What is PEMF?
PEMF is energy that heals and as such it is energy medicine. PEMF is Natural and all around us in the Earth's Geomagnetic fields and Schumann resonances. PEMFs connect us all on planet earth, and we even emit PEMFs which can be measured with a sensitive magnetometer.
PEMF stands for Pulsed ElectroMagnetic Fields and PEMFs are - ideally - pure magnetic fields that change with time, or sometimes called time varying magnetic fields.
PEMF is energy that heals and as such it is energy medicine. PEMF is Natural and all around us in the Earth's Geomagnetic fields and Schumann resonances. PEMFs connect us all on planet earth, and we even emit PEMFs which can be measured with a sensitive magnetometer.
PEMF stands for Pulsed ElectroMagnetic Fields and PEMFs are - ideally - pure magnetic fields that change with time, or sometimes called time varying magnetic fields.
Ampere's Law
Did you know you can use current loops (solenoids) to create an identical magnetic field that a magnet gives us?
Ampère’s law was devised to quantify an accidental discovery made in 1820 by Hans Christian Ørsted in 1820. While giving a physics demonstration at the University of Copenhagen, Ørsted noticed that electric currents flowing from a battery and through a wire caused nearby compass needles to wiggle when the battery was switched on and off. The momentous conclusion was that electric currents can create magnetic fields in the surrounding space. In other words, electricity gives rise to magnetism.
Did you know you can use current loops (solenoids) to create an identical magnetic field that a magnet gives us?
Ampère’s law was devised to quantify an accidental discovery made in 1820 by Hans Christian Ørsted in 1820. While giving a physics demonstration at the University of Copenhagen, Ørsted noticed that electric currents flowing from a battery and through a wire caused nearby compass needles to wiggle when the battery was switched on and off. The momentous conclusion was that electric currents can create magnetic fields in the surrounding space. In other words, electricity gives rise to magnetism.
What Oersted Found...
Whereas stationary charges produce an electric field, moving charges in addition produce a magnetic field. In fact magnetic fields are easier to detect, all you need is a boy scout compass. Now if you hold a tiny compass in the vicinity of a current carrying wire, you quickly discover a peculiar thing:
The field does not point toward the wire nor away from it, but rather it circles around the wire. In fact if you grab the wire with your right hand - thumb in the direction of current - your fingers curl around in the direction of the magnetic field (Right Hand Rule).
Whereas stationary charges produce an electric field, moving charges in addition produce a magnetic field. In fact magnetic fields are easier to detect, all you need is a boy scout compass. Now if you hold a tiny compass in the vicinity of a current carrying wire, you quickly discover a peculiar thing:
The field does not point toward the wire nor away from it, but rather it circles around the wire. In fact if you grab the wire with your right hand - thumb in the direction of current - your fingers curl around in the direction of the magnetic field (Right Hand Rule).
Magnetism, at its root, arises from CURRENT LOOPS!
Microscopic current loops, Spin magnetic moments of elementary particles --> Gives rise to magnetic materials.
The magnetic properties of materials are mainly due to the magnetic moments of their atoms' orbiting electrons (little electrons orbiting nucleus (current LOOPS) all aligned in bar magnets!).
2) Macroscopic Current Loops - Electric currents in wires and current loops (dipoles). Earth's current is in essence a gigantic current loop (dynamo theory of earth's magnetic field).
Microscopic current loops, Spin magnetic moments of elementary particles --> Gives rise to magnetic materials.
The magnetic properties of materials are mainly due to the magnetic moments of their atoms' orbiting electrons (little electrons orbiting nucleus (current LOOPS) all aligned in bar magnets!).
2) Macroscopic Current Loops - Electric currents in wires and current loops (dipoles). Earth's current is in essence a gigantic current loop (dynamo theory of earth's magnetic field).
That is, we can use electricity to create magnetism like a magnetic field around a magnet using with a loop of current. But unlike a static magnet, we can vary the current in all kinds of ways with different waveforms, frequencies and intensities while static magnets ONLY vary in size and intensity.
Most of us are familiar with magnetic fields like refrigerator magnets, horseshoe magnets, and visualizing magnetic fields with Iron filings, and PEMFs are similar but instead of a constant magnetic field, you have a magnetic field that is vibrating. Image a static bubble vs a vibrating bubble. And because PEMF is a vibrating or changing magnetic field, it can work in ways that static magnets cannot.
Most of us are familiar with magnetic fields like refrigerator magnets, horseshoe magnets, and visualizing magnetic fields with Iron filings, and PEMFs are similar but instead of a constant magnetic field, you have a magnetic field that is vibrating. Image a static bubble vs a vibrating bubble. And because PEMF is a vibrating or changing magnetic field, it can work in ways that static magnets cannot.
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How does it work? The Physics of PEMF
Uses Faradays Law AND Magnetic Resonance to Wirelessly energize all your cells and improve microcirculation and healing currents - Kinetic and Potential.
Faradays
1) Faraday's Law - You want a rapid rise and fall signal like a squarewave or sawtooth. This induces microcurrents and creates ion transport deep within the tissues. PEMF is literally 3D microcurrent therapy because of Faraday's Law and penetrates deeper and works better than TENS, Estim, FSM etc.
Faraday's Law is
Uses Faradays Law AND Magnetic Resonance to Wirelessly energize all your cells and improve microcirculation and healing currents - Kinetic and Potential.
Faradays
1) Faraday's Law - You want a rapid rise and fall signal like a squarewave or sawtooth. This induces microcurrents and creates ion transport deep within the tissues. PEMF is literally 3D microcurrent therapy because of Faraday's Law and penetrates deeper and works better than TENS, Estim, FSM etc.
Faraday's Law is
EMF = -dΦ/dt
Φ is the FLUX and is equal to the Intensity of the Field TIMES the AREA!!
You have to incorporate the size and Geometry of the Coil to Get the Right Answer!!
EMF is the electromotive force in Volts which is the drive force for ion transport in the body. Φ= L*I which means it depends on BOTH the intensity AND the geometry or SIZE of the coil!
Φ is the FLUX and is equal to the Intensity of the Field TIMES the AREA!!
You have to incorporate the size and Geometry of the Coil to Get the Right Answer!!
EMF is the electromotive force in Volts which is the drive force for ion transport in the body. Φ= L*I which means it depends on BOTH the intensity AND the geometry or SIZE of the coil!
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Slew Rate - dB/dt
Slew rate is defined as the change in magnetic field intensity (dB) divided by the change in time (dT) - rise/run, where dB/dT is the slope. A high slew rate will appear on an oscilloscope as steep slope.
Faraday's law dictates that a higher slew rate will induce more EMF or voltage which in turns induces more current flow in a conductor (like a copper wire or the highly conductive human body).
Slew rate, or the speed at which the magnetic field intensity changes, is believed to influence the efficacy of pulsed electromagnetic field (PEMF) therapy.
30 T/s
30 mT / 900 uS
3 mT / 100 us
3 uT/ 100ns (Assisi)
Slew rate is defined as the change in magnetic field intensity (dB) divided by the change in time (dT) - rise/run, where dB/dT is the slope. A high slew rate will appear on an oscilloscope as steep slope.
Faraday's law dictates that a higher slew rate will induce more EMF or voltage which in turns induces more current flow in a conductor (like a copper wire or the highly conductive human body).
Slew rate, or the speed at which the magnetic field intensity changes, is believed to influence the efficacy of pulsed electromagnetic field (PEMF) therapy.
30 T/s
30 mT / 900 uS
3 mT / 100 us
3 uT/ 100ns (Assisi)
Mechanism of Slew Rate - Faraday Induction or Inductive Coupling
There had also been some good scientific evidence in support of the Faraday Induction mechanism of PEMF (the theory that emphasizes dB/dt and trapezoidal waveforms) since 1968, but it had been lost in the noise surrounding PEMF technologies. Since then the electro-magnetic induction-based theory of PEMF was very strongly supported by research like the NASA-JSC and DARPA in the mid 1990’s and early 2000’s by Goodwin and Dennis.
PEMF technology based on Slew rate does not require the assumption that magnetic fields themselves interact directly with living tissues by means of some form of magic, or a complex and poorly-understood quantum physical effect.
Through the well- understood physical mechanism of electro-magnetic induction, wherein the external pulse generator uses non-invasive electric coils to create time-varying magnetic pulses that penetrate living tissue essentially without any strong direct interactions because the living tissue is essentially “transparent” to the magnetic fields themselves. These pulses are inductively coupled across space to the structures within living tissues that have conductive paths, for example around the cell membrane in the paracellular space, or around organelles within cells. These conductive paths within the tissue act as the “secondary” coil of what can essentially be viewed as an air-core electrical transformer, the primary coil being the external PEMF coil.
Based on the well-understood Law of Induction, one of the four classical Maxwell Equations, electrical currents are induced in and around the cells within the living tissue within the conductive paths in and around cells. This takes the form of ions in solution being forced to move, driven by the induced fields [1] .
There had also been some good scientific evidence in support of the Faraday Induction mechanism of PEMF (the theory that emphasizes dB/dt and trapezoidal waveforms) since 1968, but it had been lost in the noise surrounding PEMF technologies. Since then the electro-magnetic induction-based theory of PEMF was very strongly supported by research like the NASA-JSC and DARPA in the mid 1990’s and early 2000’s by Goodwin and Dennis.
PEMF technology based on Slew rate does not require the assumption that magnetic fields themselves interact directly with living tissues by means of some form of magic, or a complex and poorly-understood quantum physical effect.
Through the well- understood physical mechanism of electro-magnetic induction, wherein the external pulse generator uses non-invasive electric coils to create time-varying magnetic pulses that penetrate living tissue essentially without any strong direct interactions because the living tissue is essentially “transparent” to the magnetic fields themselves. These pulses are inductively coupled across space to the structures within living tissues that have conductive paths, for example around the cell membrane in the paracellular space, or around organelles within cells. These conductive paths within the tissue act as the “secondary” coil of what can essentially be viewed as an air-core electrical transformer, the primary coil being the external PEMF coil.
Based on the well-understood Law of Induction, one of the four classical Maxwell Equations, electrical currents are induced in and around the cells within the living tissue within the conductive paths in and around cells. This takes the form of ions in solution being forced to move, driven by the induced fields [1] .
Beginnings
**Bone - Currents of Injury and Currents of Healing*
A Ray of Hope in Ancient Rome
Electricity is one of the most significant forces of nature and has had a long history of involve- ment in biomedicine. As early as 46 ce, the Roman physician Scribonium Largus used electric rays, genus Torpedo, to cure the pain of gout and headaches. For headache, the live ray was placed against the painful spot. For gout, the patient’s feet are placed on a live black Torpedo while standing on the moist shore washed by the sea. From what we now know about electrons and inflammation, this treatment may not be as surprising as it seems
Frog Legs and Frankenstein
It was not until the late sixteenth century that a true science of bioelectricity was born, suddenly, with an electric spark. This was the discovery of ‘animal electricity’ by Luigi Galvani, a physician and surgeon in Bologna, Italy. Galvani (it may actually have been his wife, Lucia, who saw it first) noticed that recently dissected frog legs twitched vigorously when a nearby electric generator emitted a spark. The phenomenon was so interesting that Galvani made a career of studying the twitches and how, for example, an ‘electric fluid’ in a nerve could be conducted via a metallic wire to a muscle, which would contract.
**Bone - Currents of Injury and Currents of Healing*
A Ray of Hope in Ancient Rome
Electricity is one of the most significant forces of nature and has had a long history of involve- ment in biomedicine. As early as 46 ce, the Roman physician Scribonium Largus used electric rays, genus Torpedo, to cure the pain of gout and headaches. For headache, the live ray was placed against the painful spot. For gout, the patient’s feet are placed on a live black Torpedo while standing on the moist shore washed by the sea. From what we now know about electrons and inflammation, this treatment may not be as surprising as it seems
Frog Legs and Frankenstein
It was not until the late sixteenth century that a true science of bioelectricity was born, suddenly, with an electric spark. This was the discovery of ‘animal electricity’ by Luigi Galvani, a physician and surgeon in Bologna, Italy. Galvani (it may actually have been his wife, Lucia, who saw it first) noticed that recently dissected frog legs twitched vigorously when a nearby electric generator emitted a spark. The phenomenon was so interesting that Galvani made a career of studying the twitches and how, for example, an ‘electric fluid’ in a nerve could be conducted via a metallic wire to a muscle, which would contract.
Brief Overview
Lesion Currents
The employment of physical energy to modulate osteogenetic response and, ultimately, to enhance fracture healing is a topic widely researched in Europe. Interest in the relationship between biological systems and electrical energy can be dated back as far as the studies by Galvani1 and Matteucci (1811– 1868) who, already in the nineteenth century, had identified the lesion currents and had perceived their role in repair processes [1].
In the last century, the studies performed by Fukada and Yasuda [2] and by Bassett and Becker [3] identified the relationship between mechanical loading and electrical activity in the bone, wherein lie the scientific origins of the electrical, magnetic, and mechanical stimulation of osteogenesis.
Following the discovery of piezoelectricity in bone by the Japanese surgeon/ physicist team of Yasuda and Fukada, it became evident, for reasons still unclear, that small currents in the order of fractions of a milliampere, when applied to such discontinuities, are able to initiate the required bone growth process. Bassett subsequently explored the use of pulsed electromagnetic fields (PEMF) to deal with this condition [4] obtaining a success rate of about 80%, and FDA approval, and at the same time demonstrating that this medical condition could be dealt with in a noninvasive manner.
[1] Galvani L. De viribus electricitatis in motu musculari commen- tarius. Bologna: Ex typographia Instituti Scientiarum; 1791.
[2] Fukada E, Yasuda I. On the piezoelectric effect of bone.
J Phys Soc Japan 1957;12:121–8.
[3] Bassett CA, Becker RO. Generation of electric poten-
tials in bone in response to mechanical stress. Science
1962;137:1063–4.
[4] Basset CAL, Pawluk RJ, Pilla AA. Augmentation of bone
repair by inductively coupled magnetic field. Science
1974;184:575–9.
Lesion Currents
The employment of physical energy to modulate osteogenetic response and, ultimately, to enhance fracture healing is a topic widely researched in Europe. Interest in the relationship between biological systems and electrical energy can be dated back as far as the studies by Galvani1 and Matteucci (1811– 1868) who, already in the nineteenth century, had identified the lesion currents and had perceived their role in repair processes [1].
In the last century, the studies performed by Fukada and Yasuda [2] and by Bassett and Becker [3] identified the relationship between mechanical loading and electrical activity in the bone, wherein lie the scientific origins of the electrical, magnetic, and mechanical stimulation of osteogenesis.
Following the discovery of piezoelectricity in bone by the Japanese surgeon/ physicist team of Yasuda and Fukada, it became evident, for reasons still unclear, that small currents in the order of fractions of a milliampere, when applied to such discontinuities, are able to initiate the required bone growth process. Bassett subsequently explored the use of pulsed electromagnetic fields (PEMF) to deal with this condition [4] obtaining a success rate of about 80%, and FDA approval, and at the same time demonstrating that this medical condition could be dealt with in a noninvasive manner.
[1] Galvani L. De viribus electricitatis in motu musculari commen- tarius. Bologna: Ex typographia Instituti Scientiarum; 1791.
[2] Fukada E, Yasuda I. On the piezoelectric effect of bone.
J Phys Soc Japan 1957;12:121–8.
[3] Bassett CA, Becker RO. Generation of electric poten-
tials in bone in response to mechanical stress. Science
1962;137:1063–4.
[4] Basset CAL, Pawluk RJ, Pilla AA. Augmentation of bone
repair by inductively coupled magnetic field. Science
1974;184:575–9.
Injury Potential first discovered by Carlo Matteceuci 1844
The injury potential, also called the demarcation potential, is the difference in electrical potential between the injured and uninjured parts of a nerve, muscle, skin, or other tissue. It is an energetic phenomenon with important roles in wound healing – the intricate process in which the skin or another tissue or organ repairs itself after injury (Huttenlocher and Horwitz, 2007; Nguyen et al., 2009; Zaho et al., 2006).
The injured tissue has a negative voltage compared to the central part of the body.[3] The current of injury – also known as the demarcation current, hermann's demarcation current[1] or injury potential[2] – is the electric current from the central part of the body to an injured nerve or muscle, or to another injured excitable tissue.
In the early nineteenth century, Carlos Matteucci discovered what was later referred to as “currents of injury,” wherein he found that injured tissues created an electrical current that disappeared with the healing process. More than a 100 years later, Robert O. Becker followed up on these experiments, discovering that one could mimic nature by application of external electrical applications, specifically obtaining regrowth of amputated tissues by means of applied electric fields.8
Becker RO. The bioelectric factors in amphibian-limb regeneration. J Bone Joint Surg 1961;43:643–56.
Research has shown that artificial enhancement of the injury potential increases the rate of wound closure and the extent of regeneration. This means that a wide range of energy therapies, ranging from medical devices to hands-on treatments to acupuncture, can facilitate the healing of chronic wounds.
When the body’s endogenous bioelectric system does not produce normal wound repair, therapeutic electrical currents may be delivered into the ‘repair field’ from an external source. The applied current may serve to mimic the failed natural bioelectric currents, thereby promoting wound healing.
It has been found by Elmer J. Lund that establishing an artificial electrical field causing a current mimicking the current of injury could facilitate regeneration.[5] This potential for a regeneration therapy was further studied by Robert O. Becker, who described this work in his book The Body Electric. He found that the current of injury runs through the perineurium – through the myelin sheaths of the peripheral nerves.[3]
[3] Becker, R. O. (1961). "Search for Evidence of Axial Current Flow in Peripheral Nerves of Salamander". Science. 134 (3472): 101–2.
[5] H. Richard Leuchtag. "Voltage-Sensitive Ion Channels: Biophysics of Molecular Excitability". Retrieved 2012-08-01.
The injury potential, also called the demarcation potential, is the difference in electrical potential between the injured and uninjured parts of a nerve, muscle, skin, or other tissue. It is an energetic phenomenon with important roles in wound healing – the intricate process in which the skin or another tissue or organ repairs itself after injury (Huttenlocher and Horwitz, 2007; Nguyen et al., 2009; Zaho et al., 2006).
The injured tissue has a negative voltage compared to the central part of the body.[3] The current of injury – also known as the demarcation current, hermann's demarcation current[1] or injury potential[2] – is the electric current from the central part of the body to an injured nerve or muscle, or to another injured excitable tissue.
In the early nineteenth century, Carlos Matteucci discovered what was later referred to as “currents of injury,” wherein he found that injured tissues created an electrical current that disappeared with the healing process. More than a 100 years later, Robert O. Becker followed up on these experiments, discovering that one could mimic nature by application of external electrical applications, specifically obtaining regrowth of amputated tissues by means of applied electric fields.8
Becker RO. The bioelectric factors in amphibian-limb regeneration. J Bone Joint Surg 1961;43:643–56.
Research has shown that artificial enhancement of the injury potential increases the rate of wound closure and the extent of regeneration. This means that a wide range of energy therapies, ranging from medical devices to hands-on treatments to acupuncture, can facilitate the healing of chronic wounds.
When the body’s endogenous bioelectric system does not produce normal wound repair, therapeutic electrical currents may be delivered into the ‘repair field’ from an external source. The applied current may serve to mimic the failed natural bioelectric currents, thereby promoting wound healing.
It has been found by Elmer J. Lund that establishing an artificial electrical field causing a current mimicking the current of injury could facilitate regeneration.[5] This potential for a regeneration therapy was further studied by Robert O. Becker, who described this work in his book The Body Electric. He found that the current of injury runs through the perineurium – through the myelin sheaths of the peripheral nerves.[3]
[3] Becker, R. O. (1961). "Search for Evidence of Axial Current Flow in Peripheral Nerves of Salamander". Science. 134 (3472): 101–2.
[5] H. Richard Leuchtag. "Voltage-Sensitive Ion Channels: Biophysics of Molecular Excitability". Retrieved 2012-08-01.
Dr John Birch - 150 years ahead of his Time - Healing Nonunions with Electricity
It did not take very long for Galvani’s discoveries to be applied in medicine. One early discovery that has endured to this day is the use of electricity to stimulate the healing of bone fractures that have failed to heal. In 1812, Dr. John Birch in London healed a nonunion of the tibia with electric currents passed through needles surgically implanted in the fracture region. By the mid-1800s, this had become the preferred method for treating slow-healing bone fractures. A modern version of this treatment, widely preferred and used by orthopedic surgeons, is an implantable electrical stimulation device (Figure 5.7).
Medical electricity had its golden era between the late 1700s and the early 1900s. During that period, a variety of electrical healing devices were developed and were widely used by physicians for treating a range of ailments.
Flexner Report
For approximately half a century after the Flexner report 1910, the use of electricity, magnetism, and light for healing purposes was essentially illegal. The reorganization of medical education that followed the Flexner report led to a medicine that was focused on pharmaceuticals, and the economic and regulatory atmosphere put major emphasis on the development of new drugs while discouraging energetic approaches.
For approximately half a century after the Flexner report, the use of electricity, magnetism, and light for healing purposes was essentially illegal. The situation began to change in 1979 when the U.S. Food and Drug Administration (FDA) approved the use of pulsing electric, magnetic, and electromagnetic fields to stimulate bone healing. These methods followed from the work of Birch in London who used electricity to stimulate healing of bone fracture.
Electrical Stimulation
Becker has shown that very low levels of electrical stimulation can cause cultures of so-called differentiated cells to de-differentiate into totipotent cells capable of forming all of the tissues needed to replace a lost or damaged part. His fascinating description of this breakthrough research can be found in his book (Becker and Sheldon, 1985).
The key to Becker’s demonstration was reducing the strength of electrical stimulation. Following the usual way scientists tend to look at such matters, he assumed a large current would be more effective than a small one. The opposite was correct. In the experiments on frog red blood cells, conducted with a student named Frederick Brown, the test current was reduced, a step at a time, until they reached the lowest current the apparatus could produce, with the intensity control turned to zero, about half a billionth of an ampere. This stimulation produced a dramatic de- differentiation.
Current of Injury - Semiconductor Current
Becker’s research demonstrated that the current of injury is not an ionic current, but a semiconductor current that is sensitive to magnetic fields (the Hall effect). Semiconduction takes place in the perineural connective tissue and surrounding parts of the living matrix (Becker 1961).
--
In the last century, the studies performed by Fukada and Yasuda [2] and by Bassett and Becker [3] identified the relationship between mechanical loading and electrical activity in the bone, wherein lie the scientific origins of the electrical, magnetic, and mechanical stimulation of osteogenesis.
Following the discovery of piezoelectricity in bone by the Japanese surgeon/ physicist team of Yasuda and Fukada, it became evident, for reasons still unclear, that small currents in the order of fractions of a milliampere, when applied to such discontinuities, are able to initiate the required bone growth process. Bassett subsequently explored the use of pulsed electromagnetic fields (PEMF) to deal with this condition [4] obtaining a success rate of about 80%, and FDA approval, and at the same time demonstrating that this medical condition could be dealt with in a noninvasive manner.
1. Galvani L. De viribus electricitatis in motu musculari commen- tarius. Bologna: Ex typographia Instituti Scientiarum; 1791.
2. Fukada E, Yasuda I. On the piezoelectric effect of bone.
J Phys Soc Japan 1957;12:121–8.
3. Bassett CA, Becker RO. Generation of electric poten-
tials in bone in response to mechanical stress. Science
1962;137:1063–4.
4. Basset CAL, Pawluk RJ, Pilla AA. Augmentation of bone
repair by inductively coupled magnetic field. Science
1974;184:575–9.
It did not take very long for Galvani’s discoveries to be applied in medicine. One early discovery that has endured to this day is the use of electricity to stimulate the healing of bone fractures that have failed to heal. In 1812, Dr. John Birch in London healed a nonunion of the tibia with electric currents passed through needles surgically implanted in the fracture region. By the mid-1800s, this had become the preferred method for treating slow-healing bone fractures. A modern version of this treatment, widely preferred and used by orthopedic surgeons, is an implantable electrical stimulation device (Figure 5.7).
Medical electricity had its golden era between the late 1700s and the early 1900s. During that period, a variety of electrical healing devices were developed and were widely used by physicians for treating a range of ailments.
Flexner Report
For approximately half a century after the Flexner report 1910, the use of electricity, magnetism, and light for healing purposes was essentially illegal. The reorganization of medical education that followed the Flexner report led to a medicine that was focused on pharmaceuticals, and the economic and regulatory atmosphere put major emphasis on the development of new drugs while discouraging energetic approaches.
For approximately half a century after the Flexner report, the use of electricity, magnetism, and light for healing purposes was essentially illegal. The situation began to change in 1979 when the U.S. Food and Drug Administration (FDA) approved the use of pulsing electric, magnetic, and electromagnetic fields to stimulate bone healing. These methods followed from the work of Birch in London who used electricity to stimulate healing of bone fracture.
Electrical Stimulation
Becker has shown that very low levels of electrical stimulation can cause cultures of so-called differentiated cells to de-differentiate into totipotent cells capable of forming all of the tissues needed to replace a lost or damaged part. His fascinating description of this breakthrough research can be found in his book (Becker and Sheldon, 1985).
The key to Becker’s demonstration was reducing the strength of electrical stimulation. Following the usual way scientists tend to look at such matters, he assumed a large current would be more effective than a small one. The opposite was correct. In the experiments on frog red blood cells, conducted with a student named Frederick Brown, the test current was reduced, a step at a time, until they reached the lowest current the apparatus could produce, with the intensity control turned to zero, about half a billionth of an ampere. This stimulation produced a dramatic de- differentiation.
Current of Injury - Semiconductor Current
Becker’s research demonstrated that the current of injury is not an ionic current, but a semiconductor current that is sensitive to magnetic fields (the Hall effect). Semiconduction takes place in the perineural connective tissue and surrounding parts of the living matrix (Becker 1961).
--
In the last century, the studies performed by Fukada and Yasuda [2] and by Bassett and Becker [3] identified the relationship between mechanical loading and electrical activity in the bone, wherein lie the scientific origins of the electrical, magnetic, and mechanical stimulation of osteogenesis.
Following the discovery of piezoelectricity in bone by the Japanese surgeon/ physicist team of Yasuda and Fukada, it became evident, for reasons still unclear, that small currents in the order of fractions of a milliampere, when applied to such discontinuities, are able to initiate the required bone growth process. Bassett subsequently explored the use of pulsed electromagnetic fields (PEMF) to deal with this condition [4] obtaining a success rate of about 80%, and FDA approval, and at the same time demonstrating that this medical condition could be dealt with in a noninvasive manner.
1. Galvani L. De viribus electricitatis in motu musculari commen- tarius. Bologna: Ex typographia Instituti Scientiarum; 1791.
2. Fukada E, Yasuda I. On the piezoelectric effect of bone.
J Phys Soc Japan 1957;12:121–8.
3. Bassett CA, Becker RO. Generation of electric poten-
tials in bone in response to mechanical stress. Science
1962;137:1063–4.
4. Basset CAL, Pawluk RJ, Pilla AA. Augmentation of bone
repair by inductively coupled magnetic field. Science
1974;184:575–9.
In the middle of the 20th century, it was discovered that bone is piezoelectric in nature, and therefore was hypothesized to also transduce information electrically [23,24]. Soon thereafter, many experiments demonstrated that directly-applied electrical currents can be employed to induce bone formation and remodeling [12-14,25]. One problem with these early methods of direct electrical stimulation of bone tissue was that they required the implantation of electrodes into and around the bones to be stimulated. The deeply invasive nature of direct electrical stimulation of bone lead to the development of non-invasive methods, such as the use of induced electrical fields. These inductive methods employ magnetic fields from external magnets or solenoids that change over time to induce the desired electrical fields within the tissues, based on the well- understood Faraday’s Law of Induction [66]. Electrical fields induced in this non-invasive manner were subsequently shown to be effective in eliciting accelerated bone formation and healing [12].
Delicate Balance - Need enough but avoid heating/depolarization
PEMF relies on generation of local potential gradients and electric currents that would mimic bone electrochemical responses to load [14,15]. Achieving a delicate balance between the local electrical currents sufficiently high to trigger biological responses without introducing undesirable heating effects (to avoid diathermy) is a challenging bioengineering problem, approached either by a direct current application through skin contact electrodes (“capacitive coupling”) or by a contact-less “inductive coupling”, as used in our work [16]. This raises an important question about the PEMF safe dose required for achieving measurable effects in vivo in a mammalian model of osteoporosis that this study is designed to address.
Delicate Balance - Need enough but avoid heating/depolarization
PEMF relies on generation of local potential gradients and electric currents that would mimic bone electrochemical responses to load [14,15]. Achieving a delicate balance between the local electrical currents sufficiently high to trigger biological responses without introducing undesirable heating effects (to avoid diathermy) is a challenging bioengineering problem, approached either by a direct current application through skin contact electrodes (“capacitive coupling”) or by a contact-less “inductive coupling”, as used in our work [16]. This raises an important question about the PEMF safe dose required for achieving measurable effects in vivo in a mammalian model of osteoporosis that this study is designed to address.
Benefits of PEMF over Microcurrent
--- Better Microcurrent Therapy
1) No invasive electrodes needed
2) Penetrates deeper
3) Larger Volume covered and more even distribution
One final advantage of PEMF over more general forms of microcurrent stimulation is that when properly applied, high slew rate PEMF pulses are transformed into induced electrical signals that themselves mimic known electrical signals within living tissues, such as those involved in excitation-contraction coupling of striated muscle (skeletal and cardiac muscle), therefore PEMF can take advantage of native signal reception and amplification mechanisms within living cells/tissues, thus requiring only very low stimulation energy to achieve the desired cellular response.
Body is Transparent to a Magnetic Field. Body does not reduce through body. Like wind blowing through a field of grass. Low Frequencies go all the way through. Long wavelengths PEMF Treats entire volume of body, not just surface.
Body not copper but very conducive
Use tube voltage toy.
Piezoelectric collagen
Ions in paramembrane space
Ion transport
Magnetite
--- Better Microcurrent Therapy
1) No invasive electrodes needed
2) Penetrates deeper
3) Larger Volume covered and more even distribution
One final advantage of PEMF over more general forms of microcurrent stimulation is that when properly applied, high slew rate PEMF pulses are transformed into induced electrical signals that themselves mimic known electrical signals within living tissues, such as those involved in excitation-contraction coupling of striated muscle (skeletal and cardiac muscle), therefore PEMF can take advantage of native signal reception and amplification mechanisms within living cells/tissues, thus requiring only very low stimulation energy to achieve the desired cellular response.
Body is Transparent to a Magnetic Field. Body does not reduce through body. Like wind blowing through a field of grass. Low Frequencies go all the way through. Long wavelengths PEMF Treats entire volume of body, not just surface.
Body not copper but very conducive
Use tube voltage toy.
Piezoelectric collagen
Ions in paramembrane space
Ion transport
Magnetite
8-4. Mechanisms of action
**Mechanism 1**Specific - Calcium-Calmodulin (Ca2+/CaM) dependent nitric-oxide synthase pathway [2,5,7-9,17-21]. Specifically, it is hypothesized that electromagnetic pulses of appropriate parameters will preferentially induce calcium binding to CaM
PEMF stimulation fine-tunes growth factors in many ways, but one of the best-understood is by increasing nitric oxide production. Calmodulin (CaM) is a messenger protein in the cell that binds calcium. It mediates various biologic processes. Once CaM binds to calcium (a process PEMF therapy increases by supporting the necessary electrical charge activity), the resulting cascade catalyzes the release of nitric oxide, and therefore improves growth factors.
1. modulation of calmodulin (CaM)- dependent nitric oxide [4],
Observations and mathematical models suggest that one of the primary anti-inflammatory mechanisms of ICES is via the Calcium-Calmodulin (Ca2+/CaM) dependent nitric-oxide synthase pathway [2,5,7-9,17-21]. Specifically, it is hypothesized that electromagnetic pulses of appropriate parameters will preferentially induce calcium binding to CaM [7]
The proposed mechanism is that PEMF accelerates the binding of cytosolic Ca2+ to CaM in a cell, which has been challenged physically or chemically, leading to a transient increase in NO, which in turn enhances a transient increase in cGMP release. PEMF modulation of CaM/NO/cGMP signaling can lead to more rapid resolution of inflammation. This proposed mechanism is outlined in Figure 18.1. Several peer-reviewed studies at the cellular level support this mechanism (Pilla et al., 1999, 2011; Pilla, 2007, 2011, 2012, 2013).
Pilla AA. Mechanisms and therapeutic applications of time varying and static magnetic fields. In Biological and Medical Aspects of Electromagnetic Fields, Barnes F, Greenebaum B, (eds.). CRC Press: Boca Raton, FL. 2007; pp. 351–411.
Pilla AA. Electromagnetic fields instantaneously modulate nitric oxide signaling in challenged biological systems. Biochem Biophys Res Commun. 2012;426:330–333.
Pilla AA. Nonthermal electromagnetic fields: From first messenger to therapeutic applications. Electromagn Biol Med. 2013;32:123–136.
Pilla A, Fitzsimmons R, Muehsam D, Wu J, Rohde C, Casper D. Electromagnetic fields as first messenger in biological signaling: Application to calmodulin-dependent signaling in tissue repair. Biochim Biophys Acta. 2011;1810:1236–1245.
Pilla AA, Muehsam DJ, Markov MS, Sisken BF. EMF signals and ion/ligand binding kinetics: Prediction of bioeffective waveform parameters. Bioelectrochem Bioenerg. 1999;48:27–34.
**Mechanism 1**Specific - Calcium-Calmodulin (Ca2+/CaM) dependent nitric-oxide synthase pathway [2,5,7-9,17-21]. Specifically, it is hypothesized that electromagnetic pulses of appropriate parameters will preferentially induce calcium binding to CaM
PEMF stimulation fine-tunes growth factors in many ways, but one of the best-understood is by increasing nitric oxide production. Calmodulin (CaM) is a messenger protein in the cell that binds calcium. It mediates various biologic processes. Once CaM binds to calcium (a process PEMF therapy increases by supporting the necessary electrical charge activity), the resulting cascade catalyzes the release of nitric oxide, and therefore improves growth factors.
1. modulation of calmodulin (CaM)- dependent nitric oxide [4],
Observations and mathematical models suggest that one of the primary anti-inflammatory mechanisms of ICES is via the Calcium-Calmodulin (Ca2+/CaM) dependent nitric-oxide synthase pathway [2,5,7-9,17-21]. Specifically, it is hypothesized that electromagnetic pulses of appropriate parameters will preferentially induce calcium binding to CaM [7]
The proposed mechanism is that PEMF accelerates the binding of cytosolic Ca2+ to CaM in a cell, which has been challenged physically or chemically, leading to a transient increase in NO, which in turn enhances a transient increase in cGMP release. PEMF modulation of CaM/NO/cGMP signaling can lead to more rapid resolution of inflammation. This proposed mechanism is outlined in Figure 18.1. Several peer-reviewed studies at the cellular level support this mechanism (Pilla et al., 1999, 2011; Pilla, 2007, 2011, 2012, 2013).
Pilla AA. Mechanisms and therapeutic applications of time varying and static magnetic fields. In Biological and Medical Aspects of Electromagnetic Fields, Barnes F, Greenebaum B, (eds.). CRC Press: Boca Raton, FL. 2007; pp. 351–411.
Pilla AA. Electromagnetic fields instantaneously modulate nitric oxide signaling in challenged biological systems. Biochem Biophys Res Commun. 2012;426:330–333.
Pilla AA. Nonthermal electromagnetic fields: From first messenger to therapeutic applications. Electromagn Biol Med. 2013;32:123–136.
Pilla A, Fitzsimmons R, Muehsam D, Wu J, Rohde C, Casper D. Electromagnetic fields as first messenger in biological signaling: Application to calmodulin-dependent signaling in tissue repair. Biochim Biophys Acta. 2011;1810:1236–1245.
Pilla AA, Muehsam DJ, Markov MS, Sisken BF. EMF signals and ion/ligand binding kinetics: Prediction of bioeffective waveform parameters. Bioelectrochem Bioenerg. 1999;48:27–34.
**Mechanism 2** - Adenosine - A2A receptors - cAMP - anti-inflammatory
In vitro analysis of BS has documented considerable results on various cellular models. In two studies on human neutrophils, BS creates a strong adenosine-agonist effect specific for the A2A and A3 receptors [101,102]. This effect, mediated by the increase in the number of receptors themselves, determines a significant increase in the cyclical AMP (cAMP) and a reduction in the release of super- oxide anion (O2−) suggesting an anti-inflammatory effect. This mechanism of action has been confirmed in chondrocyte and synoviocyte cultures [103,104].
101. Varani K, Gessi S, Merighi S, Iannotta V, Cattabriga E, Spisani S, Cadossi R, Borea PA. Effect of low frequency electromagnetic fields on A2A adenosine receptors in human neutrophils. Br J Pharmacol. 2002;136(1):57–66.
102. Varani K, Gessi S, Merighi S, Iannotta V, Cattabriga E, Pancaldi C, Cadossi R, Borea PA. Alteration of A3 adenosine receptors in human neutrophils and low frequency electromagnetic fields. Biochem Pharmacol. 2003;66(10):1897–1906.
103. Varani K, De Mattei M, Vincenzi F, Gessi S, Merighi S, Pellati A, Ongaro A, Caruso A, Cadossi R, Borea PA. Characterization of adenosine receptors in bovine chondrocytes and fibroblast-like synovi- ocytes exposed to low frequency low energy pulsed electromagnetic fields. Osteoarthritis Cartilage. 2008;16(3):292–304.
104. Vincenzi F, Targa M, Corciulo C, Gessi S, Merighi S, Setti S, Cadossi R, Goldring MB, Borea PA, Varani K. Pulsed electromagnetic fields increased the anti-inflammatory effect of A2A and A3 adenosine recep- tors in human T/C-28a2 chondrocytes and hFOB 1.19 osteoblasts. PLoS ONE. 2013;8(5):e65561. doi: 10.1371/journal.pone.0065561. Print 2013.
In vitro analysis of BS has documented considerable results on various cellular models. In two studies on human neutrophils, BS creates a strong adenosine-agonist effect specific for the A2A and A3 receptors [101,102]. This effect, mediated by the increase in the number of receptors themselves, determines a significant increase in the cyclical AMP (cAMP) and a reduction in the release of super- oxide anion (O2−) suggesting an anti-inflammatory effect. This mechanism of action has been confirmed in chondrocyte and synoviocyte cultures [103,104].
101. Varani K, Gessi S, Merighi S, Iannotta V, Cattabriga E, Spisani S, Cadossi R, Borea PA. Effect of low frequency electromagnetic fields on A2A adenosine receptors in human neutrophils. Br J Pharmacol. 2002;136(1):57–66.
102. Varani K, Gessi S, Merighi S, Iannotta V, Cattabriga E, Pancaldi C, Cadossi R, Borea PA. Alteration of A3 adenosine receptors in human neutrophils and low frequency electromagnetic fields. Biochem Pharmacol. 2003;66(10):1897–1906.
103. Varani K, De Mattei M, Vincenzi F, Gessi S, Merighi S, Pellati A, Ongaro A, Caruso A, Cadossi R, Borea PA. Characterization of adenosine receptors in bovine chondrocytes and fibroblast-like synovi- ocytes exposed to low frequency low energy pulsed electromagnetic fields. Osteoarthritis Cartilage. 2008;16(3):292–304.
104. Vincenzi F, Targa M, Corciulo C, Gessi S, Merighi S, Setti S, Cadossi R, Goldring MB, Borea PA, Varani K. Pulsed electromagnetic fields increased the anti-inflammatory effect of A2A and A3 adenosine recep- tors in human T/C-28a2 chondrocytes and hFOB 1.19 osteoblasts. PLoS ONE. 2013;8(5):e65561. doi: 10.1371/journal.pone.0065561. Print 2013.
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8-4. Mechanisms of action
Properly configured PEMF signals have been demonstrated to regulate major cellular functions, including cell proliferation, differentiation, apoptosis, cell cycle, DNA replication, and cytokine/chemokine expression [1-3].
Among the possible mechanisms of PEMF-induced influence on the biological systems are
2. increase in expression of protective stress protein hsp70 gene [5],
3. and downregulation of proinflammatory NF-kB signaling pathway [6]
[5] George, I., Geddis, M.S., Lill, Z., Lin, H., Gomez, T., Blank, M., Oz, M.C., and Goodman, R. (2008). Myocardial function improved by electromagnetic field induction of stress protein hsp70. J Cell Physiol 216, 816–823.
[6] Vianale, G., Reale, M., Amerio, P., Stefanachi, M., Di Luzio, S., and Muraro, R. (2008). Extremely low frequency electromagnetic field enhances human keratinocyte cell growth and decreases proinflammatory chemokine production. Br J Dermatol 158, 1189–1196.
**Heat Shock Proteins**
cyto-protective (cell protection) proteins, such as heat shock protein 70 (hsp70), when tissues are placed in biologically active magnetic fields. Heat shock proteins (HSPs) are a family of proteins that protect cells from stress and help other proteins function:
Stress response: HSPs are produced by cells when exposed to stressful conditions, such as heat, cold, UV light, low oxygen, or low glucose.
Protein folding: HSPs help other proteins fold, assemble, and disassemble.
Cell adaptation: HSPs help cells adapt to environmental and endogenous stresses.
DNA repair: HSPs are involved in DNA repair signaling pathways.
[1] Aaron, R.K., Boyan, B.D., Ciombor, D.M., Schwartz, Z., and Simon, B.J. (2004). Stimulation of growth factor synthesis by electric and electromagnetic fields. Clin Orthop Relat Res 419, 30–37.
[2] Pesce, M., Patruno, A., Speranza, L., and Reale, M. (2013). Extremely low frequency electromagnetic field and wound healing: Implication of cytokines as biological mediators. Eur Cytokine Netw 24, 1–10.
[3] Pena-Philippides, J.C., Yang, Y., Bragina, O., Hagberg, S., Nemoto, E., and Roitbak, T. (2014). Effect of pulsed electromagnetic field (PEMF) on infarct size and inflammation after cerebral ischemia in mice. Transl Stroke Res 5, 491–500.
[4] Pilla, A.A. (2012). Electromagnetic fields instantaneously modulate nitric oxide signaling in challenged bio- logical systems. Biochem Biophys Res Commun 426, 330–333.
[5] George, I., Geddis, M.S., Lill, Z., Lin, H., Gomez, T., Blank, M., Oz, M.C., and Goodman, R. (2008). Myocardial function improved by electromagnetic field induction of stress protein hsp70. J Cell Physiol 216, 816–823.
[6] Vianale, G., Reale, M., Amerio, P., Stefanachi, M., Di Luzio, S., and Muraro, R. (2008). Extremely low frequency electromagnetic field enhances human keratinocyte cell growth and decreases proinflammatory chemokine production. Br J Dermatol 158, 1189–1196.
Properly configured PEMF signals have been demonstrated to regulate major cellular functions, including cell proliferation, differentiation, apoptosis, cell cycle, DNA replication, and cytokine/chemokine expression [1-3].
Among the possible mechanisms of PEMF-induced influence on the biological systems are
2. increase in expression of protective stress protein hsp70 gene [5],
3. and downregulation of proinflammatory NF-kB signaling pathway [6]
[5] George, I., Geddis, M.S., Lill, Z., Lin, H., Gomez, T., Blank, M., Oz, M.C., and Goodman, R. (2008). Myocardial function improved by electromagnetic field induction of stress protein hsp70. J Cell Physiol 216, 816–823.
[6] Vianale, G., Reale, M., Amerio, P., Stefanachi, M., Di Luzio, S., and Muraro, R. (2008). Extremely low frequency electromagnetic field enhances human keratinocyte cell growth and decreases proinflammatory chemokine production. Br J Dermatol 158, 1189–1196.
**Heat Shock Proteins**
cyto-protective (cell protection) proteins, such as heat shock protein 70 (hsp70), when tissues are placed in biologically active magnetic fields. Heat shock proteins (HSPs) are a family of proteins that protect cells from stress and help other proteins function:
Stress response: HSPs are produced by cells when exposed to stressful conditions, such as heat, cold, UV light, low oxygen, or low glucose.
Protein folding: HSPs help other proteins fold, assemble, and disassemble.
Cell adaptation: HSPs help cells adapt to environmental and endogenous stresses.
DNA repair: HSPs are involved in DNA repair signaling pathways.
[1] Aaron, R.K., Boyan, B.D., Ciombor, D.M., Schwartz, Z., and Simon, B.J. (2004). Stimulation of growth factor synthesis by electric and electromagnetic fields. Clin Orthop Relat Res 419, 30–37.
[2] Pesce, M., Patruno, A., Speranza, L., and Reale, M. (2013). Extremely low frequency electromagnetic field and wound healing: Implication of cytokines as biological mediators. Eur Cytokine Netw 24, 1–10.
[3] Pena-Philippides, J.C., Yang, Y., Bragina, O., Hagberg, S., Nemoto, E., and Roitbak, T. (2014). Effect of pulsed electromagnetic field (PEMF) on infarct size and inflammation after cerebral ischemia in mice. Transl Stroke Res 5, 491–500.
[4] Pilla, A.A. (2012). Electromagnetic fields instantaneously modulate nitric oxide signaling in challenged bio- logical systems. Biochem Biophys Res Commun 426, 330–333.
[5] George, I., Geddis, M.S., Lill, Z., Lin, H., Gomez, T., Blank, M., Oz, M.C., and Goodman, R. (2008). Myocardial function improved by electromagnetic field induction of stress protein hsp70. J Cell Physiol 216, 816–823.
[6] Vianale, G., Reale, M., Amerio, P., Stefanachi, M., Di Luzio, S., and Muraro, R. (2008). Extremely low frequency electromagnetic field enhances human keratinocyte cell growth and decreases proinflammatory chemokine production. Br J Dermatol 158, 1189–1196.
- Reverse Piezoelectric Effect - microvibrations!
- Microcurrents interrupt pain signal. Faster slew rates could lead to more significant pain relief by disrupting pain transmission at a quicker rate.
- Cell membrane one way rectifier - ion transport
- Increases ATP 400%
- Nitric Oxide and increased microcirculation
- Electroporesis - Increased cell permeability may occur, allowing for improved nutrient uptake and waste removal. Cells Breathing Better... Oxygen nutrients in easier
- Catalyst chemical reactions.
- Exercise Mimetic - LOAD/STRESS PIEZOELECTRIC. Circuits are in ions in paramembrane space. Receptors on Cell membrane that detect this ionic movement and sense it as normal exercise.
- Healing is voltage salamander studies
Crystalline Arrangements are the rule and not the exception in living systems. So MUSCLES, TENDONS, Bones, myelin, muscle, sensory organs and even cell membrane crystalline and therefore piezoelectric properties.
Virtually all the tissues in the body produce an electric field when they are stretched or compressed = ENERGY! These oscillating fields correspond precisely to the input stressors which mean they contain the information. This information is electrically and electronically conducted through the living matrix.
The electric fields produced during movements are widely considered to provide the information that directs the activities of generative cells (Bassett). These osteoblasts, myoblasts, fibroblasts and other 'stem' cells help to reform and heal tissues so the body can adapt to ways the body is used.
Electric fields generated during movement (streaming or piezoelectric potentials) or PEMF signal cells (fibroblasts in connective tissue, osteoblasts in bones) to lay down collagen in the direction of tension/stress and therefore strengthen the tissue. With less loading or movement, the electric fields are weaker and less frequent, and the cells resorb collagen (Bassett 1968).
-Cells Breathing Better... Oxygen nutrients in easier,
- Chronic Inflammation
8 Hour test - carrageenan challenge to lower inflammation.
60% as effective as a megadose of steroids.
No measurable effect on inflammation.
Most exciting results he had seen.
The fundamental action of PEMF appears to be the reduction of pathologic chronic inflammation to enable normal tissue recovery. So, it is better to think of PEMF as something that improves the physiologic conditions to promote normal healing, rather than as an external force that “heals something”. Thinking along these lines, my conceptualization is that healing in joints is facilitated by PEMF by suppressing pathologic inflammation and swelling. This allows normal healing processes to occur. But the “normal” healing rate for joint tissues is extremely slow, so it is not likely that PEMF would drive the healing process quickly in terms of joint healing. PEMF just helps to facilitate what is normally a slow, natural process.
PEMF exposure results in increased expression of adenosine receptors in a variety of cells and tissues. Activation of these receptors results in reduction of prostaglandins , reduction of inflammatory cytokines in alignment with published studies of decrease pain and inflammation and increased wound healing.
- Reverse Piezoelectric Effect - microvibrations!
- Microcurrents interrupt pain signal. Faster slew rates could lead to more significant pain relief by disrupting pain transmission at a quicker rate.
- Cell membrane one way rectifier - ion transport
- Increases ATP 400%
- Nitric Oxide and increased microcirculation
- Electroporesis - Increased cell permeability may occur, allowing for improved nutrient uptake and waste removal. Cells Breathing Better... Oxygen nutrients in easier
- Catalyst chemical reactions.
- Exercise Mimetic - LOAD/STRESS PIEZOELECTRIC. Circuits are in ions in paramembrane space. Receptors on Cell membrane that detect this ionic movement and sense it as normal exercise.
- Healing is voltage salamander studies
Crystalline Arrangements are the rule and not the exception in living systems. So MUSCLES, TENDONS, Bones, myelin, muscle, sensory organs and even cell membrane crystalline and therefore piezoelectric properties.
Virtually all the tissues in the body produce an electric field when they are stretched or compressed = ENERGY! These oscillating fields correspond precisely to the input stressors which mean they contain the information. This information is electrically and electronically conducted through the living matrix.
The electric fields produced during movements are widely considered to provide the information that directs the activities of generative cells (Bassett). These osteoblasts, myoblasts, fibroblasts and other 'stem' cells help to reform and heal tissues so the body can adapt to ways the body is used.
Electric fields generated during movement (streaming or piezoelectric potentials) or PEMF signal cells (fibroblasts in connective tissue, osteoblasts in bones) to lay down collagen in the direction of tension/stress and therefore strengthen the tissue. With less loading or movement, the electric fields are weaker and less frequent, and the cells resorb collagen (Bassett 1968).
-Cells Breathing Better... Oxygen nutrients in easier,
- Chronic Inflammation
8 Hour test - carrageenan challenge to lower inflammation.
60% as effective as a megadose of steroids.
No measurable effect on inflammation.
Most exciting results he had seen.
The fundamental action of PEMF appears to be the reduction of pathologic chronic inflammation to enable normal tissue recovery. So, it is better to think of PEMF as something that improves the physiologic conditions to promote normal healing, rather than as an external force that “heals something”. Thinking along these lines, my conceptualization is that healing in joints is facilitated by PEMF by suppressing pathologic inflammation and swelling. This allows normal healing processes to occur. But the “normal” healing rate for joint tissues is extremely slow, so it is not likely that PEMF would drive the healing process quickly in terms of joint healing. PEMF just helps to facilitate what is normally a slow, natural process.
PEMF exposure results in increased expression of adenosine receptors in a variety of cells and tissues. Activation of these receptors results in reduction of prostaglandins , reduction of inflammatory cytokines in alignment with published studies of decrease pain and inflammation and increased wound healing.
**Bone - Currents of Injury and Currents of Healing [cont]*
The scientific origins of the BS techniques for bone healing are acknowledged to lie in the by now classic studies performed first by Fukada and Yasuda [1], then by Bassett and Becker [2]; study of the effect of BS techniques for cartilage healing is more recent [3].
The aforementioned studies performed in the 1950s and 1960s highlighted the relation between bone tissue mechanical deformation and electric potentials. The signal induced by structural (mechanical) deformation following the application of a load is present in bone, not necessarily vital, and can be ascribed to a dual origin: (1) to the direct piezoelectric effect and (2) to the electrokinetic phenomenon of the flow potential [4–10]. The electrical signal induced by the mechanical deformation has been considered to be the transducer of a physical force in a cell response and has been taken to be the mechanism that determines the continuous adaptation of the mechanical competence of bone to variations in load, according to the well- known Wolff’s law [11].
In the absence of mechanical stress, vital bone generates an electrical signal detectable in vivo as surface stationary bioelectric potential and ex vivo as stationary electric (ionic) current that can be measured [12–20].
On the basis of these premises, biophysical enhancement of osteogenesis with different stimuli has been developed: pulsed electromagnetic field (PEMF, inductive system), capacitive-coupling electric field (CCEF, capacitive system), and the use of low-intensity pulsed ultrasound (LIPU, ultra- sound system).
Various authors agree on the fact that the cell membrane plays the fundamental role in recognizing and transferring the physical stimulus to the various metabolic pathways of the cell; by this mechanism of action, a cell recognizes a physical stimulus and thus modifies its functions. The PEMF stimulation causes the liberation of calcium ions (Ca++) from the smooth endoplasmic reticulum.
The intracellular increase of the Ca++ determines a series of enzyme responses with resulting gene transcription (several bone morphogenetic proteins [BMPs], trans- forming growth factor-beta [TGF-β1], and collagen) and cell proliferation [22]. Upregulation of TGF-β1 mRNA expression has been reported in mechanically loaded bones; different groups have demonstrated increases in proliferation, differentiation, and transcription of mRNA for several BMPs and TGF-βs in skeletal tissue with all biophysical system exposure [23–41]. The application of physical stimuli results in changes in gene expression for signaling proteins.
In vitro studies have shown that the physical stimuli increase the synthesis of bone matrix and favor the proliferation and differentiation of the osteoblast-like primary cells [42,43]. Fassina et al. investigated the effect of PEMF on SAOS-2 human osteoblast proliferation and on calcified matrix production over a polyurethane porous scaffold and showed a higher cell proliferation and a greater expression of decorin, fibronectin, osteocalcin, osteopontin, TGF-β1, type I collagen, and type III collagen in PEMF-stimulated culture than in controls [28].
1. Fukada E, Yasuda I. On the piezoelectric effect of bone. J Phys Soc Jpn. 1957;12:121–128.
2. Bassett CA, Becker RO. Generation of electric potentials in bone in response to mechanical stress. Science. 1962;137:1063–1064.
3. Xu J, Wang W, Clark CC, Brighton CT. Signal transduction in electrically stimulated articular chondrocytes involves translocation of extracellular calcium through voltage-gated channels. Osteoarthritis Cart. 2009;17(3):397–405.
4. Galvani L. De viribus electricitatis in motu musculari commentarius. Bologna, Italy: Ex typographia. Instituti Scientiarum, 1791.
5. Black J. Electrical Stimulation. New York: Praeger, 1987.
6. Guzelsu N. Piezoelectric and electrokinetic effects in bone tissue. Electro Magnet Biol. 1993;12(1):51–82. Review.
7. Green J, Kleeman CR. Role of bone in regulation of systemic acid-base balance. Kidney Int. 1991;39:9–26.
8. Otter MW, Vincent R, Palmieri VR, Dadong DWu, Seiz KG, Mac Ginitie LA, Cochran GVB. A comparative analysis of streaming potentials in vivo and in vitro. J Orthopaedic Res. 1992;10:710–719.
9. Pollack SR. Bioelectrical properties of bone. Endogenous electrical signals. Orthop Clin North Am.1984;15:3–14.
10. Behari J. Electrostimulation and bone fracture healing. Biomed Eng. 1992;18:235–254.
11. Wolff J. Das Gesetz der Transformation der Knochen. Berlin, Germany: Hirschwald, 1892.
12. Friedenberg ZB, Brighton CT. Bioelectric potentials in bone. J Bone Joint Surg Am. 1966;48(5):915–923.
13. Friedenberg ZB, Dyer R, Brighton CT. Electro-osteograms of long bones of immature rabbits. J Dent Res. 1971;50(3):635–639.
14. Friedenberg ZB, Harlow MC, Heppenstall R, Brighton CT. The cellular origin of bioelectric potentials in bone. Calcif Tissue Res. 1973;13(1):53–62.
15. Rubinacci A, Brigatti L, Tessari L. A reference curve for axial bioelectric potentials in adult rabbit tibia. Bioelectromagnetics. 1984;5(2):193–202.
16. Chakkalakal DA, Wilson RF, Connolly JF. Epidermal and endosteal sources of endogenous electricity in injured canine limbs. IEEE Trans Biomed Eng. 1988;35(1):19–30.
17. Lokietek W, Pawluk RF, Bassett CA. Muscle injury potentials: A source of voltage in the undeformed rabbit tibia. J Bone Joint Surg Br. 1974;56(2):361–369.
18.Borgens RB. Endogenous ionic currents traverse intact and damaged bone. Science.
1984;225(4661):478–482.
19. De Ponti A, Villa I, Boniforti F, Rubinacci A. Ionic currents at the growth plate of intact bone: occurrence and ionic dependence. Electro- Magneto Biol. 1996;15(1):37–48.
20. Rubinacci A, De Ponti A, Shipley A, Samaja M, Karplus E, Jaffe LF. Bicarbonate dependence of ion current in damaged bone. Calcif Tissue Int. 1996;58:423–428.
21. Aaron RK, Boyan BD, Ciombor DM, Schwartz Z, Simon BJ. Stimulation of growth factor synthesis by electric and electromagnetic fields. Clin Orthop Relat Res. 2004;(419):30–37. Review.
22. Brighton CT, Wang W, Seldes R, Zhang G, Pollack SR. Signal transduction in electrically stimulated bone cells. J Bone Joint Surg Am. 2001;83-A(10):1514–1523.
23. Nagai M, Ota M. Pulsating electromagnetic field stimulates mRNA expression of bone morphogenetic protein -2 and -4. J Dental Res. 1994;73:1601–1605.
24. Bodamyali T, Bhatt B, Hughes FJ, Winrow VR, Kanczler JM, Simon B, Abbott J, Blake DR, Stevens CR. Pulsed electromagnetic fields simultaneously induce osteogenesis and upregulate transcription of bone morphogenetic proteins 2 and 4 in rat osteoblasts in vitro. Biochem Biophys Res Commun. 1998;250(2):458–461.
25. Guerkov HH1, Lohmann CH, Liu Y, Dean DD, Simon BJ, Heckman JD, Schwartz Z, Boyan BD. Pulsed electromagnetic fields increase growth factor release by nonunion cells. Clin Orthop Relat Res. 2001;(384):265–279.
26. Aaron RK, Ciombor DM, Keeping H, Wang S, Capuano A, Polk C. Power frequency fields promote cell differentiation coincident with an increase in transforming growth factor-beta(1) expression. Bioelectromagnetics. 1999;20(7):453–458. Erratum in: Bioelectromagnetics. 2000;21(1):73.
27. Lohmann CH, Schwartz Z, Liu Y, Guerkov H, Dean DD, Simon B, Boyan BD. Pulsed electromag- netic field stimulation of MG63 osteoblast-like cells affects differentiation and local factor production. J Orthop Res. 2000;18(4):637–646.
28. Fassina L, Visai L, Benazzo F, Benedetti L, Calligaro A, De Angelis MG, Farina A, Maliardi V, Magenes G. Effects of electromagnetic stimulation on calcified matrix production by SAOS-2 cells over a polyurethane porous scaffold. Tissue Eng. 2006;12(7):1985–1999.
29. Jansen JH, van der Jagt OP, Punt BJ, Verhaar JA, van Leeuwen JP, Weinans H, Jahr H. Stimulation of osteogenic differentiation in human osteoprogenitor cells by pulsed electromagnetic fields: An in vitro study. BMC Musculoskelet Disord. 2010;11:188.
30. Esposito M, Lucariello A, Riccio I, Riccio V, Esposito V, Riccardi G. Differentiation of human osteopro- genitor cells increases after treatment with pulsed electromagnetic fields. In Vivo. 2012;26(2):299–304.
31. Ceccarelli G, Bloise N, Mantelli M, Gastaldi G, Fassina L, De Angelis MG, Ferrari D, Imbriani M, Visai L. A comparative analysis of the in vitro effects of pulsed electromagnetic field treatment on osteo- genic differentiation of two different mesenchymal cell lineages. Biores Open Access. 2013;2(4):283–294.
32. Lim K, Hexiu J, Kim J, Seonwoo H, Cho WJ, Choung PH, Chung JH. Effects of electromagnetic fields on osteogenesis of human alveolar bone-derived mesenchymal stem cells. Biomed Res Int. 2013;2013:296019. doi: 10.1155/2013/296019. Epub 2013 Jun 19.
33. Zhou J, Wang JQ, Ge BF, Ma XN, Ma HP, Xian CJ, Chen KM. Different electromagnetic field wave- forms have different effects on proliferation, differentiation and mineralization of osteoblasts in vitro. Bioelectromagnetics. 2013. doi: 10.1002/bem.21794.
34. Zhuang H, Wang W, Seldes RM, Tahernia AD, Fan H, Brighton CT. Electrical stimulation induces the level of TGF-β1 mRNA in osteoblastic cells by a mechanism involving calcium/calmodulin pathway. Biochem Biophys Res Comm. 1997;237:225–229.
35. Hartig M, Joos U, Wiesmann HP. Capacitively coupled electric fields accelerate proliferation of osteoblast-like primary cells and increase bone extracellular matrix formation in vitro. Eur Biophys J. 2000;29(7):499–506.
36. Wang Z, Clark CC, Brighton CT. Up-regulation of bone morphogenetic proteins in cultured murine bone cells with use of specific electric fields. J Bone Joint Surg Am. 2006;88(5):1053–1065.
37. Bisceglia B, Zirpoli H, Caputo M, Chiadini F, Scaglione A, Tecce MF. Induction of alkaline phosphatase activity by exposure of human cell lines to a low-frequency electric field from apparatuses used in clinical therapies. Bioelectromagnetics. 2011;32(2):113–119.
38. Clark CC, Wang W, Brighton CT. Up-regulation of expression of selected genes in human bone cells with specific capacitively coupled electric fields. J Orthop Res. July 2014; 32(7):894–903.
39. Hauser J, Hauser M, Muhr G, Esenwein S. Ultrasound-induced modifications of cytoskeletal components in osteoblast-like SAOS-2 cells. J Orthop Res. 2009;27(3):286–294.
40. Fassina L, Saino E, De Angelis MG, Magenes G, Benazzo F, Visai L. Low-power ultrasounds as a tool to culture human osteoblasts inside cancellous hydroxyapatite. Bioinorg Chem Appl. 2010:456240. doi: 10.1155/2010/456240. Epub 2010 Mar 31.
41. Xue H, Zheng J, Cui Z et al. Low-intensity pulsed ultrasound accelerates tooth movement via activation of the BMP-2 signaling pathway. PLoS ONE. 2013;8(7):e68926.
42. Aaron RK, Ciombor DM. Acceleration of experimental endochondral ossification by biophysical stimu- lation of the progenitor cell pool. J Orthop Res. 1996;14(4):582–589.
43. Ciombor DM, Aaron RK. The role of electrical stimulation in bone repair. Foot Ankle Clin. 2005;10(4): 579–593. Review.
The scientific origins of the BS techniques for bone healing are acknowledged to lie in the by now classic studies performed first by Fukada and Yasuda [1], then by Bassett and Becker [2]; study of the effect of BS techniques for cartilage healing is more recent [3].
The aforementioned studies performed in the 1950s and 1960s highlighted the relation between bone tissue mechanical deformation and electric potentials. The signal induced by structural (mechanical) deformation following the application of a load is present in bone, not necessarily vital, and can be ascribed to a dual origin: (1) to the direct piezoelectric effect and (2) to the electrokinetic phenomenon of the flow potential [4–10]. The electrical signal induced by the mechanical deformation has been considered to be the transducer of a physical force in a cell response and has been taken to be the mechanism that determines the continuous adaptation of the mechanical competence of bone to variations in load, according to the well- known Wolff’s law [11].
In the absence of mechanical stress, vital bone generates an electrical signal detectable in vivo as surface stationary bioelectric potential and ex vivo as stationary electric (ionic) current that can be measured [12–20].
On the basis of these premises, biophysical enhancement of osteogenesis with different stimuli has been developed: pulsed electromagnetic field (PEMF, inductive system), capacitive-coupling electric field (CCEF, capacitive system), and the use of low-intensity pulsed ultrasound (LIPU, ultra- sound system).
Various authors agree on the fact that the cell membrane plays the fundamental role in recognizing and transferring the physical stimulus to the various metabolic pathways of the cell; by this mechanism of action, a cell recognizes a physical stimulus and thus modifies its functions. The PEMF stimulation causes the liberation of calcium ions (Ca++) from the smooth endoplasmic reticulum.
The intracellular increase of the Ca++ determines a series of enzyme responses with resulting gene transcription (several bone morphogenetic proteins [BMPs], trans- forming growth factor-beta [TGF-β1], and collagen) and cell proliferation [22]. Upregulation of TGF-β1 mRNA expression has been reported in mechanically loaded bones; different groups have demonstrated increases in proliferation, differentiation, and transcription of mRNA for several BMPs and TGF-βs in skeletal tissue with all biophysical system exposure [23–41]. The application of physical stimuli results in changes in gene expression for signaling proteins.
In vitro studies have shown that the physical stimuli increase the synthesis of bone matrix and favor the proliferation and differentiation of the osteoblast-like primary cells [42,43]. Fassina et al. investigated the effect of PEMF on SAOS-2 human osteoblast proliferation and on calcified matrix production over a polyurethane porous scaffold and showed a higher cell proliferation and a greater expression of decorin, fibronectin, osteocalcin, osteopontin, TGF-β1, type I collagen, and type III collagen in PEMF-stimulated culture than in controls [28].
1. Fukada E, Yasuda I. On the piezoelectric effect of bone. J Phys Soc Jpn. 1957;12:121–128.
2. Bassett CA, Becker RO. Generation of electric potentials in bone in response to mechanical stress. Science. 1962;137:1063–1064.
3. Xu J, Wang W, Clark CC, Brighton CT. Signal transduction in electrically stimulated articular chondrocytes involves translocation of extracellular calcium through voltage-gated channels. Osteoarthritis Cart. 2009;17(3):397–405.
4. Galvani L. De viribus electricitatis in motu musculari commentarius. Bologna, Italy: Ex typographia. Instituti Scientiarum, 1791.
5. Black J. Electrical Stimulation. New York: Praeger, 1987.
6. Guzelsu N. Piezoelectric and electrokinetic effects in bone tissue. Electro Magnet Biol. 1993;12(1):51–82. Review.
7. Green J, Kleeman CR. Role of bone in regulation of systemic acid-base balance. Kidney Int. 1991;39:9–26.
8. Otter MW, Vincent R, Palmieri VR, Dadong DWu, Seiz KG, Mac Ginitie LA, Cochran GVB. A comparative analysis of streaming potentials in vivo and in vitro. J Orthopaedic Res. 1992;10:710–719.
9. Pollack SR. Bioelectrical properties of bone. Endogenous electrical signals. Orthop Clin North Am.1984;15:3–14.
10. Behari J. Electrostimulation and bone fracture healing. Biomed Eng. 1992;18:235–254.
11. Wolff J. Das Gesetz der Transformation der Knochen. Berlin, Germany: Hirschwald, 1892.
12. Friedenberg ZB, Brighton CT. Bioelectric potentials in bone. J Bone Joint Surg Am. 1966;48(5):915–923.
13. Friedenberg ZB, Dyer R, Brighton CT. Electro-osteograms of long bones of immature rabbits. J Dent Res. 1971;50(3):635–639.
14. Friedenberg ZB, Harlow MC, Heppenstall R, Brighton CT. The cellular origin of bioelectric potentials in bone. Calcif Tissue Res. 1973;13(1):53–62.
15. Rubinacci A, Brigatti L, Tessari L. A reference curve for axial bioelectric potentials in adult rabbit tibia. Bioelectromagnetics. 1984;5(2):193–202.
16. Chakkalakal DA, Wilson RF, Connolly JF. Epidermal and endosteal sources of endogenous electricity in injured canine limbs. IEEE Trans Biomed Eng. 1988;35(1):19–30.
17. Lokietek W, Pawluk RF, Bassett CA. Muscle injury potentials: A source of voltage in the undeformed rabbit tibia. J Bone Joint Surg Br. 1974;56(2):361–369.
18.Borgens RB. Endogenous ionic currents traverse intact and damaged bone. Science.
1984;225(4661):478–482.
19. De Ponti A, Villa I, Boniforti F, Rubinacci A. Ionic currents at the growth plate of intact bone: occurrence and ionic dependence. Electro- Magneto Biol. 1996;15(1):37–48.
20. Rubinacci A, De Ponti A, Shipley A, Samaja M, Karplus E, Jaffe LF. Bicarbonate dependence of ion current in damaged bone. Calcif Tissue Int. 1996;58:423–428.
21. Aaron RK, Boyan BD, Ciombor DM, Schwartz Z, Simon BJ. Stimulation of growth factor synthesis by electric and electromagnetic fields. Clin Orthop Relat Res. 2004;(419):30–37. Review.
22. Brighton CT, Wang W, Seldes R, Zhang G, Pollack SR. Signal transduction in electrically stimulated bone cells. J Bone Joint Surg Am. 2001;83-A(10):1514–1523.
23. Nagai M, Ota M. Pulsating electromagnetic field stimulates mRNA expression of bone morphogenetic protein -2 and -4. J Dental Res. 1994;73:1601–1605.
24. Bodamyali T, Bhatt B, Hughes FJ, Winrow VR, Kanczler JM, Simon B, Abbott J, Blake DR, Stevens CR. Pulsed electromagnetic fields simultaneously induce osteogenesis and upregulate transcription of bone morphogenetic proteins 2 and 4 in rat osteoblasts in vitro. Biochem Biophys Res Commun. 1998;250(2):458–461.
25. Guerkov HH1, Lohmann CH, Liu Y, Dean DD, Simon BJ, Heckman JD, Schwartz Z, Boyan BD. Pulsed electromagnetic fields increase growth factor release by nonunion cells. Clin Orthop Relat Res. 2001;(384):265–279.
26. Aaron RK, Ciombor DM, Keeping H, Wang S, Capuano A, Polk C. Power frequency fields promote cell differentiation coincident with an increase in transforming growth factor-beta(1) expression. Bioelectromagnetics. 1999;20(7):453–458. Erratum in: Bioelectromagnetics. 2000;21(1):73.
27. Lohmann CH, Schwartz Z, Liu Y, Guerkov H, Dean DD, Simon B, Boyan BD. Pulsed electromag- netic field stimulation of MG63 osteoblast-like cells affects differentiation and local factor production. J Orthop Res. 2000;18(4):637–646.
28. Fassina L, Visai L, Benazzo F, Benedetti L, Calligaro A, De Angelis MG, Farina A, Maliardi V, Magenes G. Effects of electromagnetic stimulation on calcified matrix production by SAOS-2 cells over a polyurethane porous scaffold. Tissue Eng. 2006;12(7):1985–1999.
29. Jansen JH, van der Jagt OP, Punt BJ, Verhaar JA, van Leeuwen JP, Weinans H, Jahr H. Stimulation of osteogenic differentiation in human osteoprogenitor cells by pulsed electromagnetic fields: An in vitro study. BMC Musculoskelet Disord. 2010;11:188.
30. Esposito M, Lucariello A, Riccio I, Riccio V, Esposito V, Riccardi G. Differentiation of human osteopro- genitor cells increases after treatment with pulsed electromagnetic fields. In Vivo. 2012;26(2):299–304.
31. Ceccarelli G, Bloise N, Mantelli M, Gastaldi G, Fassina L, De Angelis MG, Ferrari D, Imbriani M, Visai L. A comparative analysis of the in vitro effects of pulsed electromagnetic field treatment on osteo- genic differentiation of two different mesenchymal cell lineages. Biores Open Access. 2013;2(4):283–294.
32. Lim K, Hexiu J, Kim J, Seonwoo H, Cho WJ, Choung PH, Chung JH. Effects of electromagnetic fields on osteogenesis of human alveolar bone-derived mesenchymal stem cells. Biomed Res Int. 2013;2013:296019. doi: 10.1155/2013/296019. Epub 2013 Jun 19.
33. Zhou J, Wang JQ, Ge BF, Ma XN, Ma HP, Xian CJ, Chen KM. Different electromagnetic field wave- forms have different effects on proliferation, differentiation and mineralization of osteoblasts in vitro. Bioelectromagnetics. 2013. doi: 10.1002/bem.21794.
34. Zhuang H, Wang W, Seldes RM, Tahernia AD, Fan H, Brighton CT. Electrical stimulation induces the level of TGF-β1 mRNA in osteoblastic cells by a mechanism involving calcium/calmodulin pathway. Biochem Biophys Res Comm. 1997;237:225–229.
35. Hartig M, Joos U, Wiesmann HP. Capacitively coupled electric fields accelerate proliferation of osteoblast-like primary cells and increase bone extracellular matrix formation in vitro. Eur Biophys J. 2000;29(7):499–506.
36. Wang Z, Clark CC, Brighton CT. Up-regulation of bone morphogenetic proteins in cultured murine bone cells with use of specific electric fields. J Bone Joint Surg Am. 2006;88(5):1053–1065.
37. Bisceglia B, Zirpoli H, Caputo M, Chiadini F, Scaglione A, Tecce MF. Induction of alkaline phosphatase activity by exposure of human cell lines to a low-frequency electric field from apparatuses used in clinical therapies. Bioelectromagnetics. 2011;32(2):113–119.
38. Clark CC, Wang W, Brighton CT. Up-regulation of expression of selected genes in human bone cells with specific capacitively coupled electric fields. J Orthop Res. July 2014; 32(7):894–903.
39. Hauser J, Hauser M, Muhr G, Esenwein S. Ultrasound-induced modifications of cytoskeletal components in osteoblast-like SAOS-2 cells. J Orthop Res. 2009;27(3):286–294.
40. Fassina L, Saino E, De Angelis MG, Magenes G, Benazzo F, Visai L. Low-power ultrasounds as a tool to culture human osteoblasts inside cancellous hydroxyapatite. Bioinorg Chem Appl. 2010:456240. doi: 10.1155/2010/456240. Epub 2010 Mar 31.
41. Xue H, Zheng J, Cui Z et al. Low-intensity pulsed ultrasound accelerates tooth movement via activation of the BMP-2 signaling pathway. PLoS ONE. 2013;8(7):e68926.
42. Aaron RK, Ciombor DM. Acceleration of experimental endochondral ossification by biophysical stimu- lation of the progenitor cell pool. J Orthop Res. 1996;14(4):582–589.
43. Ciombor DM, Aaron RK. The role of electrical stimulation in bone repair. Foot Ankle Clin. 2005;10(4): 579–593. Review.
**Soft Tissue - Currents of Injury and Currents of Healing**
One rationale for EMFT use for soft tissue healing initially derived from its efficacy in bone healing. Subsequent extensions to soft tissue healing have evolved with their own plausible rationales related to the body’s natural bioelectric system [1,2] and from early observed relationships between electrical events and wound repair [3] and naturally occurring 10 μA current loops measured in human legs [4]. Adding to these considerations is the fact that cellular function is largely determined by membrane electrical processes. A dermal wound will interrupt the normal epithelial cell potentials at the injury site causing an injury-related electric field and associated injury currents that are postulated to play an important role in the healing process [5,6]. The injury currents and associated electric fields arise because of the disruption of the normal transepidermal potential (TEP) that is maintained by Na+ and Cl− ion fluxes through their associated channels. In unbroken skin, this results in a TEP between stratum corneum (SC) and the basal layer of the epidermis of 20–50 mV with the SC relatively negative [5]. When a wound is present, the TEP drives currents through the low electrical resistance of the wound, causing a lateral electric field [7], the magnitude of which decreases as the wound heals and which is smaller with advancing age [8,9]. The injury current is reported as less than 1 mA with a lateral electric field of near 200 mV/mm at the wound site, which reduces to 0 at about 2 cm from the wound [10] . The injury current has been measured to be up to 22 nA/cm2 at tips of accidentally amputated fingers in children [11]. Because cells involved in healing are electrically charged, the endogenous bioelectricity facilitates cells to migrate to the wound [12] to help the healing process.
One mechanism for the success of this method is that electric fields can attract cells into the repair field. The surfaces of neutrophils, macrophages, fibroblasts, and epidermal cells involved in wound repair are electrically charged.
An applied electric field can facilitate galvanotaxic migrations of these cells into the repair field and thereby accelerate healing.
Electrotaxis, also known as galvanotaxis, is the directed motion of biological cells or organisms guided by an electric field or current.
EMFT may interact directly with wound currents or with related signal transduction processes [13], thereby restimulating retarded or arrested healing. Alternately, we argue that EMFT may mimic one or more intrinsic bioelectric effects and help trigger renewed healing. Accelerated healing by direct currents (200–800 μA) may be due to such a process [14]. There is more recent evidence to support the notion that applied low- intensity currents in the range of the injury current can enhance wound healing [15]. Another example may be that in which low-level currents of about 40 μA delivered via wearable devices reduced periwound edema from an initial depth of 1.6 mm to about 0.6 mm after 10 days of treatment [16]; however, additional research in this area is needed. Reported benefits of EMFT on cellular and other processes involved in wound repair are manifold and include edema reduction, blood flow changes and cellular proliferation, migration, differentiation, and upregulation of various cell functions as will be discussed subsequently.
[1] Becker RO. Augmentation of regenerative healing in man. A possible alternative to prosthetic implantation. Clin Orthop 83 (1972):255–262.
[2] Nordenstrom BE. Impact of biologically closed electric circuits (BCEC) on structure and function. Integr Physiol Behav Sci 27 (1992):285–303.
[3] Burr HS, Harvey SC, Taffel M. Bio-electric correlates of wound healing. Yale J Biol Med 11 (1938):104–107.
[4] Grimnes S. Pathways of ionic flow through human skin in vivo. Acta Derm Venereol 64 (1984):93–98.
[5] Barker AT, Jaffe LF, Vanable JW, Jr. The glabrous epidermis of cavies contains a powerful battery. Am J Physiol 242 (1982):R358–R366.
[6] Foulds IS, Barker AT. Human skin battery potentials and their possible role in wound healing. Br J Dermatol 109 (1983):515–522.
[7] Nuccitelli R. A role for endogenous electric fields in wound healing. Curr Top Dev Biol 58 (2003):1–26.
[8] Nuccitelli R, Nuccitelli P, Ramlatchan S, Sanger R, Smith PJ. Imaging the electric field associated with mouse
and human skin wounds. Wound Repair Regen 16 (2008):432–441.
[9] Nuccitelli R, Nuccitelli P, Li C, Narsing S, Pariser DM, Lui K. The electric field near human skin wounds declines with age and provides a noninvasive indicator of wound healing. Wound Repair Regen 19 (2011):645–655.
[10] Jaffe LF, Vanable JW, Jr. Electric fields and wound healing. Clin Dermatol 2 (1984):34–44.
[11] Illingworth CM, Barker AT. Measurement of electrical currents emerging during the regeneration of amputated finger tips in children. Clin Phys Physiol Meas 1 (1980):87.
[12] Vanable JW, Jr. (1989) Integumentary potentials and wound healing. In: Electric Fields in Vertebrate Repair, Ed. Borgens RB, pp. 171–224. Alan R. Liss, Inc, New York.
[13] Lee RC, Canaday DJ, Doong H. A review of the biophysical basis for the clinical application of electric fields in soft-tissue repair. J Burn Care Rehabil 14 (1993):319–335.
[14] Carley PJ, Wainapel SF. Electrotherapy for acceleration of wound healing: Low intensity direct current. Arch Phys Med Rehabil 66 (1985):443–446.
[15] Balakatounis KC, Angoules AG. Low-intensity electrical stimulation in wound healing: Review of the efficacy of externally applied currents resembling the current of injury. Eplasty 8 (2008):e28.
[16] Young S, Hampton S, Tadej M. Study to evaluate the effect of low-intensity pulsed electrical currents on levels of oedema in chronic non-healing wounds. J Wound Care 20 (2011):368, 370–363.
One rationale for EMFT use for soft tissue healing initially derived from its efficacy in bone healing. Subsequent extensions to soft tissue healing have evolved with their own plausible rationales related to the body’s natural bioelectric system [1,2] and from early observed relationships between electrical events and wound repair [3] and naturally occurring 10 μA current loops measured in human legs [4]. Adding to these considerations is the fact that cellular function is largely determined by membrane electrical processes. A dermal wound will interrupt the normal epithelial cell potentials at the injury site causing an injury-related electric field and associated injury currents that are postulated to play an important role in the healing process [5,6]. The injury currents and associated electric fields arise because of the disruption of the normal transepidermal potential (TEP) that is maintained by Na+ and Cl− ion fluxes through their associated channels. In unbroken skin, this results in a TEP between stratum corneum (SC) and the basal layer of the epidermis of 20–50 mV with the SC relatively negative [5]. When a wound is present, the TEP drives currents through the low electrical resistance of the wound, causing a lateral electric field [7], the magnitude of which decreases as the wound heals and which is smaller with advancing age [8,9]. The injury current is reported as less than 1 mA with a lateral electric field of near 200 mV/mm at the wound site, which reduces to 0 at about 2 cm from the wound [10] . The injury current has been measured to be up to 22 nA/cm2 at tips of accidentally amputated fingers in children [11]. Because cells involved in healing are electrically charged, the endogenous bioelectricity facilitates cells to migrate to the wound [12] to help the healing process.
One mechanism for the success of this method is that electric fields can attract cells into the repair field. The surfaces of neutrophils, macrophages, fibroblasts, and epidermal cells involved in wound repair are electrically charged.
An applied electric field can facilitate galvanotaxic migrations of these cells into the repair field and thereby accelerate healing.
Electrotaxis, also known as galvanotaxis, is the directed motion of biological cells or organisms guided by an electric field or current.
EMFT may interact directly with wound currents or with related signal transduction processes [13], thereby restimulating retarded or arrested healing. Alternately, we argue that EMFT may mimic one or more intrinsic bioelectric effects and help trigger renewed healing. Accelerated healing by direct currents (200–800 μA) may be due to such a process [14]. There is more recent evidence to support the notion that applied low- intensity currents in the range of the injury current can enhance wound healing [15]. Another example may be that in which low-level currents of about 40 μA delivered via wearable devices reduced periwound edema from an initial depth of 1.6 mm to about 0.6 mm after 10 days of treatment [16]; however, additional research in this area is needed. Reported benefits of EMFT on cellular and other processes involved in wound repair are manifold and include edema reduction, blood flow changes and cellular proliferation, migration, differentiation, and upregulation of various cell functions as will be discussed subsequently.
[1] Becker RO. Augmentation of regenerative healing in man. A possible alternative to prosthetic implantation. Clin Orthop 83 (1972):255–262.
[2] Nordenstrom BE. Impact of biologically closed electric circuits (BCEC) on structure and function. Integr Physiol Behav Sci 27 (1992):285–303.
[3] Burr HS, Harvey SC, Taffel M. Bio-electric correlates of wound healing. Yale J Biol Med 11 (1938):104–107.
[4] Grimnes S. Pathways of ionic flow through human skin in vivo. Acta Derm Venereol 64 (1984):93–98.
[5] Barker AT, Jaffe LF, Vanable JW, Jr. The glabrous epidermis of cavies contains a powerful battery. Am J Physiol 242 (1982):R358–R366.
[6] Foulds IS, Barker AT. Human skin battery potentials and their possible role in wound healing. Br J Dermatol 109 (1983):515–522.
[7] Nuccitelli R. A role for endogenous electric fields in wound healing. Curr Top Dev Biol 58 (2003):1–26.
[8] Nuccitelli R, Nuccitelli P, Ramlatchan S, Sanger R, Smith PJ. Imaging the electric field associated with mouse
and human skin wounds. Wound Repair Regen 16 (2008):432–441.
[9] Nuccitelli R, Nuccitelli P, Li C, Narsing S, Pariser DM, Lui K. The electric field near human skin wounds declines with age and provides a noninvasive indicator of wound healing. Wound Repair Regen 19 (2011):645–655.
[10] Jaffe LF, Vanable JW, Jr. Electric fields and wound healing. Clin Dermatol 2 (1984):34–44.
[11] Illingworth CM, Barker AT. Measurement of electrical currents emerging during the regeneration of amputated finger tips in children. Clin Phys Physiol Meas 1 (1980):87.
[12] Vanable JW, Jr. (1989) Integumentary potentials and wound healing. In: Electric Fields in Vertebrate Repair, Ed. Borgens RB, pp. 171–224. Alan R. Liss, Inc, New York.
[13] Lee RC, Canaday DJ, Doong H. A review of the biophysical basis for the clinical application of electric fields in soft-tissue repair. J Burn Care Rehabil 14 (1993):319–335.
[14] Carley PJ, Wainapel SF. Electrotherapy for acceleration of wound healing: Low intensity direct current. Arch Phys Med Rehabil 66 (1985):443–446.
[15] Balakatounis KC, Angoules AG. Low-intensity electrical stimulation in wound healing: Review of the efficacy of externally applied currents resembling the current of injury. Eplasty 8 (2008):e28.
[16] Young S, Hampton S, Tadej M. Study to evaluate the effect of low-intensity pulsed electrical currents on levels of oedema in chronic non-healing wounds. J Wound Care 20 (2011):368, 370–363.
Non-Depolarizing Electromagnetic Fields
With the advent of inductive stimulation methods came the study of the effects of non-depolarizing electromagnetic fields on tissues other than bone. Non-depolarizing electric fields are those which are too low to induce overt depolarization of the cell membrane as in the case of an action potential, but strong enough to presumably have other effects on molecular mechanisms within cells and in the extracellular space.
With the advent of inductive stimulation methods came the study of the effects of non-depolarizing electromagnetic fields on tissues other than bone. Non-depolarizing electric fields are those which are too low to induce overt depolarization of the cell membrane as in the case of an action potential, but strong enough to presumably have other effects on molecular mechanisms within cells and in the extracellular space.
Types of biologically relevant signals
There are three key levels of signals that need to be specified in order to properly define the waveform parameters that are to be used when inductively stimulating:
1) Current flowing into the coils from the stimulation unit. This is the original driving signal that is produced by the electronic circuit within the PEMF device to drive the coil that will then produce the magnetic field.
==> The induction of electrical fields within tissues requires magnetic fields that vary in time, and typically this is accomplished using a computer or a microcontroller-based platform to drive current waveforms through solenoid coils. To induce the desired electrical fields it is essential to control the slew-rate (rate of change or first time derivative of the magnetic flux) of the signal. Thus, it is of utmost importance that the primary driving electronics have adequate dynamic performance.
2) The time-varying magnetic flux in and around the coils resulting from the electrical current driving the wire coils.
==> Faraday’s law of induction shows that the induced circular electric field in a conducting surface is proportional to the inverse of the rate of change of the magnetic flux (defined as the magnetic field strength times the area through which it is passing). The key parameters involved with the induced electric field are the rate of change of the magnetic field (i.e. dB/dt, which is the first time derivative of the magnetic flux B) and the radius around which one examines the field of interest. Specifically, the larger the rate of change of the magnetic field, the larger the possible induced electric field. Maxwell’s relationship explains why the driving electronics must have good dynamic performance: to provide adequate magnetic flux slew rate to induce the desired electric field in the tissue. For a given magnetic flux change, the larger the radius of interest (up to the inner radius of the stimulating coil), the larger the induced field, and the smaller the radius, the smaller the induced field.
For the most part, the second level signal—magnetic flux—is the most relevant signal to specify because it is prone to deviate from theoretical values when calculated based upon the presumed driver circuit performance, it is readily measured using modern analog signal Hall effect sensors, and when measured accurately yields good estimates of the induced field within the tissues
There are three key levels of signals that need to be specified in order to properly define the waveform parameters that are to be used when inductively stimulating:
1) Current flowing into the coils from the stimulation unit. This is the original driving signal that is produced by the electronic circuit within the PEMF device to drive the coil that will then produce the magnetic field.
==> The induction of electrical fields within tissues requires magnetic fields that vary in time, and typically this is accomplished using a computer or a microcontroller-based platform to drive current waveforms through solenoid coils. To induce the desired electrical fields it is essential to control the slew-rate (rate of change or first time derivative of the magnetic flux) of the signal. Thus, it is of utmost importance that the primary driving electronics have adequate dynamic performance.
2) The time-varying magnetic flux in and around the coils resulting from the electrical current driving the wire coils.
==> Faraday’s law of induction shows that the induced circular electric field in a conducting surface is proportional to the inverse of the rate of change of the magnetic flux (defined as the magnetic field strength times the area through which it is passing). The key parameters involved with the induced electric field are the rate of change of the magnetic field (i.e. dB/dt, which is the first time derivative of the magnetic flux B) and the radius around which one examines the field of interest. Specifically, the larger the rate of change of the magnetic field, the larger the possible induced electric field. Maxwell’s relationship explains why the driving electronics must have good dynamic performance: to provide adequate magnetic flux slew rate to induce the desired electric field in the tissue. For a given magnetic flux change, the larger the radius of interest (up to the inner radius of the stimulating coil), the larger the induced field, and the smaller the radius, the smaller the induced field.
For the most part, the second level signal—magnetic flux—is the most relevant signal to specify because it is prone to deviate from theoretical values when calculated based upon the presumed driver circuit performance, it is readily measured using modern analog signal Hall effect sensors, and when measured accurately yields good estimates of the induced field within the tissues
3) The induced electric field in the tissue volume resulting from the time-varying magnetic flux generated by the coils.
Thirdly, it is necessary to discuss the induced electric field—specifically with regard to the tissue volumes of interest. The induced field can be calculated using the equation shown here**.
Schaefer, D.J., Bourland, J.D. and Nyenhuis, J.A. (2000), Review of Patient Safety in Time-Varying Gradient Fields. J. Magn. Reson. Imaging, 12: 20-29. .
In the case of eddy currents within a tissue, one can consider the conducting pathways to be represented by the fluid in the pericellular space, just outside the cell membrane and between cells and thus, circular pathways around cells are those of interest.
If one considers thermal noise averaging, and cellular response, then the predicted threshold induced field for a measureable response is on the order of 10^-3 – 10^-5 V/m*
Weaver JC, Astumian RD. The response of living cells to very weak electric fields: the thermal noise limit. Science. 1990 Jan 26;247(4941):459-62
Assuming the low-end of the stimulation threshold to be approximately 10-5 V/m, the smallest signal that one might expect to use and still observe a physiological response is approximately 4 T/s.
Area of Usefulness ==> at least 4 T/s
I've been doing a lot of calculations, and if the ideal rise time is between 5t/s and 30 t/s, then a coil design that keeps that range is fairly difficult to design. Next to the coil there will be a rise time faster than 30t/s and 8" away the rise time will be below 2t/s. This makes every coil have an "area of usefulness" where the rise time is between the two extremes (this is obviously something where more research would be helpful). It almost make sense to make the "area of usefulness" tunable so that people can set it close to the coil for surface wounds, and far from the coil for deeper treatments
==> The best coil design will spread the rate of change out as evenly as possible
Large Coil
Capacitive Layer
Right Signal
Inductance
Radius
Current
Voltage
Resistance
Inner winding capacitance
Pulse Duration
Thirdly, it is necessary to discuss the induced electric field—specifically with regard to the tissue volumes of interest. The induced field can be calculated using the equation shown here**.
Schaefer, D.J., Bourland, J.D. and Nyenhuis, J.A. (2000), Review of Patient Safety in Time-Varying Gradient Fields. J. Magn. Reson. Imaging, 12: 20-29. .
In the case of eddy currents within a tissue, one can consider the conducting pathways to be represented by the fluid in the pericellular space, just outside the cell membrane and between cells and thus, circular pathways around cells are those of interest.
If one considers thermal noise averaging, and cellular response, then the predicted threshold induced field for a measureable response is on the order of 10^-3 – 10^-5 V/m*
Weaver JC, Astumian RD. The response of living cells to very weak electric fields: the thermal noise limit. Science. 1990 Jan 26;247(4941):459-62
Assuming the low-end of the stimulation threshold to be approximately 10-5 V/m, the smallest signal that one might expect to use and still observe a physiological response is approximately 4 T/s.
Area of Usefulness ==> at least 4 T/s
I've been doing a lot of calculations, and if the ideal rise time is between 5t/s and 30 t/s, then a coil design that keeps that range is fairly difficult to design. Next to the coil there will be a rise time faster than 30t/s and 8" away the rise time will be below 2t/s. This makes every coil have an "area of usefulness" where the rise time is between the two extremes (this is obviously something where more research would be helpful). It almost make sense to make the "area of usefulness" tunable so that people can set it close to the coil for surface wounds, and far from the coil for deeper treatments
==> The best coil design will spread the rate of change out as evenly as possible
Large Coil
Capacitive Layer
Right Signal
Inductance
Radius
Current
Voltage
Resistance
Inner winding capacitance
Pulse Duration
***Case Short Ramp Duration***
Note that for short ramp durations, mean nerve stimulation thresholds expressed in dB/dt can become large. However, the safety margin between nerve stimulation and cardiac stimulation increases as ramp duration is reduced.
Note that for short ramp durations, mean nerve stimulation thresholds expressed in dB/dt can become large. However, the safety margin between nerve stimulation and cardiac stimulation increases as ramp duration is reduced.
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Formica, Domenico & Silvestri, Sergio. (2004). Biological effects of exposure to magnetic resonance imaging: An overview. Biomedical engineering online. 3. 11. 10.1186/1475-925X-3-11.
IEC. Particular requirements for the safety of magnetic resonance equipment for medical diagnosis. In: Diagnostic imaging equipment, publication IEC 60601-2-33, medical electrical equipment, Part 2. International Electrotechnology Commission, International Electrotechnical Commission (IEC), 3, rue de Varembé, P.O. Box 131, CH-1211 Geneva 20, Switzerland, 1995.
IEC. Particular requirements for the safety of magnetic resonance equipment for medical diagnosis. In: Diagnostic imaging equipment, publication IEC 60601-2-33, medical electrical equipment, Part 2. International Electrotechnology Commission, International Electrotechnical Commission (IEC), 3, rue de Varembé, P.O. Box 131, CH-1211 Geneva 20, Switzerland, 1995.
Note on Slew Rate vs Resonance
Therefore many Slew rate PEMF technologies do not take advantage of the inherent natural mechanisms of biological signal amplification, preferring instead to use a brute-force approach to coerce the target tissue toward the desired response rather than employing high fidelity signals that work with innate biological filters and amplifiers
Therefore many Slew rate PEMF technologies do not take advantage of the inherent natural mechanisms of biological signal amplification, preferring instead to use a brute-force approach to coerce the target tissue toward the desired response rather than employing high fidelity signals that work with innate biological filters and amplifiers
Figure 4.Representative ICES waveforms. A.) Sinusoidal waveforms have smoothly varying edges, and can also be pulsed at high frequencies to produce PRF signals. B.) Trapezoidal and square waveforms represent waveforms with large rising and falling edge slopes and non-changing peaks and troughs. C.) Asymmetric pulses, such as the saw-tooth waveform shown, represent waveforms that have large rising and/or falling edge slopes, but provide non-symmetric induced electric fields within tissues of interest. A description of the numbered portions above can be found in Table 1..
Trapezoidal and triangular magnetic pulses can be generated individually with long periods of inactivity between pulses, but it is possible by this approach to generate very large induced electric fields by driving the trapezoidal waveforms with very steep rising and falling edges, that is, incorporating large slew rates to each edge of each trapezoidal or triangular pulse. Such signals are easily capable of producing 1.5 V/m induced signals while keeping peak magnetic field strength well below 0.1 T provided the pulse can be delivered in a short enough time (approximately 100 µs).
Frequency modulated signals provide an alternative method for producing high slew-rate signals by encoding low frequency signals in high frequency (1-27.12 MHz) sinusoidal carrier waves.
Demodulation allows these high frequency bursts to have brain entrainment effects.
Trapezoidal and triangular magnetic pulses can be generated individually with long periods of inactivity between pulses, but it is possible by this approach to generate very large induced electric fields by driving the trapezoidal waveforms with very steep rising and falling edges, that is, incorporating large slew rates to each edge of each trapezoidal or triangular pulse. Such signals are easily capable of producing 1.5 V/m induced signals while keeping peak magnetic field strength well below 0.1 T provided the pulse can be delivered in a short enough time (approximately 100 µs).
Frequency modulated signals provide an alternative method for producing high slew-rate signals by encoding low frequency signals in high frequency (1-27.12 MHz) sinusoidal carrier waves.
Demodulation allows these high frequency bursts to have brain entrainment effects.
**SLEW RATE STUDIES**
Orthofix Physiostim CLASSIC vs HSR (High Slew Rate)
1) A comparison of alendronate to varying magnitude PEMF in mitigating bone loss and altering bone remodeling in skeletally mature osteoporotic rats
***High Slew Rate - Burst - but not too high (30 - 100 ideal dose response)
https://www.sciencedirect.com/science/article/abs/pii/S8756328220305494
http://scalarsymphony.health/articles-pemf/A%20comparison%20of%20alendronate%20to%20varying%20magnitude%20PEMF%20in%20mitigating%20bone%20loss%20and%20altering%20bone%20remodeling%20in%20skeletally%20mature%20osteoporotic%20rats.pdf
Trabecular bone, is porous bone composed of trabeculated bone tissue. It can be found at the ends of long bones like the femur, where the bone is actually not solid but is full of holes connected by thin rods and plates of bone tissue.
3.85 kHz as equal to the fundamental frequency of the quasi-rectangular waveform of the commercial device (Physio-Stim™, which the study was designed to emulate) and four discrete B field magnitudes of 0.41 mT, 1.2 mT, 4.1 mT and 12.4 mT, corresponding to dB/dt field magnitudes of 10 T/s (characteristic of Physio-Stim™), 30 T/s, 100 T/s and 300 T/s respectively
The observed PEMF dose dependency in tested outcomes was not a simple relationship; rather there appeared to be a range of PEMF slew rate that provided better bone outcomes than others. In this study, the middle range of PEMF slew rate of 30–100 T/s (having similar 3850 Hz frequency sinusoids in bursts of 15 Hz) more effectively reduced trabecular bone loss in OVX rats than PEMF treatments with higher or lower slew rates.
1) A comparison of alendronate to varying magnitude PEMF in mitigating bone loss and altering bone remodeling in skeletally mature osteoporotic rats
***High Slew Rate - Burst - but not too high (30 - 100 ideal dose response)
https://www.sciencedirect.com/science/article/abs/pii/S8756328220305494
http://scalarsymphony.health/articles-pemf/A%20comparison%20of%20alendronate%20to%20varying%20magnitude%20PEMF%20in%20mitigating%20bone%20loss%20and%20altering%20bone%20remodeling%20in%20skeletally%20mature%20osteoporotic%20rats.pdf
Trabecular bone, is porous bone composed of trabeculated bone tissue. It can be found at the ends of long bones like the femur, where the bone is actually not solid but is full of holes connected by thin rods and plates of bone tissue.
3.85 kHz as equal to the fundamental frequency of the quasi-rectangular waveform of the commercial device (Physio-Stim™, which the study was designed to emulate) and four discrete B field magnitudes of 0.41 mT, 1.2 mT, 4.1 mT and 12.4 mT, corresponding to dB/dt field magnitudes of 10 T/s (characteristic of Physio-Stim™), 30 T/s, 100 T/s and 300 T/s respectively
The observed PEMF dose dependency in tested outcomes was not a simple relationship; rather there appeared to be a range of PEMF slew rate that provided better bone outcomes than others. In this study, the middle range of PEMF slew rate of 30–100 T/s (having similar 3850 Hz frequency sinusoids in bursts of 15 Hz) more effectively reduced trabecular bone loss in OVX rats than PEMF treatments with higher or lower slew rates.
HSR - High Slew Rate 30 T/s > 10 T/s
2) Pulsed Electromagnetic Field Enhances Healing of a Meniscal Tear and Mitigates Posttraumatic Osteoarthritis in a Rat Model
https://www.researchgate.net/publication/362008725_Pulsed_Electromagnetic_Field_Enhances_Healing_of_a_Meniscal_Tear_and_Mitigates_Posttraumatic_Osteoarthritis_in_a_Rat_Model/link/62d3be92d351bd24f51e8c58/download
Among the 3 groups, HSR PEMF treatment demonstrated stronger anti-inflammatory effects by significantly downregulating the secretion levels of IL-1b and TNF-a in the synovium and meniscus.
In contrast to classic PEMF treatment (three hrs/day), HSR PEMF treatment (one hr/day) achieved similar
promoting effects on bone formation.
30 T/s > 10 T/s
Slew rate is defined as the rate of B-field change over time and calculated per the following equation: slew rate = dB/dt. The classic signal has been approved by the FDA to manage long bone nonunions. 15 The HSR signal has the same pulse and burst frequencies as the classic signal but with a higher slew rate. Namely, the HSR signal could deliver a greater amount of energy per unit time.
3) High slew rate pulsed electromagnetic field enhances bone consolidation and shortens daily treatment duration in distraction osteogenesis
30 T/s> 10 T/s
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8696558/
By comparison, the HSR signal (three hrs/day) treatment group achieved the best healing outcome, in that endochondral ossification and bone consolidation were enhanced. In addition, HSR signal treatment (one one hr/day) had similar effects to treatment using the classic signal (three three hrs/day), indicating that treatment duration could be significantly shortened with the HSR signal.
https://boneandjoint.org.uk/Article/10.1302/2046-3758.1012.BJR-2021-0274.R1/pdf
4) A novel pulsed electromagnetic field promotes distraction osteogenesis via enhancing osteogenesis and angiogenesis in a rat model 30 >10 T/s
https://www.researchgate.net/publication/346483744_A_novel_pulsed_electromagnetic_field_promotes_distraction_osteogenesis_via_enhancing_osteogenesis_and_angiogenesis_in_a_rat_model
Our study showed that new high slew rate PEMF signal could promote osteogenesis and angiogenesis in a rat model of DO, which provides insight into the development of new noninvasive mean to accelerate bone formation in the DO process.
5) 18.8 T/s Slew Rate for Microcirculation
https://onlinelibrary.wiley.com/doi/epdf/10.1016/S0736-0266%2803%2900157-8
2) Pulsed Electromagnetic Field Enhances Healing of a Meniscal Tear and Mitigates Posttraumatic Osteoarthritis in a Rat Model
https://www.researchgate.net/publication/362008725_Pulsed_Electromagnetic_Field_Enhances_Healing_of_a_Meniscal_Tear_and_Mitigates_Posttraumatic_Osteoarthritis_in_a_Rat_Model/link/62d3be92d351bd24f51e8c58/download
Among the 3 groups, HSR PEMF treatment demonstrated stronger anti-inflammatory effects by significantly downregulating the secretion levels of IL-1b and TNF-a in the synovium and meniscus.
In contrast to classic PEMF treatment (three hrs/day), HSR PEMF treatment (one hr/day) achieved similar
promoting effects on bone formation.
30 T/s > 10 T/s
Slew rate is defined as the rate of B-field change over time and calculated per the following equation: slew rate = dB/dt. The classic signal has been approved by the FDA to manage long bone nonunions. 15 The HSR signal has the same pulse and burst frequencies as the classic signal but with a higher slew rate. Namely, the HSR signal could deliver a greater amount of energy per unit time.
3) High slew rate pulsed electromagnetic field enhances bone consolidation and shortens daily treatment duration in distraction osteogenesis
30 T/s> 10 T/s
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8696558/
By comparison, the HSR signal (three hrs/day) treatment group achieved the best healing outcome, in that endochondral ossification and bone consolidation were enhanced. In addition, HSR signal treatment (one one hr/day) had similar effects to treatment using the classic signal (three three hrs/day), indicating that treatment duration could be significantly shortened with the HSR signal.
https://boneandjoint.org.uk/Article/10.1302/2046-3758.1012.BJR-2021-0274.R1/pdf
4) A novel pulsed electromagnetic field promotes distraction osteogenesis via enhancing osteogenesis and angiogenesis in a rat model 30 >10 T/s
https://www.researchgate.net/publication/346483744_A_novel_pulsed_electromagnetic_field_promotes_distraction_osteogenesis_via_enhancing_osteogenesis_and_angiogenesis_in_a_rat_model
Our study showed that new high slew rate PEMF signal could promote osteogenesis and angiogenesis in a rat model of DO, which provides insight into the development of new noninvasive mean to accelerate bone formation in the DO process.
5) 18.8 T/s Slew Rate for Microcirculation
https://onlinelibrary.wiley.com/doi/epdf/10.1016/S0736-0266%2803%2900157-8
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Pulse in Bob Dennis Rabbit Bone Study
Narrow “square” electrical pulses from the PEMF pulse generator circuit yielded skewed triangular magnetic waveforms, as shown. This magnetic waveform is typical, resulting from a 100 micro-second current pulse applied to the PEMF coil in a short cuff, and measured using an analog Hall effect sensor. Note that the rise time corresponds to the electrical current pulse applied the coils (0 μs to 100 μs), while the fall-off time occurs while the coil current drains to ground potential 
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Magnetic Magic
Here is the typical Magnetic Magic pulse. It is 1mT per division up and down and 100uS per division left to right. The curved rise and fall are part of what makes the pulse have good spectral content. You can also see that if the line was straight instead of curved it would be closer to 50 T/s. So technically a portion of the pulse is around 50 T/s but averaged out it is 30 T/s 
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HIGH SLEW RATE PULSE
Robert Dennis Paper - Part 1
https://www.researchgate.net/publication/340330953_Inductively_Coupled_Electrical_Stimulation_-_Part_I_Overview_and_First_Observations
Dennis Robert. Inductively Coupled Electrical Stimulation - Part I: Overview and First Observations. The Journal of Science and Medicine. 2019; 1
***Another study that mentions slew rate - Part 2
BOB DENNIS RABBIT STUDY-- Conclusion
The key parameter for biological effectiveness of PEMF was determined to be magnetic slew rate (dB/dt), and the minimum threshold of this parameter for clinical effectiveness for regeneration of bone tissue after orthopedic injury was found to be ~ 100 kG/s (10 T/s). This magnetic slew rate, when sustained for 100 μs at a pulse rate of 10 Hz, was found to be effective both for pain reduction as well as to induce bone regeneration in a critical defect gap
https://www.josam.org/josam/article/view/27/25#:~:text=The%20optimal%20magnetic%20waveform%20slew,%3D%3E%20100%20kG%2Fs
Dennis Robert. Inductively Coupled Electrical Stimulation - Part 2: Optimization of parameters for orthopedic injuries and pain. The Journal of Science and Medicine. 2020; 1
Robert Dennis Paper - Part 3
https://www.josam.org/josam/article/view/46
Dennis Robert. Inductively Coupled Electrical Stimulation - Part 3: PEMF Systems for use in Basic Research with Laboratory Animals and In Vitro. The Journal of Science and Medicine. 2020; 2
Robert Dennis Paper - Part 4
https://www.josam.org/josam/article/view/58
Dennis Robert, Tommerdahl Anna, Dennis Andromeda. Inductively Coupled Electrical Stimulation - Part 4: Effect of PEMF on seed germination; evidence of triphasic inverse hormesis. The Journal of Science and Medicine. 2021; 2
Robert Dennis Paper - Part 5
https://www.josam.org/josam/article/view/67
Dennis R. (2021). Inductively Coupled Electrical Stimulation - Part 5: How many types of PEMF are there? A model and Excel Calculator; 4(2):1-10.
Robert Dennis Paper - Part 6
https://www.josam.org/josam/article/view/86
Summarizing the results listed it sounds like rise times of 30t/s are more effective than 100t/s, and 10T/s ia better than 5T/s
Robert Dennis Slew Rate and Inflammation 40, 80, 120, 160 then Plateau - 160 and 120 performed sligthly better than 40 (120-160 Ideal)
https://www.josam.org/josam/article/view/38
Both studies indicate rise time (dB/dt) as a critical determinant of efficacy, a characteristic not previously cited in a literature dominated by field strength, frequency, and duration.
** Full Article Here is a paper that says the Nasa PEMF Studies showed that high rise time is critical:
https://onlinelibrary.wiley.com/doi/full/10.1002/jcp.21025
https://onlinelibrary.wiley.com/doi/full/10.1002/jcp.21025
Here is the specific quote "Of relevance, it has been recently shown that applied low-frequency magnetic fields in the range of 1 mT are capable of radical-pair amplification generated by flavin-tryptophan moieties, whereas amplitudes exceeding the hyperfine nuclear interactions limit (∼3 mT) are inefficient at doing so (62), perhaps giving insight as to the origin of the myogenic efficacy amplitude ceiling of the pulsing magnetic fields described in this report (Supplemental Fig. S3)"
Another Study with Slew Rate Windows
https://www.tandfonline.com/doi/abs/10.1080/15368378.2019.1608233
9.5 T/s Successful
https://openurl.ebsco.com/EPDB%3Agcd%3A12%3A11965132/detailv2?sid=ebsco%3Aplink%3Ascholar&id=ebsco%3Agcd%3A15247064&crl=c
Full article not found
Proof 15 T/s works
https://onlinelibrary.wiley.com/doi/full/10.1002/jor.23333
Pulsed electromagnetic field therapy improves tendon-to-bone healing in a rat rotator cuff repair model
Overall, results suggest that PEMF improves early tendon-to-bone healing specifically through an improvement of tendon mechanical properties. We speculate that PEMF treatment may increase tendon cell metabolism, in turn increasing matrix production and collagen remodeling, reflected in improved mechanical properties and increased collagen alignment. A small rotator cuff repair clinical trial utilizing a different PEMF signal demonstrated early increases in range of motion and functional scores.14 Our findings provide further evidence of improvements in mechanical properties and matrix organization, supporting further investigation into clinical use of this therapy for various PEMF waveforms.
17 T/s works
https://www.nature.com/articles/s41598-017-09892-w
15 Hz and at flux densities between 1–4 mT. Each 6 ms burst consisted of a series of 20 consecutive asymmetric pulses of 150 µs on and off duration with an approximate rise time of 17 T/s.
Pulse electromagnetic fields (PEMFs) have been shown to recruit calcium-signaling cascades common to chondrogenesis.
Chondrogenesis is the biological process through which cartilage tissue is formed and developed.
Another proof 17T/s is effective
https://www.sciencedirect.com/science/article/pii/S0142961222002988
17T/s is effective again
https://stemcellres.biomedcentral.com/articles/10.1186/s13287-020-1566-5
We provide evidence that brief exposure to low amplitude PEMFs enhanced the ability of MSCs to produce and secrete paracrine factors capable of promoting cartilage regeneration as well as protecting against adverse inflammatory conditions.
5.3 T/s Worked
https://www.researchgate.net/publication/352001966_Enhancement_of_Nerve_Regeneration_by_Selected_Electromagnetic_Signals
Study showing 2.5 T/s not working
Study showing 1.5 T/s not working
Study showing low slew rate not working
https://www.sciencedirect.com/science/article/abs/pii/S0031938417303876
3mT limit ?
This article makes it look like I should limit the field strength to under 3mt for maximum effectiveness. Have you heard that before?
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6902701/
Pulsed therapeutic fields are usually more effective if less than 30 gauss (see Curie's Law and dipole saturation), and frequencies are commonly less than 100 Hz, below which they are referred to as extremely low frequency (ELF). Cell phones are several magnitudes of order larger in both considerations.
**slew rate causes damage
https://ieeexplore.ieee.org/abstract/document/4062729
**Too much slew rate makes permeable
https://www.researchgate.net/figure/The-waveform-of-the-high-dB-dt-magnetic-field-pulse-Each-magnetic-pulse-was-15-s-wide%C2%A7fig1%C2%A7316490221
Too high of a Slew Rate causes potential unhealthy PNS (Peripheral Nerve Stimulation)
https://onlinelibrary.wiley.com/doi/epdf/10.1002/cmr.10011
***Cells Can Die - Killing Yeast Cells***
Inducing 190 V/cm - 19,000 V/m - Muscle Twitch Induced.
Here is another that specifically mentions dB/dT:
https://pubmed.ncbi.nlm.nih.gov/28238117/
Horse continues to twitch after.
Robert Dennis Paper - Part 1
https://www.researchgate.net/publication/340330953_Inductively_Coupled_Electrical_Stimulation_-_Part_I_Overview_and_First_Observations
Dennis Robert. Inductively Coupled Electrical Stimulation - Part I: Overview and First Observations. The Journal of Science and Medicine. 2019; 1
***Another study that mentions slew rate - Part 2
BOB DENNIS RABBIT STUDY-- Conclusion
The key parameter for biological effectiveness of PEMF was determined to be magnetic slew rate (dB/dt), and the minimum threshold of this parameter for clinical effectiveness for regeneration of bone tissue after orthopedic injury was found to be ~ 100 kG/s (10 T/s). This magnetic slew rate, when sustained for 100 μs at a pulse rate of 10 Hz, was found to be effective both for pain reduction as well as to induce bone regeneration in a critical defect gap
https://www.josam.org/josam/article/view/27/25#:~:text=The%20optimal%20magnetic%20waveform%20slew,%3D%3E%20100%20kG%2Fs
Dennis Robert. Inductively Coupled Electrical Stimulation - Part 2: Optimization of parameters for orthopedic injuries and pain. The Journal of Science and Medicine. 2020; 1
Robert Dennis Paper - Part 3
https://www.josam.org/josam/article/view/46
Dennis Robert. Inductively Coupled Electrical Stimulation - Part 3: PEMF Systems for use in Basic Research with Laboratory Animals and In Vitro. The Journal of Science and Medicine. 2020; 2
Robert Dennis Paper - Part 4
https://www.josam.org/josam/article/view/58
Dennis Robert, Tommerdahl Anna, Dennis Andromeda. Inductively Coupled Electrical Stimulation - Part 4: Effect of PEMF on seed germination; evidence of triphasic inverse hormesis. The Journal of Science and Medicine. 2021; 2
Robert Dennis Paper - Part 5
https://www.josam.org/josam/article/view/67
Dennis R. (2021). Inductively Coupled Electrical Stimulation - Part 5: How many types of PEMF are there? A model and Excel Calculator; 4(2):1-10.
Robert Dennis Paper - Part 6
https://www.josam.org/josam/article/view/86
Summarizing the results listed it sounds like rise times of 30t/s are more effective than 100t/s, and 10T/s ia better than 5T/s
Robert Dennis Slew Rate and Inflammation 40, 80, 120, 160 then Plateau - 160 and 120 performed sligthly better than 40 (120-160 Ideal)
https://www.josam.org/josam/article/view/38
Both studies indicate rise time (dB/dt) as a critical determinant of efficacy, a characteristic not previously cited in a literature dominated by field strength, frequency, and duration.
** Full Article Here is a paper that says the Nasa PEMF Studies showed that high rise time is critical:
https://onlinelibrary.wiley.com/doi/full/10.1002/jcp.21025
https://onlinelibrary.wiley.com/doi/full/10.1002/jcp.21025
Here is the specific quote "Of relevance, it has been recently shown that applied low-frequency magnetic fields in the range of 1 mT are capable of radical-pair amplification generated by flavin-tryptophan moieties, whereas amplitudes exceeding the hyperfine nuclear interactions limit (∼3 mT) are inefficient at doing so (62), perhaps giving insight as to the origin of the myogenic efficacy amplitude ceiling of the pulsing magnetic fields described in this report (Supplemental Fig. S3)"
Another Study with Slew Rate Windows
https://www.tandfonline.com/doi/abs/10.1080/15368378.2019.1608233
9.5 T/s Successful
https://openurl.ebsco.com/EPDB%3Agcd%3A12%3A11965132/detailv2?sid=ebsco%3Aplink%3Ascholar&id=ebsco%3Agcd%3A15247064&crl=c
Full article not found
Proof 15 T/s works
https://onlinelibrary.wiley.com/doi/full/10.1002/jor.23333
Pulsed electromagnetic field therapy improves tendon-to-bone healing in a rat rotator cuff repair model
Overall, results suggest that PEMF improves early tendon-to-bone healing specifically through an improvement of tendon mechanical properties. We speculate that PEMF treatment may increase tendon cell metabolism, in turn increasing matrix production and collagen remodeling, reflected in improved mechanical properties and increased collagen alignment. A small rotator cuff repair clinical trial utilizing a different PEMF signal demonstrated early increases in range of motion and functional scores.14 Our findings provide further evidence of improvements in mechanical properties and matrix organization, supporting further investigation into clinical use of this therapy for various PEMF waveforms.
17 T/s works
https://www.nature.com/articles/s41598-017-09892-w
15 Hz and at flux densities between 1–4 mT. Each 6 ms burst consisted of a series of 20 consecutive asymmetric pulses of 150 µs on and off duration with an approximate rise time of 17 T/s.
Pulse electromagnetic fields (PEMFs) have been shown to recruit calcium-signaling cascades common to chondrogenesis.
Chondrogenesis is the biological process through which cartilage tissue is formed and developed.
Another proof 17T/s is effective
https://www.sciencedirect.com/science/article/pii/S0142961222002988
17T/s is effective again
https://stemcellres.biomedcentral.com/articles/10.1186/s13287-020-1566-5
We provide evidence that brief exposure to low amplitude PEMFs enhanced the ability of MSCs to produce and secrete paracrine factors capable of promoting cartilage regeneration as well as protecting against adverse inflammatory conditions.
5.3 T/s Worked
https://www.researchgate.net/publication/352001966_Enhancement_of_Nerve_Regeneration_by_Selected_Electromagnetic_Signals
Study showing 2.5 T/s not working
Study showing 1.5 T/s not working
Study showing low slew rate not working
https://www.sciencedirect.com/science/article/abs/pii/S0031938417303876
3mT limit ?
This article makes it look like I should limit the field strength to under 3mt for maximum effectiveness. Have you heard that before?
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6902701/
Pulsed therapeutic fields are usually more effective if less than 30 gauss (see Curie's Law and dipole saturation), and frequencies are commonly less than 100 Hz, below which they are referred to as extremely low frequency (ELF). Cell phones are several magnitudes of order larger in both considerations.
**slew rate causes damage
https://ieeexplore.ieee.org/abstract/document/4062729
**Too much slew rate makes permeable
https://www.researchgate.net/figure/The-waveform-of-the-high-dB-dt-magnetic-field-pulse-Each-magnetic-pulse-was-15-s-wide%C2%A7fig1%C2%A7316490221
Too high of a Slew Rate causes potential unhealthy PNS (Peripheral Nerve Stimulation)
https://onlinelibrary.wiley.com/doi/epdf/10.1002/cmr.10011
***Cells Can Die - Killing Yeast Cells***
Inducing 190 V/cm - 19,000 V/m - Muscle Twitch Induced.
Here is another that specifically mentions dB/dT:
https://pubmed.ncbi.nlm.nih.gov/28238117/
Horse continues to twitch after.
NASA Study Showing Squarewave most Biologically Active Waveform
Cell Culture studies: Normal Human Neuronal Progenitor (NHNP) cells were cultured as described in the NASA 2003 paper (3). Briefly, cells were cultured in 100 mm Petri dishes in a temperature, CO2 and humidity controlled cell culture incubator. In initial experiments, not reported in the NASA study, the effects of all 5 waveforms were observed to test the hypothesis that some waveforms would have greater biological effects than others. At that time, detailed gene chip analysis was too costly to perform on every experimental condition, so visual analysis of cell colony formation and density were initially used to rank the effectiveness of each waveform. Both macroscopic and microscopic observations were taken.
https://www.researchgate.net/publication/340330953_Inductively_Coupled_Electrical_Stimulation_-_Part_I_Overview_and_First_Observations
Cell Culture studies: Normal Human Neuronal Progenitor (NHNP) cells were cultured as described in the NASA 2003 paper (3). Briefly, cells were cultured in 100 mm Petri dishes in a temperature, CO2 and humidity controlled cell culture incubator. In initial experiments, not reported in the NASA study, the effects of all 5 waveforms were observed to test the hypothesis that some waveforms would have greater biological effects than others. At that time, detailed gene chip analysis was too costly to perform on every experimental condition, so visual analysis of cell colony formation and density were initially used to rank the effectiveness of each waveform. Both macroscopic and microscopic observations were taken.
https://www.researchgate.net/publication/340330953_Inductively_Coupled_Electrical_Stimulation_-_Part_I_Overview_and_First_Observations
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This one mentions t/s In a few places including a line where it says that 20T/s is the threshold for neuromuscular stimulation
5.3 T/s worked
90 T/s showing a result
2.5 T/s no statisical Significance
1.5 T/s didn't work
Another study showing slew rate is critical
**High slew rate permiability**
Even Dr Pawluk Admits Slew Rate is Important (see video clip below)
Here is clear research showing that the db/dt is directly connected to the induced voltage in your body:
https://www.researchgate.net/figure/Distribution-of-the-induced-electric-field-during-highest-dB-dt-of-the-5-5-coil_fig3_277683544
https://www.researchgate.net/figure/Distribution-of-the-induced-electric-field-during-highest-dB-dt-of-the-5-5-coil_fig3_277683544
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This is one of the reasons I'm leary of kilohertz or megahertz carrier waves for PEMF. Low frequency electrical stimulation of nerves has a regenerative effect, whereas high frequency can make nerve damage worse
13 and 27 Mhz Avoiding Higher Frequency Carrier Waves? This is one of the reasons I'm leary of kilohertz or megahertz carrier waves for PEMF. Low frequency electrical stimulation of nerves has a regenerative effect, whereas high frequency can make nerve damage worse |
It has a power supply that keeps it at full power (still trying to source a variable power supply without dirty output).
At full power the coil gets slightly warm, but if you take measurements with the hall probe or your h field probe I am guessing it will reach farther than anything else you have right now. I did a lot of experimenting to try and find the smallest delta (as opposed to devices that are high intensity at the coil but it drops off really fast in a few inches)
At full power the coil gets slightly warm, but if you take measurements with the hall probe or your h field probe I am guessing it will reach farther than anything else you have right now. I did a lot of experimenting to try and find the smallest delta (as opposed to devices that are high intensity at the coil but it drops off really fast in a few inches)
Sawtooth on magnetic magic
My electric square wave is turned into a magnetic sawtooth because of the inductance of the coil and the configuration of the circuit. The magnetic field rises fast and falls slowly
My electric square wave is turned into a magnetic sawtooth because of the inductance of the coil and the configuration of the circuit. The magnetic field rises fast and falls slowly
Spectral content
After watching the video, it seems pretty clear that they are focused specifically on the results of the fourier transform. There are many ways to get the results to have a similar "spectral content", but the results can easily be manipulated depending on how you set up the parameters of the spectrum analyser.
I would want to see biological evidence in vitro that there enhanced "spectral content" is any better than a high slew rate square wave. If Bob Dennis is correct, there is likely not much difference in how the cells react
imagine that these different balls with different frequencies (the lengths being different and the weights assumed to be the same) represented different molecules resonant frequencies. If you hit them all at once each one will swing at its own resonant frequency. This would correspond to the square wave.
Then imagine that you could push each one at exactly the right time to keep them swinging. This would correspond to a high spectral distribution
Each should have an effect, but it would take some testing to see which is better. I personally like the square wave best still because it just lets everything resonate at it's own frequency naturally instead of forcing it
After watching the video, it seems pretty clear that they are focused specifically on the results of the fourier transform. There are many ways to get the results to have a similar "spectral content", but the results can easily be manipulated depending on how you set up the parameters of the spectrum analyser.
I would want to see biological evidence in vitro that there enhanced "spectral content" is any better than a high slew rate square wave. If Bob Dennis is correct, there is likely not much difference in how the cells react
imagine that these different balls with different frequencies (the lengths being different and the weights assumed to be the same) represented different molecules resonant frequencies. If you hit them all at once each one will swing at its own resonant frequency. This would correspond to the square wave.
Then imagine that you could push each one at exactly the right time to keep them swinging. This would correspond to a high spectral distribution
Each should have an effect, but it would take some testing to see which is better. I personally like the square wave best still because it just lets everything resonate at it's own frequency naturally instead of forcing it
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**To Properly Measure Intensity you need a high speed hall effect sensor**
I purchased 10 high speed hall effect sensors from digikey the other day. If you like I can send one to you. They will make very similar lines on your oscilloscope, but they have the advantage of being able to measure the actual strength of the field. It outputs 65mV per millitesla. It would be great to see a video showing which mat has the most uniform field. Based on my calculations the field is going to be well above the "safe" limits at the surface of the mat if they make 500uT 10" above the mat.
I purchased 10 high speed hall effect sensors from digikey the other day. If you like I can send one to you. They will make very similar lines on your oscilloscope, but they have the advantage of being able to measure the actual strength of the field. It outputs 65mV per millitesla. It would be great to see a video showing which mat has the most uniform field. Based on my calculations the field is going to be well above the "safe" limits at the surface of the mat if they make 500uT 10" above the mat.
Dr Pawluk Uses this Study to Determine how much intensity is needed to create 15 gauss in the body using the inverse square law.
https://www.medicalrent24.it/wp-content/uploads/2018/02/44-Effects-of-electrical-physical-stimuli-on-articular.pdf
Watch starting here:
https://youtu.be/XypkgXgbNAQ?si=SEQLq_jRYberD6si&t=1169
file:///Users/bryantmeyers1/Downloads/I-ONE_therapy_in_patients_undergoing_total_knee_ar%20(1).pdf
https://www.medicalrent24.it/wp-content/uploads/2018/02/44-Effects-of-electrical-physical-stimuli-on-articular.pdf
Watch starting here:
https://youtu.be/XypkgXgbNAQ?si=SEQLq_jRYberD6si&t=1169
file:///Users/bryantmeyers1/Downloads/I-ONE_therapy_in_patients_undergoing_total_knee_ar%20(1).pdf
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Slew Rate
One way of measuring the quality of a sensed signal is to look at the slew rate. The slew rate refers to the slope of the intrinsic signal (Figure 8) and is measured in volts/second.
In electronics, slew rate is defined as the change of voltage or current, or any other electrical quantity, per unit of time. This is similar to Faraday's law as it shows how rapidly a signal rises and falls.
In other cases, a maximum slew rate is specified in order to limit the high frequency content present in the signal, thereby preventing such undesirable effects as ringing or radiated EMI.
One way of measuring the quality of a sensed signal is to look at the slew rate. The slew rate refers to the slope of the intrinsic signal (Figure 8) and is measured in volts/second.
In electronics, slew rate is defined as the change of voltage or current, or any other electrical quantity, per unit of time. This is similar to Faraday's law as it shows how rapidly a signal rises and falls.
In other cases, a maximum slew rate is specified in order to limit the high frequency content present in the signal, thereby preventing such undesirable effects as ringing or radiated EMI.
Biphasic shocks are more effective than monophasic shocks and need lesser energy. Typically when 360 Joules are delivered for defibrillation in a monophasic defibrillator, 200 Joules are given in a biphasic defibrillator.
The proposed mechanism is that a single monophasic wave of energy is not able to depolarize all the myocardial cells. Some cells close to the electrode gets too much energy while those away from the electrode gets too little. Reversing the polarity helps to sweep off these cells as well. This response is sometimes called a ‘burping’ response of a biphasic waveform.
A prospective randomized evaluation compared monophasic and biphasic wave forms in 22 survivors of out of hospital cardiac arrest during implantation of a cardioverter defibrillator [1]. Of the patients, 15 (68%) had lower defibrillation threshold with biphasic pulse.
The proposed mechanism is that a single monophasic wave of energy is not able to depolarize all the myocardial cells. Some cells close to the electrode gets too much energy while those away from the electrode gets too little. Reversing the polarity helps to sweep off these cells as well. This response is sometimes called a ‘burping’ response of a biphasic waveform.
A prospective randomized evaluation compared monophasic and biphasic wave forms in 22 survivors of out of hospital cardiac arrest during implantation of a cardioverter defibrillator [1]. Of the patients, 15 (68%) had lower defibrillation threshold with biphasic pulse.