Transcranial Pulse Stimulation (TPS) – What are shock waves?
From lithotripsy to versatile applications in orthopaedics, neurology and beyond
The history of medicine is rich in breakthroughs resulting from the transfer of principles from physics and technology. One such breakthrough is the application of shockwaves in medicine, a technology that has revolutionized the potential of non-invasive treatment since the early 1980s. Originally developed for the fragmentation of kidney stones, shockwave therapy has evolved into a versatile tool in the treatment of a wide range of medical disciplines. The history of the medical application of shockwaves begins with lithotripsy, a procedure that uses shockwave technology to eliminate kidney stones and gallstones without surgical intervention. This groundbreaking technique has allowed doctors to offer patients a far less painful and less invasive treatment option since 1982. Lithotripsy marked the beginning of a new era in stone treatment and laid the foundation for further research and development in the field of shockwave therapy. Over time, the range of applications for shock waves expanded far beyond urology. Extracorporeal shock wave therapy (ESWT) and radial shock wave therapy were developed to treat a variety of musculoskeletal conditions. With its ability to relieve pain and promote tissue healing, shockwave therapy has established itself as a valuable tool in orthopaedics and sports medicine.
Shockwaves in neurology, psychiatry and cardiology: transformative potential in therapy
One particularly exciting field is the extension of shockwave therapy to neurology and psychiatry. Here, scientists are conducting intensive research into how shock waves can be used to treat diseases such as Alzheimer’s dementia, other forms of dementia and Parkinson’s, as well as depression, attention deficit hyperactivity disorder (ADHD), autism and chronic fatigue syndrome (CES). This currently very dynamic research promises to open new doors for the treatment of conditions that were previously difficult to treat and underlines the transformative potential of shockwave therapy in areas beyond its original application. Transcranial Pulse Stimulation (TPS) is an innovative application of shockwave therapy that was developed specifically for the treatment of neurological and neuropsychiatric diseases and has been spreading internationally in clinics and practices since 2020. By using extremely low-energy, focused shock waves, TPS enables targeted stimulation of brain areas by supporting neuronal activity and regeneration without surgical intervention and helping to improve neuroplastic processes. Another advantage is its marginal side effect burden, if any. And there is another medical specialty: the broad spectrum of shockwave therapy is now also evident in cardiology, where it is used to promote blood circulation and regenerate heart tissue, thus opening up new possibilities in the treatment of heart disease.
The scientific basis of shock waves in medicine
Shock waves are high-energy, acoustic impulses that are characterized by their ability to propagate at high speed in different media – from liquids to solid bodies. In medical applications, they are generated by special devices that release energy in the form of sound waves. These waves are characterized by a very steep increase in pressure followed by an abrupt drop, which allows them to reach deep tissue layers in a targeted manner without damaging the overlying layers. The mode of action of shock waves in medicine is based on their unique physical properties: they induce mechanical stress and strain in the tissue, which leads to various biological reactions at the cellular level. These include the release of growth factors, the stimulation of angiogenesis, the improvement of blood circulation and the activation of stem cells. These processes contribute to the healing of tissue damage, relieve pain and support the restoration of function.
Customizing shockwave energy for specific medical applications
Shock waves are not only capable of exerting targeted forces in tissue areas close to the surface. Thanks to their high-frequency components in the megahertz range and the associated short pulse lengths of just a few millimetres, they can be precisely targeted at deeper areas of the body. In these deeper areas, the pulse transmission mechanism makes it possible to generate longer stimulation pulses that are in the range of physiologically relevant milliseconds and have a targeted effect there. The use of shock waves in medicine varies greatly depending on the treatment objective and the respective tissue type. Different energy flow densities enable precise and targeted therapy, from the dissolution of kidney stones to tissue regeneration. Extracorporeal shock wave lithotripsy (ESWL) uses high-energy shock waves to treat kidney stones. These generate a positive pressure pulse of up to 100 MPa (up to 1000 bar) and last up to 2 microseconds, followed by a negative pressure pulse of up to -10 MPa. With energies of over 3 mJ/mm2, they penetrate skin and muscles without causing damage and are specifically effective on solid objects such as stones. In orthopaedics, on the other hand, focused shock wave therapy (ESWT) is used, the energy of which is in the medium range up to 1 mJ/mm2. The aim is not to destroy, but to stimulate tissue and bone structures in order to promote healing processes through improved blood circulation and metabolism. The application is limited to specific target areas, which means that surrounding tissue remains largely unaffected. Transcranial Pulse Stimulation (TPS) for the treatment of neurodegenerative and neurophysiological diseases uses particularly low-energy shock waves of up to 0.25 mJ/mm2 . These low energies do not cause heating of the brain tissue, but have an activating and regenerating effect. The action potential of the shock waves supports the transmission of stimuli and promotes communication between neurons without damaging the surrounding tissue.
Mechanotransduction: the core principle of shock wave therapy
Mechanotransduction describes the process by which cells absorb mechanical stimuli from their environment and convert them into biochemical signals that trigger cellular responses. This process is fundamental to the mode of action of shock wave therapy, as the applied shock waves serve as mechanical stimuli that penetrate deep into the tissue. The induced mechanical stresses activate cells and stimulate biological processes that are essential for tissue repair and regeneration. Mechanotransduction leads to a cascade of cellular reactions: It increases the expression of growth factors, promotes angiogenesis and stimulates the proliferation as well as migration of cells. These effects contribute significantly to pain relief, the healing of inflamed or damaged tissue and the restoration of function. Mechanotransduction thus makes it possible to convert physical energy into therapeutic effects, making shockwave therapy a powerful tool in modern medicine.
Scientifically proven and investigated effects of shockwave therapy
The effects and mechanisms of shockwaves listed below have either been proven by scientific research or are currently the focus of current scientific evaluations: