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. 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.