In this blog post, we’ll explore this new technology that is making waves (no pun intended) in the world of manual therapy & sports medicine. Shockwave therapy is a form of mechanotherapy and has nothing to do with electrical shocks.
Extracorporeal Shockwave Therapy is an evidence-based, non-surgical and highly effective technology for treating tendonitis, tendinosis, tendinopathies and other chronic musculoskeletal conditions.
Introduction
Extracorporeal Shockwave Therapy, or ESWT, has been around for some time. The word “extracorporeal” translated means “situated or occurring outside of the body”. It is not a description of the type of shockwave produced. It simply means that a shockwave is produced outside of the body.
What is a Shockwave?
Shockwaves are short, intense pressure waves that travel faster than the speed of sound. Shockwaves are different from other kinds of energy wave (electromagnetic, acoustic, light etc.) because they cause deformation the tissue that they move through. A rapid spike in pressure causes compression of the tissue that the shockwaves passes through. This is followed by a tensile phase where there is negative pressure within the tissue.
Shockwaves occur all around us. Think about that feeling you get in your chest when there’s an explosion, a big lightning strike or when an aeroplane breaks the sound barrier.
Graph demonstrating the relationship between pressure and time of a shockwave
History of shockwave therapy in medicine
The interactions between shockwaves and biological tissues have been studied since 1968. In 1971 researchers used shockwaves to disintegrate kidney stones. Today it is known as Shockwave lithotripsy and is the first choice for treating kidney and ureteral stones (ISMST).
In the 1980s, the interaction of shockwaves on bone was studied so that researchers could determine if the hips were at risk when performing lithotripsy on kidney stones. No negative effects were noted in intact bones. They found that shockwaves could increase bone production and was later used to treat non-union fractures.
In the 1990s the first reports on orthopaedic conditions such as calcific tendinopathy, heel spurs and epicondylitis were published.
You can read more about the history of shockwave therapy by following this link to the International Society for Medical Shockwave Treatment website.
First generation shockwave lithotripsy machine
How does shockwave therapy work?
An air compressor accelerates a projectile inside the applicator head at high velocity. The projectile strikes an elastically suspended impact transmitter that is in direct contact with a person’s skin directly above the structure that needs to be treated. The kinetic energy of the projectile is converted into an acoustic pressure wave on impact which travels through tissue as an ultrasonic pulse or shockwave.
The physical energy from a shockwave causes mechanical distortion of cells of the tissue being treated, resulting in a biochemical response. This process is called mechanotransduction.
Exercise rehabilitation and shockwave therapy are both forms of mechanotransduction.
What effects does shockwave therapy have on the body?
Many different chemical mediators are released by the cells exposed to shockwaves and are responsible for the therapeutic effects listed below.
Improved blood supply
Blood supply is improved due to the formation of new blood vessels within the tendon and bone (neovascularization). This is due to the release of a substance called Nitric Oxide (NO).
Pain relief
A neurotransmitter in our bodies called “Substance P” is responsible for relaying pain signals to the nervous system. Pain relief after treatment occurs due to decreased local concentration of Substance P in the tissue.
Pro-inflammatory action
By positively regulating inflammation it restarts the healing process in chronic, degenerative conditions that are in a failed state of healing.
Tendon regeneration
There is increased collagen synthesis and proliferation of tenocytes (the cells responsible for repairing and maintaining healthy tendons).
Regeneration of bone
This is due to the formation of new blood vessels and the increased activity of osteoblasts (the cells responsible for forming new bone)
The effects of shockwave therapy on Tendons
Quite possibly the number one reason sports chiropractors, physiotherapists and other sports medicine professionals use shockwave therapy in their clinics is for the effect that it has on tendons. Tendon pathophysiology is complicated so I’ll simplify it as best I can.
Adaption of the tendon continuum (Cook & Purdam 2009)
Let’s use an example of a novice runner who comes in with Achilles tendinopathy. This person usually runs 5km per week but then drastically increases their running distance and ends up running 40km in a week. Excessive load on the tendon has caused the patient to progress along the red arrow. Their previously normal Achilles tendon has now become a “reactive tendinopathy”. If they were to modify their training load and rehabilitate their Achilles they would progress along the green arrow until their tendon returned to a normal state. But if they continue to overload their Achilles tendon it’ll degenerate further and land up in a state of “tendon disrepair”. If not managed properly from here the tendon can degenerate further and will eventually become a “degenerative tendinopathy”. With the appropriate load, the patient’s tendon will progress along the green line back towards a normal tendon.
Sounds simple right? Well, pain tends to complicate matters. Some painful tendons can appear normal on ultrasound scans. Studies have found that there is sometimes a disproportionate amount of pain in relation to the severity of tendon damage.
Why is shockwave so beneficial as part of a tendon rehabilitation program?
As mentioned earlier, shockwave therapy causes new blood vessel formation in tendons, increases tenocyte activity and collagen synthesis. It can drastically decrease pain by decreasing local concentration of Substance P. This gives patients the ability to perform their rehabilitation exercises with less pain 48-hours after their shockwave session. We know that tendons respond positively to rehabilitation exercises which helps them progress along that green arrow towards becoming a normal tendon again. The combination of shockwave and exercise rehabilitation has been shown to have the best clinical outcomes.
What conditions can be treated with shockwave therapy?
Some of the most common orthopaedic conditions that respond well to shockwave therapy include:
Shockwave therapy being used to treat plantar fasciitis
When should shockwave therapy be avoided?
There are several instances when shockwave therapy should be avoided:
Does shockwave therapy hurt?
There will be mild discomfort during the procedure. To get the best results, we need to deliver as much energy as you can tolerate without exceeding a self-rated 7/10 on the pain scale.
Is shockwave therapy safe?
Shockwave therapy is considered to be a safe and non-invasive therapy. However, some minor side effects that have been reported include:
How many sessions will I need?
An optimum shockwave treatment protocol is 1 session per week for 3 weeks. Randomised clinical trials have found there to be an 89% success rate when following these guidelines.
How much does shockwave therapy cost?
There is an additional cost for shockwave therapy over and above our regular consultation rates. Click here to go to our online booking page to see what our rates are.
Before treatment
A thorough assessment & clinical diagnosis needs to be established before beginning treatment. This will be performed during your initial consultation and treatment can be performed the same day if indicated. You may need to be referred to your GP for further scans or blood tests before starting treatment. All this will be discussed with you during your appointment.
Conclusion
Shockwave therapy is the gold standard treatment for a variety of chronic musculoskeletal and tendon pathologies. If it ends with “itis”, “otis” or “opathy”, there’s a good chance it’ll respond well to shockwave therapy. It is extremely safe with little to no side effects and in many cases can be an alternative to surgery.
If you’re looking for shockwave therapy in Brisbane, click here to book your session online.
About the author:
Dr Michael Benporath is a chiropractor with a postgraduate International Certificate in Sports Chiropractic. He practices at Prime Health Co. in Newmarket, Brisbane Northside.
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References
Wang, F. Yang, K. Chen, R. et al. (2002). Extracorporeal shock wave promotes growth and differentiation of bone marrow stromal cells towards osteoprogenitors associated with induction of TGF – B1. Journal bone joint surgery 84:457 – 461
The International Society for Medical Shockwave Treatment (ISMST). https://www.shockwavetherapy.org
