Shockwave therapy – a term that continues to be used to encompass both focused shock wave and radial pressure wave therapies – can be used to stimulate the body’s natural healing process, with positive effects demonstrated on bone and tendon repair and tissue regeneration. But how does this work?
At our physio clinic bristol, both focused shock waves and radial pressure waves influence cellular activity through mechano-transduction, where the mechanical energy of an acoustic wave is converted into biochemical energy within the cell.
With focused shock wave (F-SW) therapy, this is primarily achieved through the effects of cavitation, whereas radial shockwave (R-SW) therapy uses pressure waves to cause cellular change.
What is Cavitation?
The negative pressure created by the wave generates gas-filled bubbles in water at room temperature, which are normally only seen in boiling water.
When these bubbles are concentrated in a small area, such as in F-SW therapy, they generate secondary pressure waves in a process known as “stable cavitation.” When the bubbles burst, they release energy at the focal point of the application. This “microtrauma” stimulates the body’s self-healing ability and leads to tissue regeneration.
While some cavitation also occurs during R-SW therapy, the level is only superficial, and not thought to be significant.
How Shockwave Therapy Aids Healing
F-SW and R-SW therapies are pro-inflammatory modalities which can be used to “reboot” the healing process in stalled, chronic conditions1.
How Shockwave Can Help Your Condition is closely linked to the body’s natural healing process, which occurs in four stages. First, the body responds to injury by bleeding, followed by inflammation. Within a few hours to days, the third stage begins, known as proliferation, where new tissue is created to rebuild the wound. Finally, after a few weeks, the remodelling stage starts, during which the wound fully closes.
Of all these stages of the healing cascade, the most important is inflammation. Without it, proliferation and remodelling will not take place. In chronic conditions, something has gone wrong during the later proliferation and remodelling stages of the normal healing process, preventing it from progressing. Like a computer with a serious error, this process needs to be rebooted for progress to be made by using the pro-inflammatory action of F-SW or R-SW therapy. That is why long-term injuries are so persistent.
Other Physiological Effects
Along with its influence on inflammation, shock wave therapy has been shown to have other physical effects on the body:
New blood vessel formation
Due to microtraumas caused by shock wave therapy, there is a significant increase in the expression of growth factors. These growth factors are involved in the process of neovascularization, where small blood vessels are stimulated to form and grow, which has a positive effect on improved blood supply, bone and tendon repair, and tissue regeneration.
Collagen production
Shock wave therapy stimulates procollagen synthesis, necessary for the repair of damaged musculoskeletal and ligament structures. It forces the newly created collagen fibres into a longitudinal structure, making the newly formed tendon fibres denser and stiffer, with a firmer structure.
Tenocyte proliferation
Shock wave therapy leads to an increase in transforming growth factor, which is known to regulate tendon repair.
Fibrotic tissue and scar remodelling
Shock wave therapy alters the expression of fibrosis-related molecules in fibroblasts, which affects scar remodelling and resorption.
Analgesia
RSW therapy has a confirmed effect in improving the symptoms of pain.
Reducing hypertonia in spastic muscles
Both F-SW and RPW have been proven effective here, with RSW particularly effective in aiding increased range of movement.
I have found the use of shockwave for tissue injury has transformed my practice.
