Understanding how radial extracorporeal shockwave therapy reduces pain and aids in recovery

Radial extracorporeal shockwave therapy (rESWT) offers non-invasive relief for many painful ailments, including tendinitis, plantar fasciitis, and heel spurs. A handheld device delivers pressure waves through the patient’s skin to the area of injury, which is believed to stimulate blood circulation for faster recovery. It is also possible that the treatment desensitizes pain sensors by overstimulating them.

Though effective in clinical use, the exact mechanism for rESWT’s success remains elusive, and a lack of standardization reduces treatment effectiveness. He et al. tested the output of the shockwave therapy in water to understand how it works in the body and develop best practices for patient care.

Because water has a similar acoustic impedance to human tissue, it functioned as a convenient, transparent medium to investigate the therapy.

“We examined the pressure waves rESWT creates under different settings using a needle-type hydrophone, which can detect and measure small changes in pressure,” said author Xiaodong Chen. “We used a high-speed camera to visualize the cavitation bubbles created by the rESWT, providing a visual representation of the therapy’s impact at the microscopic level.”

Using computer modeling informed by their experiment, the team identified the key parameters, like location, pulse frequency, and energy, and their effects on the resulting shock waves.

“The ability to determine the best parameters for shock wave therapy through predictive models can improve the overall efficacy of the treatment and lead to better patient outcomes, reduced recovery times, and a lower likelihood of needing repeat treatments,” said Chen. “The insights from our research can contribute to the standardization of rESWT treatment protocols, which can be widely applied in various clinical settings to treat musculoskeletal disorders.”

Source: “Quantitative assessment of acoustic field characteristics in water by radial extracorporeal shockwave therapy,” by Luyao He, Anyi Guo, Bo Wang, Qingquan Liu, Yajun Liu, and Xiaodong Chen, Physics of Fluids (2024). The a rticle can be accessed at https://doi.org/10.1063/5.0188052 .