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SHOCKWAVE THERAPY
circumstances it is not open to RVL Stewards to apply the Rule.” A shockwave is a high intensity acoustic wave created by a machine which is targeted to a specific location of the body. The waves pass through fluid and soft tissue and affect areas only where there is a tissue change, such as where bone and soft tissue meet. It is still unknown how shockwaves specially stimulate the healing process, but they do reduce inflammation, increase blood flow and promote the creation of new bone. They might also aid in destroying hematomas in tendon lesions, which enables new tendon to be laid down more rapidly. Although the effects of shockwaves from detonated bombs were first noticed during World War II, there was a relatively small amount of interest in using this therapy for human medicine until 1966 in Germany after an experiment with high propensity projectiles. The German Department of Defense financed the research project on shockwaves and in 1971 this mode of treatment was used to splinter kidney stones in humans so they could be passed through the body. The first
Shockwave treatment was introduced to equine medicine in the mid to late 1990s
“Maybe I should have been more familiar with the rules. This kind of therapy is used all over the world and in England cannot be used only on race day” Luca Cumani machines for commercial use were built in the early 1980s and by 1985, had been used for gall bladder stones. Currently, shockwave therapy is the preferred form of treatment for kidney and gall bladder stones, but is also used throughout the world to treat heal spurs and tennis elbow. Scientists are researching whether shockwave can be used to remedy various forms of tendonitis and stress fractures. Shockwave therapy was introduced to equine medicine in the mid to late 1990s for proximal suspensory desmitis and navicular pain. There are two different types of shockwaves: extracorporeal and radial. Radial shockwave therapy (RSWT) is less pressured and therefore, does not penetrate as deeply. “Extracorporeal shock therapy can be a valuable noninvasive mechanism to stimulate healing of some musculoskeletal injuries in horses,” said Dr. Scott McClure, DVM, of Iowa State University in Ames, Iowa. “A major concern of ESWT in horses is the potential for analgesia after therapy.” If analgesia is induced in a horse, it may not experience pain to a varying degree, even to the extent of having no consciousness of pain, and as such could severely increase the amount of damage to the injured area through overuse. Since this increases risk to the horse and his rider, precautions must be taken to ensure the analgesic affect has disappeared once the horse returns to work. “This data indicates a horse should not be subjected to strenuous activities where local analgesia might pre-dispose them to injury
for at least four days after ESWT or RSWT treatment,” stated McClure at the 2003 American Association of Equine Practitioners Convention. McClure and his associates conducted another study presented at the 2006 American Association of Equine Practitioners Convention and published in the July 2006 edition of the Journal of the American Veterinary Medical Association that buttressed his former results. He evaluated nine horses with acute forelimb lameness during seven days of shockwave treatment. “There was significant analgesia after ESWT from eight to 48 hours after treatment,” McClure wrote. “Horses should have limited exercise for a minimum of 2 days after shockwave therapy to avoid potential injury caused by a lack of pain perception. For this reason, racing jurisdictions in the United States and the Federation Equestre International have adopted regulations that require a five-toseven day period after treatment before the horse is allowed to perform.” Shockwave therapy in humans and other mammals has been shown to affect nerve endings and blood vessels, which could contribute to the fleeting analgesic affect. In horses, however, not enough research has been completed to ascertain if this is true. In a study presented at the 2006 American Association of Equine Practitioners Convention, Mauro Verna, DVM, now of La Plata University in Argentina, and colleagues from his residency program at the University of Minnesota used non-focused shockwave ISSUE 12 TRAINERMAGAZINE.com 31