My favorite aspect of offering shockwave treatment is the incredible results. Shockwave is a great addition to the arsenal of treatments that we can provide for a variety of injures. In the last few years, our ability to diagnose conditions has improved greatly (such as digital x-rays, 3D ultrasound, MRI), but we were still limited in our treatment options (rest, steroids, shoeing–to name a few). Shockwave gives us a great treatment option that is minimally invasive with proven results.
Extracorporeal shock wave therapy (ESWT) is an emerging new technology for treating musculoskeletal problems, soft-tissue and bone injuries in horses. ESWT is non-invasive and used to stimulate healing so horses return to a level of full soundness and useful activity without recurrence of disease. It actually heals tissues, not just suppresses pain and inflammation.
How is the wave produced?
A shockwave is a pressure wave – any action that displaces its surrounding medium is a shockwave. The ripple created when a stone is thrown into a pond is a shockwave. It has nothing to do with “shocking” or electricity. The shockwaves used in equine medicine are generated in a fluid medium inside a transducer head and are then transmitted readily through skin, fat, and muscle. The high energy waves are focused within the transducer head so that the shockwave can be directed to the precise area of the injury. When shockwaves hit an area of higher acoustic impedance, such as bone, the waves slow dramatically and a large amount of energy is released into the surrounding tissue.
From outside the body (extracorporeal), the machine generates high-intensity shock or pressure waves, which pulse to a specific site within the injured tissue. Though its actual mode of action is still in dispute, it stimulates and accelerates the healing process, essentially combining an immediate analgesic effect with a reduction in inflammation, creating new blood vessels in soft tissue and regeneration in bone.
Initially used to treat musculo-skeletal problems and kidney stones in humans, this same shockwave technology has been found to be highly effective in treating many lameness and musculo-skeletal problems in horses. Using hydraulic pressure, soundwaves are generated by the machine that penetrate the horse’s tissue, where they result in the release of beneficial bio-chemicals and stimulate the growth of a new blood supply to injured areas, as well as providing pain relief.
Shockwaves are high-energy sound waves, which are transmitted to the affected body part. There, they trigger the body’s natural repair mechanisms by stimulating immune-competent cells. Thus, a lasting healing response is achieved without any side-effects.
Shockwave therapy is similar to ultrasound because shockwave equipment sends a wave-like pulse into the tissue from a position outside the body. The energy of the acoustic (sound) wave produced by shockwave equipment is approximately 100 times higher than the energy of the acoustic (sound) wave produced by diagnostic ultrasound units used in equine veterinary medicine. While the acoustic (sound) wave produced by diagnostic ultrasound equipment does not distort body tissue as it enters, travels through, and then rebounds back out of the body tissues to be picked up by the ultrasound probe; the higher energy acoustic (sound) wave produced by equine shockwave equipment does distort the denser body tissues upon initial contact and again at rebound. The “shockwave” wave or pulse compresses denser body tissues such as ligaments, tendons, and bone on its initial journey into the body and then as the “shockwave” wave or pulse recedes these denser body tissues rebound and expand at the cellular level. So, while ultrasound waves rebound without tissue distortion and provide the viewer with a computer generated visual image of body tissues, “shockwave” waves do distort the denser body tissues and thereby essentially “massage” the denser body tissues at the cellular level. This micro-manipulation of the denser body tissues such as ligaments, tendons and bone by the shockwave acoustic (sound) wave stimulates neovascularization (growth of new blood vessels in tissue) and the production of fibroblasts and osteons (cells that heal tendon, ligament and bone). The cellular “deep tissue massage” produced by shockwave therapy also provides some degree of analgesia (pain control), improves healing rates in skin wounds, and produces improvement in infected injury sites.
Shockwave therapy has been shown to:
- Recruit stem cells locally so that the healing is most like the original tissue (less scarring)
- Stimulate new bone growth
- Increase cell permeability and stimulate the release of a cascade of healing and growth factors that contribute to the natural healing process
- Stimulate stem cells in the animal’s body to be directed to the treated area
- Cause neovascularization (an ingrowth of new blood vessels)
- Stimulate fibroblasts, the cells that generate new connective tissue
“ESWT utilizes high-pressure sound waves focused at a very small, specific site within the body to aid healing of muscular, tendon, and bone conditions,” explains Scott McClure, DVM, PhD (veterinary physiology), Dipl. ACVS, assistant professor in the Department of Veterinary Clinical Sciences at Iowa State University. Based on the same technology whereby lithotripsy breaks up kidney stones in humans, ESWT has been applied in horses to stimulate blood flow and bone remodeling, and to repair ligaments. “The pressure waves can be focused at tissue within the body; the tissue between the surface and focal point is not affected,” McClure says.
Shockwave therapy constitutes a new modality for dealing with refractory conditions, by stimulating the animals natural repair mechanisms.
ESWT is a non-invasive treatment that can speed the healing of many types of orthopedic and soft tissue injuries and conditions. It has been used in Europe in human medicine to treat tennis elbow, plantar fasciitis (heel pain), rotator cuff injuries, diabetic ulcers, calcifying tendonitis of the shoulder, femoral head necrosis (hip degeneration), non-union fractures, wounds, burns, osteomyelitis (infection of the bone) with draining tracts, and myofascial pain to name a few. New research has shown potential applications in treating periodontal disease, infected wounds, and to help speed fracture healing and reduce the incidence of non-union fractures. It has been approved by the U.S. Food and Drug Administration for use in people to treat plantar fasciitis and tennis elbow that fail to respond to six months of conventional therapy.
WHAT CAN SHOCKWAVE TREAT IN HORSES?
Shockwave therapy has been successfully used to treat many soft tissue and bony problems, both acute and chronic. These include, but are not limited to:
- Suspensory ligament tears, strains, and avulsion fractures
- Arthritis, joint pain
- Bowed tendons
- Bucked Shins
- Deep digital flexor tendon injuries, including those within the hoof
- Navicular syndrome
- Ringbone (High and Low)
- Back pain, Neck pain
- Muscle tears and strains
- Ligament and tendon tears and strains
- Improve large or chronic wound healing
Shockwave therapy has been used in the U.S. in veterinary medicine for approximately 12 years. It has been used successfully to treat animals with both acute and chronic soft tissue injuries, bone and joint disease, and back pain. It has definite benefits, but the therapy is most effective when used in conjunction with other treatments such as medical treatment, corrective surgery or shoeing, and rehabilitative physical therapy.
DOES SHOCKWAVE WORK ON EVERY CASE?
No, there is no treatment that is successful in every case. Shockwave therapy is one of the most exciting therapies to become available to veterinary medicine in quite some time. It is extremely important to have an accurate diagnosis and a clearly defined area of injury in order to direct the shockwave to the appropriate area.
ARE ALL SHOCKWAVE MACHINES EQUAL?
Absolutely not. There are several machines currently marketed as shockwave machines that do not generate a true shockwave. They generate what is called a ballistic or radial wave. The physics of this type of wave are completely different from that of a true shockwave. A ballistic or radial wave is created when a projectile is rapidly accelerated by compressed air – it looks like a small jackhammer. The problem with this type of wave is that all of the energy is deposited at the skin, and the energy drops off rapidly as you move away from the skin. The result being that unless the injury is at the skin, the injured area is not receiving the necessary energy to help the healing process. Additionally, since the wave is not focused with this type of machine, the entire area around the treatment site is receiving the wave, which can potentially have harmful effects.
WHAT EQUIPMENT DOES TOTAL EQUINE VETS USE? (Or what vet should I choose?)
TEVA uses a focused, electrohydraulic machine manufactured by Pulsevet. This machine is currently used in 18 different university veterinary hospitals and is largely considered to be state of the art. With this machine, the shockwaves are focused so that they can be directed precisely to the particular area of injury. Additionally, the energy level and the depth of penetration of the shockwaves can be varied to suit the injury. In Virginia, referral facilities offer this service, like the Equine Medical Center and Virginia Equine Imaging. We have decided to bring this treatment on the road and deliver it to your farm.
The VersaTron system manufactured by Saunawave ( www.saunawave.com ) is currently the only electro-hydraulic shockwave equipment designed specifically for use in the equine industry. It is FDA approved. It is the equipment currently in use at the majority of university level research facilities. Other shockwave machines are inferior and unlikely to produce results (that’s why they are cheaper). Consequently, treatment with VersaTron equipment is the most likely method to be subsidized by the major equine surgical medical insurance providers. Yes, horse insurance often covers shockwave, but only if it is done with a VersaTron machine.
WHAT SHOULD I EXPECT DURING AN APPOINTMENT?
Shock wave therapy is not a universal remedy for every orthopedic condition. Based on a definite diagnosis, shockwave may be recommended along with other treatments. Shockwave equipment is relatively expensive and the probes that produce the acoustic waves have a finite lifespan before replacement. Most body sites require between 1000 and 1500 pulses (waves) per treatment session and between two and three sessions at 2 week intervals. Based on an average billing structure nationwide, most veterinarians charge about $0.3 to $0.4 per pulse or $300 to $400 per thousand pulse session. Some horses require tranquilization.
The treatment is done by saturating the horse’s hair with ultrasound gel and then using a special probe to transmit the generated soundwaves into the horse’s tissue through the skin.
Shockwave therapy is very safe for the horse. Unlike surgical or injectable treatment options, it does not require sterility, prolonged recovery time, or bandaging, and does not present any risk from needle puncture. For hock and stifle problems, as well as sesamoiditis, it can be an excellent option for the owner who wants to avoid joint injections, or the horse who does not tolerate needles well. Although the horse is generally lightly sedated to prevent movement during therapy, the treatment is easily done in the standing horse, does not require clipping of the treated area, can be done on the farm, and takes only 10-20 minutes. Most horses improve quickly with responses being seen in 7-10 days.
Shockwave is a great option for treating several common horse injuries and conditions. It is non-invasive and well-tolerated by horses. It speeds healing and improves the quality of repair of tissue. It is affordable and covered by most insurance plans. Be wary of inferior shockwave devices that cannot deliver proven results.
Total Equine Veterinary Associates is a full service mobile equine veterinary practice emphasizing lameness evaluations and treatments, dentistry and “Performance Tweaking”. They offer annual discounted Wellness Packages and a variety of services, including dog and cat vaccinations on the farm. Call to inquire, Dr Jay Joyce at (703) 505-2320.