Extracorporeal shock wave therapy (ESWT) has been used in human medicine for decades, primarily to break up bladder stones so that they could be passed without surgery. ESWT has been used on the equine athlete for the past 20 years, especially for treatment of arthritis, tendon and ligament inflammation and/or tears, navicular syndrome, spine impingements, stress fractures, avulsion fractures, sacroiliac disease and muscle damage.
New studies are showing improvement in wound healing using ESWT. It has also been shown to weaken bacterial cell walls, which may be helpful in bacterial skin infections or even bacterial infections of the bone or muscle.
The effects of ESWT can be seen both clinically and at a microscopic level. Studies have shown that ESWT decreases inflammation, speeds healing, causes new blood vessel formation, improves fiber alignment in tendon repair, increases cellular bone production for faster bone healing and recruits stem cells to the injured tissues. It also acts to relieve pain.
There are two main types of shock wave units. Fox Valley Equine Practice has a ‘focused’ unit, so that a particular tissue depth and area can be treated precisely. ‘Unfocused’ units can also be useful, but they use a different energy form and tend to be less specific, and many insurance companies won’t cover the cost of treatment with the unfocused units.
The energy level, number of shocks, and depth of penetration vary, depending on each individual condition being treated. Treatments generally consist of 500 to 2000 shocks every few weeks for three treatments, depending on clinical signs and evident improvement. Many ask if the treatment is painful. At the energy levels we use to penetrate tissues, the horse can definitely feel it, and it can be somewhat painful during the typical 10 minute procedure. Sedation is used to keep the patient comfortable during the treatments, however, the treatment itself has an analgesic (pain reducing) effect soon afterwards.