in humans, a team of equine researchers made up of Equine Sports Medicine and Rehabilitation clinicians, surgeons, imaging experts and exercise physiologists, Sherry Johnson, David Frisbie, Melissa King, Kurt Selberg and Adam Chicco set out to investigate it’s use in horses. They recognized that a BFR technique similar to that utilized for human injuries would have the potential to greatly enhance the health, welfare and general well-being of a vast number of horses that experience similar injuries.

To this extent, the group recruited leading human BFR experts: human BFR researcher Dr. Brian Noehren (University of Kentucky), BFR physical therapists of Owens Recovery Science (ORS) and surgical tourniquet specialists Delfi Medical Innovations, Inc. (Delfi) to help design, implement and troubleshoot preliminary equine investigations that incorporated novel pressure-specific BFR settings not previously used in horses. Once the group confirmed that the Delfi BFR cuff for human use stayed in place during equine walking exercise, they investigated short-term effects on muscles key to forelimb locomotion. Following 10 days of walking exercise, all horses demonstrated muscle oxidative capacity increases consistent with strenuous exercise, consistent with beneficial effects reported in humans. With exciting preliminary results, their subsequent research proposal to investigate BFR’s effects in all musculoskeletal tissue types ultimately garnered recognition as the highest-scoring proposal submitted for the inaugural TMI Translational Acceleration Program (TAP), funded by Leslie and John Malone to support the acceleration of promising projects with translational potential to people. Through funding provided by this charitable donation, the team will be the first research group to define BFR’s effects on equine tendon, muscle, bone and cartilage. These findings will directly impact the use of BFR not only in horses, but humans as well due to the translational similarities between the two species. Such knowledge will ultimately help guide BFR’s safe and efficacious use in the rehabilitative setting across species.

With such a strategic team of experts now assembled to continue equine BFR research, clinical use and future collaborative projects, this team is dedicated to the advancement of this exciting, novel rehabilitation technology that otherwise wouldn’t be possible in horses. The group has since focused efforts on developing and validating a BFR cuff specific for veterinary use. Given that upwards of 70% of actively competing horses suffer injury at some point during their careers, this technology that utilizes the body’s own capacity to jump-start healing will impact a significant number of horses. The demand to improve rehabilitation for both horses and humans has never been higher, and this team is excited to continue this translational quest.

Pictured above, Dr. Sherry Johnson of the C. Wayne McIlwraith Translational Medicine Institute applying BFR training to a horse while walking on an exercise treadmill. Advanced tourniquet sensor technology developed by Delfi Medical Innovations, Inc. to deliver patient-specific pressures during exercise in order to maximize comfort and therapeutic outcome is considered the standard of care in people, and was therefore utilized by this this research group.