Shockwave therapy has a positive and negative phase. The positive phase produces direct mechanical forces, whereas the negative phase generates cavitations and gas bubbles that subsequently implode at high speeds, generating a second wave of shockwaves. It uses high peak pressure followed by low amplitude, short duration, and short rise time. They have a single pulse, with high-pressure amplitude (0-120 MPa) and a wide frequency range (0-20 MHz). Whereas ultrasound waves have approximately 1000 times lesser peak pressure than that of a shockwave. Shockwaves are low-frequency pressure disturbances that travel rapidly in three-dimensional space, associated with a sudden rise from ambient pressure to their maximum pressure. Significant tissue effects include cavitations, which are consequent to the negative phase of the wave propagation.
The whole process does not produce any thermal effect, it promotes revascularization, stimulating proliferation and osteoprogenitor differentiation, increases leukocyte infiltration, amplifies growth factor and protein synthesis to stimulate collagen synthesis and tissue remodeling.
The patient is assessed by the physiotherapist during his first visit to confirm that he is an appropriate candidate for shockwave therapy. The treatment is started by applying gel on the treatment area. The applicator or therapy head is directly placed on the area. A medium of gel is required for the transmission of the waves through the patient's skin. The parameters are set and the intensity is applied according to the comfort of the patient (there is no standardized protocol for the treatment of musculoskeletal conditions). It can be used in conjunction with treatment-specific exercises, activity modification. Depending on the results, the patient is advised to take the shockwave therapy once a week for 3-6 weeks.