A Deeper Look into StemWave^® by Dr. Allen Manison, DC, DACBSP, CSCS, CCEP

StemWave^® delivers focused waves through a high energy electrical discharge in water. The voltage is discharged between the opposing tips (plus and minus pole) of an electrode. The spark creates an equalization of voltage between the two tips of the electrode and then a plasma bubble is created. This bubble then explodes, compressing the water around it, and generates a pressure >10 MPa within only a few nanoseconds. Specifically with Modus-F, the initial pulse wave produces an 11.3 MPa spike at its highest level, and the tensile wave is -2.7 MPa. This pulse wave form eclipses the range of other electrohydraulic ESWT devices (for comparisons, the other forms of pulse wave are electromagnetic and piezoelectric).

A true pulse wave (focused electrohydraulic ESWT, the same type of wave created by Modus-F), has 3 distinct components:
1. Acoustic pulses with high positive pressure (up to 100MPa)
2. Fast and steep rise time
3. Comparatively small negative pressure (tensile wave)

The pulse wave energy is then delivered through a focused applicator head in the form of a pulse wave/pressure wave. The applicator head, instead of being more parabolic in nature as is the case with unfocused ESWT, is angled to focus the pulse wave to a smaller area of tissue. This allows for better penetration as the size of the impedance zone is decreased when applying similar amounts of intensity. Even after the energy hits the terminal point as directed by the applicator head, the pulse waves can continue and treat to a deeper penetration level. This allows for energy distribution that is able to be used for deeper penetration to aid in healing. Despite the speed of the pulse wave, it does NOT create any micro trauma. As a comparison of focused pulse waves to other forms of sound therapies, ultrasound does not create pulse waves, but rather periodic oscillations with no peak pressure or fast rise/drop times. Radial pulse waves have a low steeping effect and slow rise time: they are not true pulse waves. Even electromagnetic focused pulse waves have been shown to not meet the true definition of pulse waves. Please note that all forms of ESWT have been shown in the literature to have merit, depending on the application. It is not my intent to discredit other forms of acoustic therapies, but rather to share the differences provided by using focused electrohydraulic forms of pulse wave, such as the ones produced by Modus-F. The mechanical input delivered by the pulse wave is registered in our tissues, and the body adapts in a biological/chemical way. This is called Mechanotransduction. Simply put, the mechanical stimulation from the pulse waves creates biochemical changes in the target tissue. There are many biochemical changes that occur, but the main ones of interest are up regulation of immune function, as well as recruitment of mesenchymal stem cells through Toll Like Receptor 3 (TLR3) identification of mRNA release from the cell following the administration of true pulse waves.

Clinical Application

ESWT makes for a very valuable treatment option for the chiropractor. It adds another means to address soft and hard tissue pathologies that may not respond to other interventions. ESWT has been studied and shown to help with many health conditions, such as: Peripheral nerve regeneration, diabetic neuropathy, reduction of inflammation to aid heart tissue regeneration, coccydynia, stress fractures in athletes, stem cell activation, cell proliferation and wound healing, a viable option to avoid surgery for certain musculoskeletal disorders, progressive systemic sclerosis, knee osteoarthritis, erectile dysfunction, chronic pelvic pain, spinal pathology, non-unions, early adult osteochondritis dissecans, and more. In regard to specific musculoskeletal conditions, a meta-analysis study showed that ESWT is more successful than ultrasound for lateral epicondylitis, and there’s enough data to validate its use for a plethora of tendinopathies. ESWT was shown in 2019 to be a more successful treatment approach for plantar fasciitis than methyl prednisone injections, and a network meta-analysis determined that ESWT was the best intervention when compared to 7 other interventions for plantar fasciitis. It was even shown to be as effective as foot orthotics. ESWT has been shown to be a beneficial intervention when treating tough conditions like Achilles tendinopathy, along with insertional Achilles tendinopathy, with and without Haglund’s deformity. ESWT has been shown to have positive effects with lateral epicondylitis and provide for grip strength improvement for a greater period when compared with physical therapy and corticosteroid injections. The data and studies show that ESWT is an effective modality for treating most musculoskeletal conditions, namely those that would be seen in a chiropractic or physical therapy setting.

Effects on the Body

When we have an injury, be it a macro (big) trauma, or micro (small) trauma, our tissues have to be able to communicate with the rest of our body to inform it of the harm. This is done by damaged cells releasing different constituents, such as chromatin (affects DNA health), proteins, and RNA (it forms stable double helix RNA when released in this fashion). In some spaces, it is also called cytoplasmic/cytosolic, or even messenger RNA. Researchers have given a name to the group of released chemicals and that is Damage/Danger Associated Molecular Patterns (DAMPs). DAMPs create inflammatory processes and can even play a role in disease formation due to the inflammation they create. What is interesting about this grouping of chemicals is that it is currently believed that RNA is responsible for the heavy recruitment of the healing agents (this is discussed below with research to validate this point). The body responds to injury by activating the innate immune system along with bringing in stem cells (to rebuild damaged tissues) due to a response from a certain type of receptors, called toll-like receptors (TLR). The most involved and studied are the TLR2, TLR 3, TLR4, and TLR5. The human body is understood to have 10 TLRs, but there is a bit of a debate to this. The ones that most apply to our discussion about reduction of inflammation and regeneration are the TLR3 and TL4. In regard to tissue healing and regeneration, we have two primary Toll Like Receptors that aid in the process. The problem is that one of these (TLR4) actually is responsible for too much initial inflammation and that can be harmful. Although TLR3 has been shown to have an initial inflammatory response, it is known to be short and TLR3 is responsible for immediate immune response to reduce inflammation/pain and recruit stem cells to the region to aid in healing. As previously mentioned, TLR4 can be useful as it brings about inflammation to help with fighting off bacterial infection, but it tends to create a lot of issues by bringing about excessive inflammation that can exacerbate or create its own problems. We may want to consider this the case with over-swelling of an ankle injury that leads to compartment syndrome, too much swelling in the brain after a head injury, and similar issues. Studies show that TLR4 can create vasospasm, neurodegeneration, CNS inflammation, and a host of other bad effects. It’s deleterious effects on neuroimmune and neuroendocrine function can be quite scary. Ideally, we want more of a TLR3 effect vs. a TLR4 one.

TLR3 ultimately brings about a cell protective effect. It is also responsible for angiogenesis (new blood vessels). This is a result of the Mechanotransduction, previously discussed, whereby the pulse wave (mechanical input) creates a biological response to create new vessels (biochemical effect). The entire mechanism of how this occurs is still not entirely understood, but it is known to occur. TLR3 also triggers what we’d consider to be a more proper immune response and aids in delivering stem cells to help regenerate. Although TLR3 is known to trigger an early inflammatory response, it has a potent anti-inflammatory effect following. We should keep this in mind when we are administering pulse waves as too many and too much intensity might actually not work in the patient’s favor. We know that TLR3 and TLR4 communicate. Ideally, the communication between the two helps to bring out the best innate treatment effects. However, this is not always the case. So, where does ESWT come into play with all of this? What if I were to tell you that ESWT has been shown to not only help bone and tendons heal, but also increase blood flow in muscles? Can ESWT help prevent arthritis? Can it help with damaged cartilage, bone disease, motor function, can it regenerate muscles, and more? How about aiding organ tissue? Well, there are studies that show it does just about all of this. It does so through the aforementioned Mechanotransduction. The biochemical response that the body has to the unique ESWT.

Let’s now apply that mechanical stimulation creating the biochemical effects we read about earlier (Mechanotransduction). We learned above that those injured cells leak certain constituents, leading to the TLR response. Physically, pulse waves (moving at over 3300 mph) essentially compress, then stretch the cell; and although they do NOT create damage of any kind or create heat, they trick the cell into thinking something is wrong. This pulse wave effect stimulates the cells to release those same constituents that damaged cells leak, and as you can probably guess, the TLR respond. It is important to note that TLR3 is not tricked by just any compound coming out of a cell: TLR3 is only triggered by RNA. This is where pulse wave therapy gets even more interesting. Not only do the pulse waves imitate an injury scenario without actually creating any injury, but the pulse waves are effective at downregulating (reducing) the effects of TLR4 (the TLR that tends to create too much inflammation), while enhancing the effects of TLR3 (initial inflammation followed by an anti inflammatory effect). These studies have shown that ESWT can help bodies heal and regenerate.

Safety Issues

Regarding safety, I quote the Dedes et. al. study Effectiveness and Safety of Pulse Wave Therapy in Tendinopathies, in Mater Sociomed, 2018 “From the results of the present study, extracorporeal pulse wave therapy is an effective modality in relieving pain intensity and increase the functionality and quality of life in various tendinopathies such as plantar fasciitis, elbow tendinopathy, Achilles tendinopathy and rotator cuff tendinopathy. It can be done on an out-patient basis with no patient restrictions and there are no significant side effects. Extracorporeal pulse wave therapy as utilized in the current study seems to be a safe and effective treatment in all tendinopathies examined. Thus, patients who failed to respond to conventional treatment for any of the above tendinopathies can use pulse wave therapy as an alternative method, which can significantly improve pain, functionality and quality of life.” The studies show that ESWT is used with more than just tendinopathies, and the data are clear that it is very safe and offers excellent results.

Conclusion

I hope the information provided here answered your question and helps give you a strong background understanding of what the Modus-F is, how it functions, and what it can do for your patients. Its ability to immediately reduce pain/inflammation and recruit stem cells is truly unique. Pulse wave therapy is an interesting topic in the world of rehabilitative and regenerative medicine at this time. A great general resource for further information, if you are interested, is the International Society of Medical Pulse wave Treatment.