System and method for applying a low frequency magnetic field to biological tissues

Information

  • Patent Grant
  • 11826579
  • Patent Number
    11,826,579
  • Date Filed
    Monday, May 30, 2022
    2 years ago
  • Date Issued
    Tuesday, November 28, 2023
    12 months ago
  • Inventors
  • Original Assignees
    • Mannavibes Inc. (Los Gatos, CA, US)
  • Examiners
    • Huang; Wen W
    Agents
    • Hoffberg & Associates
    • Hoffberg; Steven M.
Abstract
A system and method for applying a low strength, low frequency magnetic field therapy to biological tissues. A coil is excited with a low frequency oscillating current, e.g., 10-1000 Hz. The coil is, e.g., 5-200 turns, having a diameter of 2-20 mm, and produces a magnetic field strength of about 0.01-5 mTelsa at a distance of 1 cm from the coil, or a cover over the coil, into the tissue. The current is preferably controlled by a smartphone or other programmable device controlled by a downloadable app in accordance with a PEMF program which may be separately downloaded or updated, and may be provided through an audio jack. Alternately, a digital interface and/or wireless interface may control the current. An app on the smartphone may be used to control the frequency, amplitude/envelope modulation, waveform, duration, etc. of the oscillation. The coil may be in mineral housing with a simple filter, and TRRS-type audio jack.
Description
INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.


BACKGROUND OF THE INVENTION
1. Field of the Invention

This invention pertains to a system and method for providing a therapeutic magnetic field at a frequency of about 5 Hz-50 kHz.


2. Discussion of Related Art

It is now well established that application of weak non-thermal electromagnetic fields (“EMF”) can result in physiologically meaningful in vivo and in vitro bioeffects. Time-varying electromagnetic fields, comprising rectangular waveforms such as pulsing electromagnetic fields (“PEMF”), and sinusoidal waveforms such as pulsed radio frequency fields (“PRF”) ranging from several Hertz, are clinically beneficial when used as an adjunctive therapy for a variety of musculoskeletal injuries and conditions.


Wade, Brett, “A Review of Pulsed Electromagnetic Field (PEMF) Mechanisms at a Cellular Level: A Rationale for Clinical Use”, American Journal of Health Research. Vol. 1, No. 3, 2013, pp. 51-55. doi: 10.11648/j.ajhr.20130103.13, also discusses various PEMF studies. Significant tissue healing effects, particularly with the modality PEMF, are likely the result of increased activity in non-excitable cells. Electromagnetic modalities include any modality which uses electricity and therefore generates both an electric field and a magnetic field. In physiotherapy practice, these electromagnetic modalities are generally used to expedite recovery of soft tissue injuries or alleviate pain. The movement of the electrons will cause ions to move towards the electrodes and thereby, ostensibly, affecting the physiology of the cell. Ions such as calcium (Ca2+), potassium (K+), sodium (Na+), chlorine (Cl), etc. Ions have numerous roles in the cellular physiology of cells. The movement of ions through ion channels in the plasma membrane and organelles have important roles in excitable and non-excitable cells such as nerve cell signal propagation, muscle contractions, energy production, etc. Electrotherapy education has traditionally attributed the positive effects of electrotherapy to the effects of an electric current causing a depolarization of excitable cells by the forced movement of ions (Na+ and K+) across the plasma membrane.


As previously described, negatively anions such as Cl will, in theory, be attracted to the positive charge of the externally applied electrode and positively charged ions such as Na+ and K+ will be attracted to the negative electrode. If the current used is a simple direct current (electrons flowing only in one direction), there would be build-up of same-charge ions concentrating in one area. This would have a significant effect on local pH due to increased concentrations of hydrochloric acid and sodium hydroxide leading to cause pain and cellular damage. Therefore, electrotherapy is usually the use of a direct current that is both pulsed and bi-directional to prevent excessive build-up of ions under an electrode. A paper published by Panagopoulos et al. (3) suggested a hypothesis whereby the externally applied electromagnetic field causes the ions to vibrate and when this vibration reaches a critical point, this gives a false signal to the voltage gated channels present in the membranes of eukaryotic cells. Once the channel receives a false signal, the gate may be forced to either open or perhaps close but theoretically affecting the physiology of the cell.


Panagopoulos et al. further describe how both the oscillating electric and magnetic fields can have similar effects on the free ions and consequently the voltage gated channels. It has long been argued that low frequency; non-ionizing radiation has no significant bioactive effects on cells. This, in fact, has been the argument for why wireless technology and the use of cellular telephones should have no negative effects to human health. The theory presented by Panagopoulos et al. suggests that, because of the inverse relationship between amplitude of the “ion's forced vibration” and frequency, lower frequency electromagnetic fields have the potential to be more bioactive. The authors provide a mathematical model which also explains how pulsed fields (on for a period and off for a period) are more bioactive than static fields of the same parameters, and their calculations demonstrate how either pulsed electromagnetic fields or the time of onset or removal of an external field will be twice as active as non-pulsatile fields. The calculations support other observations which have found bioactive effects with pulsed fields of extremely low frequency.


While any of the electromagnetic modalities can theoretically attribute their effects to both the electric and magnetic field, only PEMF is designed specifically to direct magnetic fields through the tissues to facilitate healing. The purported mechanism of action of magnetic fields on cells is has been suggested by Panagopoulos et al. Another paper by Ganesan et al. (4) reviewed the literature for PEMF in the treatment of arthritis. In addition to the effects suggested by Panagopoulos et al., Ganesan et al., suggest that Ca2+ may be modulated by the externally applied magnetic field which in turn could affect many important voltage gated aspects of cell physiology including gene activation, signal transduction, cAMP production, immune function, etc. Looking specifically at the effects of a pulsed magnetic field related to arthritis, Ganesan et al., review research which has found increased chondrocyte production in joints exposed to PEMF. The authors also review research which demonstrates a decrease in pro-inflammatory cytokines such as TNF-alpha and IL-6. In vitro studies have also demonstrated that PEMF has significant effects on both excitable and non-excitable cells leading to osteogenesis (5) and chondrocyte proliferation (6). The research into positive effects with PEMF and multiple sclerosis (MS) has found beneficial effects from PEMF using much weaker intensities (7). Sandyk has shown positive results with MS in the picotesla intensities (8).


If the electric field is created by a movement of electrons, the resultant magnetic field is also capable of inducing electric currents in a surrounding medium. The magnetic field created by the moving electrons is essentially a field of virtual photons creating force lines. This magnetic field is capable of causing movement of particles with an electric charge such as ions. This force is known as a Lorentz force. Since PEMF is not using an electric field per se, there is no electron flow with frequency and pulse width suitable for stimulating sensory or motor nerves. What the electric field and the magnetic field have in common is the forced movement of ions. If an externally applied electromagnetic field can cause the forced movement of ions across a plasma membrane and we know that these movements can affect cellular physiology, are there “windows” of frequency and intensity which may be more effective? The parameters which have shown to be the most effective with PEMF in treating pathologies such as: bone healing, wound healing, ligament healing, and cartilage-healing range from 15-75 Hz and use intensities in the militesla range. Markov (9) has suggested “three amplitude windows” with PEMF: 50-100 μT, 15-20 mT, and 45-50 mT. Summarized below are some of the effects on non-excitable cells exposed to PEMF.


Cells Mechanism, PEMF parameters, References


Chondrocytes Increased number of chondrocytes 75 Hz, 2.3 mT (Murray 1985)


Osteoblasts Increased proliferation of osteoblasts 15 Hz, 0.1 mT (Marino 1970)


Osteoclasts Decreased production of osteoclasts 7.5 Hz, 300 μs,


Neutrophils Saturates adenosine receptors leading to decreased inflammatory cytokine cascade 75 Hz, 0.2 mT-3.5 mT (Doillon 1987)


Mononuclear Significant increased IL-1β & TNF-α (Pro inf. cytokines) 50 Hz, 2.25 mT (Doillon 1986)


Fibroblasts Red. cAMP leads to increased proliferation of collagen cells 15 Hz, 4.8 ms pulse (Basset 1981)


Endothelial Increased proliferation of endothelial cells leading to angiogenesis. 50 Hz, 1 mT (Brighton 1981)


In general, the PEMF mats use frequencies that range from 5-300 Hz which is generally classified in a range of electromagnetic frequencies known as extremely low frequency (ELF). The magnetic field intensities used by these machines are usually in the micro and millitesla range.


The research to date has shown that the mechanisms by which PEMF works are complicated and likely involve many pathways. It is clear that certain windows of frequency and intensity are capable of increasing mitosis in cells such as chondrocytes, osteoblasts, fibrocytes and endothelial cells. These effects will lead to improved healing time of soft tissues and bone. In addition to increasing cell metabolism, perhaps PEMF's greatest power is in its ability to ameliorate the effects of inflammation by decreasing inflammatory cytokines. This effect should give the practitioner cause to consider PEMF in the treatment of numerous inflammatory conditions including, perhaps, autoimmune diseases such as MS. It is also conceivable, as suggested by Gordon (2007), that another important effect of PEMF is the ability of the magnetic fields to restore “equilibrium in ROS (free radical)/antioxidant chemistry. Gordon (2007) explains that since both reactive oxygen species (ROS) free radicals such as superoxide anion (O.) and hydroxyl anion (OH.) are paramagnetic, they will be affected by a magnetic field. This forced vibration (similar to the effect on ions such as K+, Na+, Cl, Ca2+) is thought to enhance the homeostasis between ROS and antioxidants. It is unequivocal that all chronic diseases result from a lack of homeostasis between free radicals and antioxidants. While both free radicals and antioxidants are normal and vital for processes such as cellular respiration and immunity, an imbalance could lead to cell and tissue death, DNA damage, and protein and fat degradation.


U.S. 20110112352 discloses an apparatus and method for electromagnetic treatment, in which electromagnetic treatment devices are provided for treatment of tissue. These are intended to apply energy within a specific bandpass of frequencies of a target biological pathway, such as the binding of Calcium to Calmodulin, and thereby regulate the pathway. The device provides for example, a field having an amplitude of between about 1 μV/cm to about 100 mV/cm at the target tissue and a peak induced magnetic field between about 1 μT and about 20 μT. The control circuit generates a burst of waveforms having a burst duration of greater than 0.5 msec and a burst period of between about 0.1 to about 10 seconds to produce a signal that is above background electrical activity.


The use of most low frequency EMF has been in conjunction with applications of bone repair and healing. As such, EMF waveforms and current orthopedic clinical use of EMF waveforms comprise relatively low frequency components and are of low power, inducing maximum electrical fields in a millivolts per centimeter (mV/cm) range at frequencies under five KHz. A linear physicochemical approach employing an electrochemical model of cell membranes to predict a range of EMF waveform patterns for which bioeffects might be expected is based upon an assumption that cell membranes, and specifically ion binding at structures in or on cell membranes, are a likely EMF target.


Time-varying electromagnetic fields, comprising rectangular waveforms such as pulsing electromagnetic fields, and sinusoidal waveforms such as pulsed radio frequency fields ranging from several Hertz to an about 15 to an about 40 MHz range, may be clinically beneficial when used as an adjunctive therapy for a variety of musculoskeletal injuries and conditions.


U.S. Pat. No. 9,278,231 discloses a system for inducing cellular regeneration and/or degeneration processes and methods of treatment based on such processes through generating and applying a sequentially programmed magnetic field (SPMF) to the area to be treated. In the case of regeneration and degeneration of cells, the pulsing frequencies are in the range of about 0.1 to about 2000 Hz based on the indication of the disease type. A magnetic field generating device is provided comprising: a magnetically conductive hollow cylindrical base body; a funnel at one end of said magnetically conductive hollow cylindrical base body which increases in diameter as it extends from the cylindrical base body to a terminal rim-like portion; a magnetically conductive rod-like structure extending along a central axis through said hollow cylindrical base body into an interior of said funnel; and an electrical coil wound circumferentially around the magnetic field generating device from the other end of the hollow cylindrical base body to the rim-like portion of the funnel.


U.S. Pat. No. 9,278,231 notes that electromagnetic fields of certain frequency ranges and intensities are indigenous to living tissues and it has been found that inciting the inherent resonance by exogenous treatment using electromagnetic fields [EMF], electric fields, and magnetic fields can induce cellular regeneration and degeneration processes. EMF in a range from 0.1-150 Hz have been reported to stimulate bone cells. It has also been reported that bone resorption that normally parallels disuse can be prevented or even reversed by the exogenous induction of electric fields. Electromagnetic fields below 10 μV/cm, when induced at frequencies between 50 and 150 Hz for 1 h/day, are sufficient to maintain bone mass even in the absence of function. Reducing the frequency to 15 Hz makes the field extremely osteogenic. This frequency-specific sinusoidal field initiated more new bone formation than a more complex pulsed electromagnetic field (PEMF), though inducing only 0.1% of the electrical energy of the PEMF.


U.S. Pat. No. 8,968,172 discloses a cell excitation terminal and a therapeutic system using customized electromagnetic (EM) waves varying dynamically with time for excitation include one or more EM wave generators, each of the EM wave generators is connected to a central processing unit (CPU), and the CPU controls, according to a signal detected by a human body status detection device, the EM wave generator to send EM waves corresponding to a detected subject. The therapeutic system can perform remote management. A remote server optimizes and updates therapeutic waveforms of a patient constantly according to a therapeutic effect of the patient, thereby improving the therapeutic effect constantly.


U.S. Pat. No. 8,911,342 relates to an apparatus and a method for stimulating brain tissue with pulsed electromagnetic fields weaker than the limit for elicitation of the action potentials of the cells of the tissue to be stimulated, the apparatus comprising: at least one electrically conducting coil positioned at a bitemporal position such that hippocampus is stimulated by at least one magnetic field upon supplying a pulse to said coil as well as a coil positioned at a occipital and parietal position; and a pulse generation means operationally connected to said at least one coil for supplying a series of current pulses for conduction, allowing generation of pulsed electromagnetic fields sufficiently strong to cause protein activation, and weaker than the limit for elicitation of the action potentials of the cells of the tissue to be stimulated.


U.S. Pat. No. 9,427,598 relates to methods of treating neurological injury and conditions, in particular, traumatic brain injury and physiological responses arising from injury or conditions. These treatment methods can include the steps of generating a pulsed electromagnetic field from a pulsed electromagnetic field source and applying the pulsed electromagnetic field 1 in proximity to a target region affected by the neurological injury or condition to reduce a physiological response to the neurological injury or condition.


U.S. Pat. No. 9,421,357 discloses systems, apparatuses, and methods for providing non-transcranial electrical stimuli to a biological subject may employ a support structure, at least one waveform generator, and at least a first electrode and a second electrode. The system can be sized and dimensioned to be worn on a head of the biological subject and operable to deliver non-transcranial electrical stimuli to at least one of the temporomandibular joints of the biological subject.


The use of electrical energy to produce modifications in living tissue is well known. Electro-magnetic devices have been used to promote healing of broken bones. Barker (1981). Additionally, use of pulsed electro-magnetic fields (PEMF) to promote healing of bone tissue is described in U.S. Pat. No. 4,315,503 to Ryaby, et al. and in U.S. Pat. No. 3,890,953 to Kraus, et al. Use of electro-magnetic energy to arrest arthritic pain has been disclosed in U.S. Pat. No. 3,902,502 to Liss, et al. There is little agreement so far amongst researchers in the field as to the most effective pulse wave form, frequency, and voltage level for treatment of tissue disorders.


Wound repair involves cellular events such as cell migration, replication, synthesis and deposition of new connective tissue, remodeling and epidermal cell migration over dermal repair tissue. Many studies suggest that these events may be influenced by endogenous and exogenous electric or magnetic fields in both soft and hard tissue. Electrical stimulation using direct electrical currents or induced voltages and currents has been shown to affect wound healing. Typical methods for the use of electric current in the promotion of healing are those methods employing low intensity direct current (LIDC) and, more recently, pulsed electromagnetic fields (PEMF). Electric current was initially employed to promote the healing bone fractures, especially those fractures demonstrating non-union. Several patents have issued for methods and devices for the use of PEMF's to promote bone healing. U.S. Pat. No. 3,915,151 issued to Kraus describes a magnetic coil device for the induction of electric current by the application of a magnetic field to injured bones and related soft tissues. U.S. Pat. No. 4,233,965 issued to Fairbanks describes a similar method and device using PEMF's to induce an electric current for the healing of bone and connective tissue, improved to achieve a deeper penetration of electrical current, especially for the treatment of arthritis. U.S. Pat. No. 4,556,051, issued to Maurer describes a device and method for promoting the healing of fractured bones and related connective tissue through the simultaneous application of PEMF's and pulsed electric current in a fixed phase relationship to produce a net current in the region of the fractured bone generally perpendicular to the plane of the fracture. U.S. Pat. No. 4,674,482 issued to Waltonen, et al describes a method and device for the promotion of vasoconstriction through the application of PEMF's. The inventor describes the device as an “electric icepack.” A biasing circuit is described that prevents the occurrence of a reverse polarity pulse upon the fall of the magnetic flux induced by the fall of the generated pulse, thereby diminishing high frequency ringing at the beginning of a treatment signal and improving the promotion of vasoconstriction. U.S. Pat. No. 4,461,300 issued to Christiensen describes a method and device employing cathodic LIDC to promote the healing of fractures and injuries to bones and related soft tissues. A specifically designed cathodic electrode implant assembly with a particular method of implantation at the fracture or bone defect site is disclosed.


U.S. Pat. No. 3,893,462 issued to Manning, which describes a method and device employing an undulating electrical signal having a wave form whose rise time differs from its fall time, in turn producing a voltage at the tissue level that is bipolar with the amplitude and frequency components of one polarity differing from those of the opposite polarity, effecting the bioelectrical signals at the cellular or tissue level, thereby artificially stimulating the healing of the cells and/or tissue.


With respect to PEMF's, Bassett (1984), discloses that when a dynamic, magnetic field passes through a static conductor, such as wound tissue, an electric field is induced in the conductor, with voltages of 1.0 to 1.5 millivolts per centimeter. Bassett states that the current induced varies with time. Bassett (1984) suggests that PEMF's promote collagen growth. Goodman (1983), describes the stimulation of messenger RNA specific activity by PEMF's of 0.1 G per micro second. Murray (1985) describes the increase in collagen production in cell cultures produced by low frequency PEMF's. The field was generated by a generator-driven pair of Helmholtz-aiding air cored coils. Leaper (1985), on the other hand, disclosed that a 400 Gauss magnetic field was found not to promote wound healing. McLeod (1987), describes the use of AC electric fields of 0.1-1000 Hz frequency to promote proline incorporation into fibroblast populated collagen matrices.


Pawluk (2015) provides a review of PEMF for pain, and notes that static EMFs have been used for centuries to control pain and other biologic problems. After thousands of patient-years of use globally, very little risk has been found to be associated with MF therapies (Markov, 2004). Standards and guidelines for safety have been promulgated and published (ICNIRP, 2010). The primary precautions or contraindications relate to implanted electrical devices, pregnancy (because of lack of data), and seizures with certain kinds of frequency patterns in seizure-prone individuals. MFs affect pain perception in many different ways. These actions are both direct and indirect. Direct effects of MFs are on neuron firing, calcium ion movement, membrane potentials, endorphin levels, nitric oxide, dopamine levels, acupuncture actions, and nerve regeneration. Indirect benefits of MFs from physiologic function enhancement are on circulation, muscle, edema, tissue oxygen, inflammation, healing, prostaglandins, cellular metabolism, and cell energy levels (Jerabek and Pawluk, 1996). Pain relief mechanisms vary by the type of stimulus used (Takeshige and Sato, 1996). For example, needling to the pain-producing muscle, application of a static MF or external qigong, or needling to an acupuncture point all reduce pain by different mechanisms. In guinea pigs, pain could be induced by reduction of circulation in the muscle (ischemia) and reduced by recovery of circulation. Muscle pain relief is induced by recovery of circulation due to the enhanced release of acetylcholine as a result of activation of the cholinergic vasodilator nerve endings innervated to the muscle artery (Takeshige and Sato, 1996).


Several authors have reviewed the experience with PEMFs in Eastern Europe (Jerabek and Pawluk, 1996) and elsewhere (Trock, 2000) and provided a synthesis of the typical physiologic findings of practical use to clinicians, resulting from magnetic therapies. These include, at a minimum, reduction in edema and muscle spasm/contraction, improved circulation, enhanced tissue repair, and natural antinociception. These are the fundamentals of the repair of cell injury. PEMFs have been used extensively in many conditions and medical disciplines, being most effective in treating rheumatic or musculoskeletal disorders. PEMFs produced significant reduction of pain, improvement of spinal functions, and reduction of paravertebral spasms. In clinical practice, PEMFs have been found to be an aid in the therapy of orthopedic and trauma problems (Borg et al., 1996). The ability of PEMFs to affect pain is at least in part dependent on the ability of PEMFs to positively affect human physiologic or anatomic systems. The human nervous system is strongly affected by therapeutic PEMFs (Prato et al., 2001). Animals exposed to static and extremely low-frequency (ELF) MFs are also affected by the presence of light, which strengthens the effects of PEMFs (Prato et al., 1999). One of the most reproducible results of weak ELF MF exposure is an effect upon neurologic pain signal processing (Thomas and Prato, 2002). This evidence suggests that PEMFs would also be an effective complement for treating patients suffering from both chronic and acute pain.


The placebo response may explain as much as 40% of an analgesia response from any pain treatment (Colloca et al., 2013), and needs to be accounted for in research design to assure adequate sample sizes. However, aside from this aspect of accounting for the placebo effect, the central nervous system mechanisms responsible for the placebo response, that is, central cognitive and behavioral processes, can be addressed directly in managing pain and include medications, hypnosis, mindfulness meditation, and psychotherapy. In addition, these placebo response-related central processes appear to be an appropriate target with magnetic therapies for managing pain. Amplifying MF manipulation of cognitive and behavioral processes has been evaluated in animal behavior studies and in humans, affecting at the very least opiate receptors (Del Seppia et al., 2007). Therefore, amplifying the placebo response with centrally focused MFs would generally be expected to be additive to pain management using MF therapies elsewhere on the body.


Cell injury itself involves multiple processes (Kumar, 2007), which, if mitigated, can be expected to reduce the perception of pain and limit the results of the cell injury. Therefore, this is the goal of clinical management. If the cause of pain cannot be reduced or eliminated, then the goals of pain management shift to reducing the perception of pain or blocking the pain signal traffic otherwise. Research on the use of PEMFs for pain management focuses on the multiple mechanisms of the production of pain. The primary mechanisms of the production of pain in local tissue in response to cell injury include, to varying degrees, edema, apoptosis or necrosis, diminished vascular supply, reduced cellular energy production, and impaired repair processes. PEMF therapies address many of these different aspects of cell injury (Jerabek and Pawluk, 1996). Magnetic therapy increases the threshold of pain sensitivity (Thomas and Prato, 2002) and activates the anticoagulation system (Khamaganova et al., 1993), which increases circulation to tissue. PEMF treatment stimulates production of opioid peptides, activates mast cells and increases electric capacity of muscular fibers, helps with edema and pain before or after a surgical operation (Pilla, 2013), increases amino acid uptake (De Loecker et al., 1990), and induces changes in transmembrane energy transport enzymes, allowing energy coupling and increased biologic chemical transport work.


Healthy humans normally have reduced pain perception and decreased pain-related brain signals (Prato et al., 2001). Biochemical changes in the blood of treated patients are found that support the pain reduction benefit. PEMFs cause a significant improvement in normal standing balance in adult humans (Thomas et al., 2001). PEMFs couple with muscular processing or upper-body nervous tissue functions, which indicate CNS sensitivity that likely improves central pain processing.


Various kinds of PEMFs have been found to reduce pain. For example, various MFs applied to the head or to an extremity, for 1-60 min, with intervals between exposures from several minutes to several hours, randomly sequenced with sham exposures allowed the study of brain reactions by various objective measures (Kholodov, 1998). EEGs showed increased low-frequency rhythms. Low-frequency EEG rhythms may explain the common perception of relaxation and sleepiness with ELF EMFs. Even weak AC MFs affect pain perception and pain-related EEG changes in humans (Sartucci et al., 1997). A 2 h exposure to 0.02-0.07 mT ELF MFs caused a significant positive change in pain-related EEG patterns.


The benefits of PEMF use may last considerably longer than the time of use. This is a common clinical observation. In rats, a single exposure produces pain reduction both immediately after treatment and even at 24 h after treatment (Cieslar et al., 1994). The analgesic effect is still observed at the 7th and 14th day of repeated treatment and even up to 14 days after the last treatment. Repeated presentation of painful stimuli in rats can significantly elevate the threshold of response to painful stimuli. One group (Fleming et al., 1994) investigated the ability of magnetic pulse stimuli to produce increases in pain thresholds, simulating thalamic pain syndrome. Exposure to the PEMFs increased the pain threshold progressively over 3 days. Pain suppression was maintained on the second and third days relative to other treatments. The pain threshold following the third MF exposure was significantly greater than those associated with morphine and other treatments. Brain-injured and normal rats both showed a 63% increase in mean pain threshold. The mechanism may involve endorphins, having important implications for clinical practice and the potential for a reduction in reliance on habit-forming medications.


PEMFs promote healing of soft tissue injuries by reducing edema and increasing resorption of hematomas (Markov and Pilla, 1995), thereby reducing pain. Low-frequency PEMFs reduce edema primarily during treatment sessions. PEMFs at very high frequencies applied for 20-30 min cause decreases in edema lasting several hours following an exposure session. PEMF signals induce maximum electric fields in the mV/cm range at frequencies below 5 kHz.


Chronic pain often occurs from aberrant small neural networks with self-perpetuated neurogenic inflammation. It is thought that high-intensity pulsed magnetic stimulation (HIPMS) noninvasively depolarizes neurons and can facilitate recovery following injury (Ellis, 1993). HIPMS, intensity up to 1.17 T, was used to study recovery after injury in patients with posttraumatic/postoperative low-back pain, reflex sympathetic dystrophy (RSD), neuropathy, thoracic outlet syndrome, and endometriosis. The outcome VAS difference was 0.4-5.2 with sham treatments versus 0-0.5 for active treatments. The author proposed that the pain reduction was likely due to induced eddy currents.


Effects on the tissues of the body and the symptoms of pain have been found across a wide spectrum of electromagnetic frequencies, including high-frequency PEMFs. For example, significant reductions in pain were found in individuals with acute whiplash injuries using 27.12 MHz PEMF stimulation (Foley-Nolan et al., 1992). The same group (Foley-Nolan et al., 1990) had previously found that individuals with persistent neck pain lasting greater than 8 weeks had statistically significantly greater improvement in their pain compared to controls. The controls were then crossed over onto PEMF treatment and had similar results.


For more detailed discussion of the potential mechanisms of action of MFs to treat pain, see Markov (2004). The author discusses some of the parameters that may be necessary to properly choose a therapeutic MF with respect to the target tissue to be stimulated. The research literature on magnetic therapies for pain management is very variable in describing the particular parameters of the magnetic therapy apparatus being studied. This leaves the clinician at a significant disadvantage in determining which MFs produce the best results for the given condition being treated. Further, the author states, “during the past 25 years more than 2 million patients have been treated worldwide for a large variety of injuries, pathologies and diseases. This large number of patients exhibited a success rate of approximately 80%, with virtually no reported complications.” The author goes on to describe a number of mechanisms of cellular action of EMFs that may be deemed responsible for the therapeutic benefit in improving pain. In another study, Shupak et al. (2004) looked at possible mechanisms or influencing factors for the effects of PEMFs on pain, especially on sensory and pain perception thresholds. It appears that MF exposure does not affect temperature perception but can increase pain thresholds, indicating an analgesic effect. Based on the review by Del Seppia et al. (2007), it appears that at least one of the mechanisms involved in PEMF effects on pain and nociception is the opiate receptor. Another study in rats (Fleming et al., 1994) found that there was an analgesic effect comparable to more noxious tactile stimulation, that is, stress-induced analgesia. There was an approximately 50% increase in the pain threshold in response to electrical current stimulation.


In a study to gain a better understanding of pain perception (Robertson et al., 2010), a functional magnetic resonance imaging study was done to assess how the neuromodulation effect of MFs influences the processing of acute thermal pain in normal volunteers. ELF MFs (from DC to 300 Hz) have been shown to affect pain sensitivity in snails, rodents, and humans. Because of this research, it is unlikely that a pure placebo response is involved. This neuroimaging study found changes in specific areas of the brain with pain stimuli that are definitely modified by low-intensity PEMF exposure.


Chronic pain is often accompanied with or results from decreased circulation or perfusion to the affected tissues, for example, cardiac angina or intermittent claudication. PEMFs have been shown to improve circulation (Guseo, 1992). Pain syndromes due to muscle tension and neuralgias improve.


Peripheral neuropathy can be an extremely painful condition that is very challenging to manage. Two randomized controlled studies failed to show significant results in diabetic peripheral neuropathy (DPN) (Wróbel et al., 2008; Weintraub et al., 2009). Another two studies showed significant improvements in DPN (Cieslar et al., 1995; Graak et al., 2009). There were significant methodological differences among the studies.


A large study (Weintraub et al., 2009) was conducted to determine whether repetitive and cumulative exposure to low-frequency PEMF to the feet can reduce neuropathic pain (NP) and influence nerve regeneration. Two-hundred and twenty-five patients with DPN stage II or III were randomized in a double-blind, placebo-controlled parallel study, across 16 academic and clinical sites in 13 states to PEMF or sham (placebo) devices. They applied their treatments 2 h per day to their feet for 3 months. Pain reduction scores were measured using a VAS, the neuropathy pain scale (NPS), and the patient's global impression of change (PGIC). A subset of subjects underwent serial 3 mm punch skin biopsies from three standard lower-limb sites for epidermal nerve fiber density (ENFD) quantification. There was a significant dropout rate of 13.8%. The PEMF versus sham group had reductions in DPN symptoms on the PGIC (44% versus 31%; p=0.04). There were no significant differences in the NP intensity on NPS or VAS. Of the 27 patients who completed serial biopsies, 29% of the PEMF group had an increase in the distal leg ENFD of at least 0.5 SDs, while none did in the sham group (p=0.04). Those with increases in distal thigh ENFD had significant decreases in pain scores. The conclusion was that PEMF at this dose was not effective specifically in reducing NP. However, neurobiological effects on ENFD, PGIC, and reduced itching scores were hopeful and suggest that future studies should be attempted with higher PEMF intensities 3000-5000 G, longer duration of exposure, and a larger biopsy cohort. Since most of the therapeutic approaches to DPN have poor success rates, relying mostly on the suppression of pain with medications, this study is encouraging in actually demonstrating potential nerve regeneration improvements.


Another randomized, placebo-controlled, double-blind study (Wróbel et al., 2008) was conducted to assess an ELF PEMF effect on pain intensity, quality of life and sleep, and glycemic control in patients with painful diabetic polyneuropathy. Sixty-one patients were randomized into a study group of 32 patients exposed to a low-frequency, low-intensity MF or a sham control group of 29 patients. Pain durations were greater than 2 years in both groups. Treatments were for 3 weeks, 20 min a day, 5 days a week. Questionnaires, completed at the beginning, after 1-3 and 5 weeks, included SFMPQVAS (pain evaluation), EuroQol EQ-5D, and MOS Sleep Scale. Significant reductions in pain intensity were seen in both the study group, VAS 73 mm at baseline versus 33 mm after 3 weeks, and controls, VAS 69 mm at baseline versus 41 mm after 3 weeks. The extent of pain reduction did not differ significantly between the groups at any time. The conclusion was that this low-intensity ELF PEMF, used for only 3 weeks, had no advantage over sham exposure in reducing pain intensity. In the Weintraub study, patients were treated for 3 months, providing a longer opportunity to produce sustainable changes in the tissues. Since neuropathy is a very stubborn problem to treat, it is likely that both of these neuropathy studies were too short for the severity of neuropathy present, treatment protocols, measures, and equipment used.


In another study (Graak et al., 2009) on NP, using low-power, low-frequency PEMF of 600 and 800 Hz, 30 patients, 40-68 years of age with DPN stages N1a, N1b, N2a, were randomly allocated to three groups of 10 in each. Groups 1 and 2 were treated with low-power 600 and 800 Hz PEMF, respectively, for 30 min for 12 consecutive days. Group 3 served as control on usual medical treatment. Pain and motor nerve conduction parameters (distal latency, amplitude, nerve conduction velocity) were assessed before and after treatment. They found significant reduction in pain and statistically significant (p<0.05) improvement in distal latency and nerve conduction velocity in experimental Groups 1 and 2. Using this particular protocol, low-frequency PEMF was seen to reduce NP as well as for retarding the progression of neuropathy even when applied for only a short span of time. What could happen with longer-term treatment remains to be determined.


Thirty-one patients with diabetes mellitus (type I and II), with intense symptoms of neuropathy, were treated (Cieslar et al., 1995). They had 20 exposures to variable sinusoidal PEMF, 40 Hz, 15 mT, every day for 12 min. Reduction of pain and paresthesias, vibration sensation, and improved muscle strength was seen in 85% of patients, all significantly better than sham controls.


Carpal tunnel syndrome is another form of neuropathy, affecting the median nerve at the wrist. There are many different approaches to the treatment of carpal tunnel syndrome, including surgery, with varying success. In a randomized, double-blinded, placebo-controlled trial (Weintraub and Cole, 2008), a commonly commercially available combination of simultaneous static and dynamic, rotating time-varying dynamic MFS was used to treat the wrist. There was a significant reduction of deep pain. Ten months of active PEMF resulted in improvement in nerve conduction and subjective improvement on examination (40%), pain scores (50%), and a global symptom scale (70%).


The neuropathy of postherpetic neuralgia, a very common and painful condition, often medically resistant, responded to PEMF (Kusaka et al., 1995). A combination static and pulsed MF device was placed on the pain/paresthesia areas or over the spinal column or limbs. Treatments continued until symptoms improved or adverse side effects occurred. Therapy was effective in 80%. This treatment approach shows that treatment for pain problems may either be localized to the area of pain or over the spinal column or limbs, away from the pain. Treatment over the appropriate related spinal segment offers the opportunity to interrupt the afferent pain signal traffic to the brain. This approach has been frequently used with success in Eastern European studies (Jerabek and Pawluk, 1996). Another author reported a more general clinical series in postherpetic pain in which better results happened in patients simultaneously suffering from neck and low-back pain (Di Massa et al., 1989).


Posttraumatic, late-stage RSD, or now called regional complex pain syndrome (CRPS), a form of neuropathy, is very painful and largely untreatable by standard medical approaches. In one report, ten 30 min PEMF sessions of 50 Hz followed by a further 10 sessions at 100 Hz plus physiotherapy and medication reduced edema and pain at 10 days (Saveriano and Ricci, 1989). There was no further improvement at 20 days. The author had a personal case treated with a 27.12 MHz PEMF signal, in a nurse who was almost completely disabled in her left upper extremity. She used her device for about an hour a day. Within about 1 month, she had about 70% recovery, and within 2 months, she had essentially normal function with no further sensitivity to touch, changes in temperature, etc. She maintained her recovery with continued treatments in the home setting.


Musculoskeletal conditions, especially with related pain, are most frequently treated with MF therapies. Among these, one of the most common conditions is lumbar arthritis, as a cause of back pain. Chronic low-back pain affects approximately 15% of the US population during their lifetime (Preszler, 2000). Given the current treatment options available through conventional medical therapy, with their attendant risks, there is a large unmet need for safe and effective alternative therapies (Institute of Medicine, 2005).


PEMFs of 35-40 mT give relief or elimination of pain about 90%-95% of the time for lumbar OA, improve results from other rehabilitation therapies, and secondarily, additionally improve related neurologic symptoms (Mitbreit et al., 1986). Even PEMFs of 0.5-1.5 mT used at the site of pain and related trigger points also help (Rauscher and Van Bise, 2001). Some patients remained pain free 6 months after treatment.


In a series of 240 patients treated in an orthopedic practice with PEMFs, patients had decreased pain (Schroter, 1976) from rheumatic illnesses, delayed healing process in bones, and pseudoarthritis, including those with infections, fractures, aseptic necrosis, venous and arterial circulation, RSD (all stages), osteochondritis dissecans, osteomyelitis, and sprains and strains and bruises. The clinically determined success rate approached 80%. About 60% of loosened hip prostheses have subjective relief of pain and walk better, without a cane. Even so, x-ray evidence of improvement was seen periodically, as evidenced by cartilage/bone reformation, including the joint margin. If the goal in pain management is to heal the underlying tissue, not just manage symptoms, evidence, typically from imaging studies, can drive the duration of treatment to obtain the most long-lasting and more permanent results.


The use of PEMFs is rapidly increasing and extending to soft tissue from its first applications to hard tissue (Pilla, 2013). EMF in current orthopedic clinical practice is frequently used to treat delayed and nonunion fractures, rotator cuff tendinitis, spinal fusions, and avascular necrosis, all of which can be very painful. Clinically relevant response to the PEMF is generally not always immediate, requiring daily treatment for upward of a year in the case of nonunion fractures. PRF applications appear to be best for the reduction of pain and edema. The acute tissue inflammation that accompanies the majority of traumatic and chronic injuries is essential to the healing process; however, the body often over-responds in the chronic lesion situation, and the resulting edema causes delayed healing and chronic pain. Edema reduction is an important target for PRF and PEMF applications.


Even chronic musculoskeletal pain treated with MFs for only 3 days, once per day, can eliminate and/or maintain chronic musculoskeletal pain (Stewart and Stewart, 1989). Small, battery-operated PEMF devices with very weak field strengths have been found to benefit musculoskeletal disorders (Fischer, 2002). Because of the low strength used, treatment at the site of pain may need to last between 11 and 132 days, between two times per week, 4 h each, and, if needed, continuous use. Use at night could be near the head, for example, beneath the pillow, to facilitate sleep. Pain scale scores are significantly better in the majority of cases. Conditions that can be considered for treatment are arthritis, lupus erythematosus, chronic neck pain, epicondylitis, patellofemoral degeneration, fracture of the lower leg, and RSD/CRPS.


Back pain or whiplash syndrome treated with a very low-intensity (up to 30 μT) PEMF twice a day for 2 weeks along with usual pain medications relieves pain in 8 days in the PEMF group versus 12 days in the controls (Thuile and Walzl, 2002). Headache is halved in the PEMF group, and neck and shoulder/arm pain improved by one-third versus medications alone. PEMFs have been found (Kjellman et al., 1999) to have more benefit in the treatment of neck pain in some research, compared to physical therapy, for both pain and mobility.


A blinded randomized study was conducted to compare European spa therapy (ST) with PEMF therapy in chronic neck pain (Forestier et al., 2007a). There was significantly greater improvement in the PEMF group than the ST group (p=0.02). As part of the earlier study, the authors also did a cost-benefit analysis (Forestier et al., 2007b).


One group evaluated pain and swelling after distal radius fractures after an immobilization period of 6 weeks (Cheing et al., 2005). Eighty-three patients were randomly allocated to receive 30 min of either ice plus PEMF (group A), ice plus sham PEMF (group B), PEMF alone (group C), or sham PEMF for 5 consecutive days (group D). All had a standard home exercise program. Outcome measures included a VAS for recording pain, volume displacement for measuring the swelling of the forearm, and a handheld goniometer for measuring the range of wrist motions. They were assessed, before treatment, and on days 1, 3, and 5 during treatment. At day 5, a significantly greater cumulative reduction in VAS as well as improved ulnar deviation ROM was found in group A than the other three groups. For volumetric measurement and pronation, participants in group A performed better than subjects in group D but not those in group B. The end result was that the addition of PEMF to ice therapy produces better overall treatment outcomes than ice alone, or PEMF alone, in pain reduction and ulnar ROM. This study points out the cumulative benefit of using both PEMFs and standard therapy, at least in radial fractures.


Many therapeutic approaches for treatment of lateral epicondylitis (tennis elbow) have been used, including local steroid injection and surgery. PEMFs have been found as a useful and safe candidate therapy. One group tested the efficacy of PEMF compared to sham PEMF and local steroid injection (Uzunca et al., 2007). Sixty patients with lateral epicondylitis were randomly and equally distributed into three groups as follows: group I received PEMF, group II sham PEMF, and group III a corticosteroid+anesthetic agent injection. Pain levels during rest, activity, nighttime, resisted wrist dorsiflexion, and forearm supination were investigated with VAS and algometer. All patients were evaluated before treatment, at the third week, and the third month. VAS values during activity and pain levels during resisted wrist dorsiflexion were significantly lower in group III than group I at the third week. Group I patients had lower pain during rest, activity, and nighttime than group III at the third month. PEMF appears to reduce lateral epicondylitis pain better than sham PEMF. Corticosteroid and anesthetic agent injections can be used in patients for rapid return to activities, along with PEMFs to produce a longer-standing benefit.


Another randomized sham-controlled study (Devereaux et al., 1985) on lateral humeral epicondylitis (tennis elbow) involved 30 patients with both clinical and thermographic evidence of tennis elbow. PEMF treatment, consisted of 15 Hz, delivering 13.5 mV and using a figure of eight coil with the loops over each epicondyle for 8 h a day in one or two sessions, for a minimum period of 8 weeks. They were significant improvements in grip strength at 6 weeks, with a slight decrease in difference at 8 weeks. There was little difference in the first 4 weeks. Since there were only 15 subjects in each treatment group, this study was probably underpowered for most of the other measurement indices used.


Osteoarthritis (OA) affects about 40 million people in the United States. OA of the knee is a leading cause of disability in the elderly. Medical management is often ineffective and creates additional side-effect risks. Many patients with OA of the knee/s undergo many soft tissue and intra-articular injections, physical therapy, and many, eventually, arthroscopies or joint replacements. An ELF sawtooth wave, 50 μT, whole-body and pillow applicator system has been in use for about 20 years in Europe. In one study using the system, applied 8 min twice a day for 6 weeks, it was shown to improve knee function and walking ability significantly (Pawluk et al., 2002). Pain, general condition, and well-being also improved. Medication use decreased. Plasma fibrinogen, C-reactive protein (a sign of inflammation), and the sedimentation rate all decreased by 14%, 35%, and 19% respectively. Sleep disturbances often contribute to increased pain perception. It was found to improve sleep, with 68% reporting good/very good results. Even after 1 year follow-up, 85% claim a continuing benefit in pain reduction. Medication consumption decreases from 39% at 8 weeks to 88% after 8 weeks.


In a randomized, placebo-controlled study (Ay and Evcik, 2009), PEMF of 50 Hz, 105 μT, applied for 30 min, was used in 55 patients with grade 3 OA for only 3 weeks for pain relief and enhancing functional capacity of patients with knee OA. Pain improved significantly in both groups relatively equally (p<0.000). However, there was significant improvement in morning stiffness and activities of daily living (ADL) compared to the control group. They did not find a beneficial symptomatic effect of PEMF in the treatment of knee OA in all patients.


In a rheumatology clinic study of knee OA (Pipitone and Scott, 2001), 75 patients received active PEMF treatment by a unipolar magnetic device or placebo for 6 weeks. The 9 V battery-operated device was <0.05 mT with a low-frequency coil of 2 kHz plus harmonics up to 50 kHz modulated on a 3, 7.8, or 20 Hz base frequency and an ultrahigh frequency coil with a 250 MHz modulated frequency plus harmonics of the same modulation as the LF coil. Patients were instructed to use the magnetic devices three times a day. The 7.8 Hz modulation frequency was prescribed for the morning and afternoon treatments, while the 3 Hz modulation frequency was prescribed for the evening. Baseline assessments showed that the treatment groups were equally matched. Analysis at follow-up showed greater between group improvements in global scores of health status. Paired analysis showed significant improvements in the actively treated group in objective function, pain, disability, and quality of life at study end compared to baseline. These differences were not seen in the placebo-treated group.


In another randomized, double-blind, placebo-controlled clinical trial of knee OA in Denmark (Thamsborg et al., 2005), 83 patients had two 2 h of daily treatment, 5 days per week for 6 weeks. They were reevaluated at 2 and 6 weeks after treatment. Again, objective standardized measures were used. There was a significant improvement in ADL, stiffness, and pain in the PEMF-treated group. In the control group, there was no effect on ADL after 2 weeks and a weak change in ADL after 6 and 12 weeks. Even the control group had significant reductions in pain at all evaluations and in stiffness after 6 and 12 weeks. There were no between-group differences in pain over time. ADL score improvements for the PEMF-treated group appeared to be less with increasing age. When groups were compared, those <65 years of age had significant reduction in stiffness. While this tended to be a negative study, when looking at between-group comparisons, there were indications of improvement in ADLs and stiffness, especially in individuals younger than 65.


Twenty-seven OA patients treated with PEMF in a tube-like coil device for 18 half-hour exposures over 1 month had an average improvement of 23%-61% compared to 2%-18% in the placebo group (Trock et al., 1993). They were evaluated at baseline, midpoint of therapy, end of treatment, and 1 month later. The active treatment group had decreased pain and improved functional performance. Another study reported by the same group (Trock et al., 1994), including 86 patients with OA of the knee and cervical spine, showed significant changes from baseline for the treated patients at the end of treatment and at 1-month follow-up. Placebo patients also showed improvement but with less statistical significance at the end of treatment and had lost significance for most variables at 1-month follow-up. The study patients showed improvements in pain, pain on motion, patient overall assessment, and physician global assessment.


One study (Sutbeyaz et al., 2006) looked at the effect of PEMFs on pain, ROM, and functional status in patients with cervical osteoarthritis (COA). Thirty-four patients were included in a randomized double-blind study. PEMF was administrated to the whole body using a 1.8×0.6 m size whole body mat. They were on the mat for 30 min per session, twice a day for 3 weeks. Pain levels in the PEMF treatment group decreased significantly after therapy (p<0.001), with no change in the sham group. Active ROM, neck muscle spasm, and disability (NPDS) scores also improved significantly after PEMF therapy (p<0.001). No change was seen in the sham group. This study shows that PEMFs can give significant pain reduction in neck arthritis and can be used alone or with other therapies to give even greater benefits.


A 50 Hz pulsed sinusoidal MF, 35 mT field PEMF for 15 min, 15 treatment sessions, improves hip arthritis pain in 86% of patients. Average mobility without pain improved markedly (Rehacek et al., 1982). Forty-seven patients with periarthritis of the shoulder who were receiving outpatient physical therapy were randomized using a controlled triple-blind study design to conventional physical therapy or conventional physical therapy with pulsed MF therapy (Leclaire and Bourgouin, 1991). They received treatments three times a week for a maximum of 3 months. PEMF therapy was applied 30 min at a time at three different frequencies 10/15/30 Hz with matched intensities of 3/4/6 mT over the course of the therapy program. This study showed no statistically significant benefit from magnetotherapy in the pain score, ROM, or improvement of functional status in patients with periarthritis of the shoulder. There appeared to be a trend toward slightly worse baseline function of the magnetic therapy group. This would therefore suggest that treatment was not carried out for a sufficient time. An improvement in the design of the study would have been to follow the individuals until they had achieved either goal recovery or full recovery, as would happen in clinical practice. Another possibility for the lack of benefit for the pulsed magnetic therapy group is that the frequencies and intensities used are not optimized for this particular condition, given the length and the frequency of treatments per week.


Fibromyalgia (FM) is a complex syndrome, primarily affecting women. PEMFs can frequently be very helpful. In one study (Sutbeyaz et al., 2009), 56 women with FM, aged 18-60 years, were randomly assigned to either PEMF or sham therapy, 30 min per session, twice a day for 3 weeks. Treatment outcomes were assessed after treatment and at 4 weeks, showing significant improvements in test scores at the end of therapy and at 4-week follow-up. The sham group also showed improvement at this time on all outcome measures except the specific FM questionnaire. So, low-frequency PEMF therapy can improve at least some general FM symptoms. A low-intensity PEMF (400 μT) in a portable device fitted to their head was found to help FM. In a randomized, double-blind, sham-controlled clinical trial (Thomas et al., 2007), patients with either chronic generalized pain from FM (n=17) or chronic localized musculoskeletal or inflammatory pain (n=15) were exposed in treatments twice daily for 40 min over 7 days. A VAS scale was used. There was a positive difference with PEMF over sham treatment with FM, although not quite reaching statistical significance (p=0.06). The same level of benefit was not seen in those without FM. In patients with other causes of chronic, nonmalignant pain, either longer periods of exposure are necessary or other approaches need to be considered.


The effect of specific PEMF exposure on pain and anxiety ratings was investigated in two patient populations (Shupak et al., 2006). A double-blind, randomized, placebo-controlled parallel design was used on the effects of an acute 30 min MF exposure (less than or equal to 400 μT; less than 3 kHz) on VAS-assessed pain and anxiety ratings in female RA and FM patients who received either the PEMF or sham exposure treatment. A significant pre-post effect was present for the FM patients, p<0.01. There was no significant reduction in VAS anxiety ratings pre-to-post-exposure.


An in vivo study of PEMFs (Shafford H L, et al. 2002) was done in dogs postoperatively after ablation of ovaries and uterus to see how pain is affected and interacts with postoperative morphine analgesia. Sixteen healthy dogs were examined within 6 h postoperation at eight different time points. There were four groups: (1) control group (NaCl administration), (2) postoperative PEMF exposure (NaCl administration), (3) postoperative morphine application, and (4) postoperative morphine application plus PEMF exposure. The PEMF was 0.5 Hz, exposure intermittent, 20 min field on/20 min field off for 6 h, whole-body exposure. At 30 min, the total pain score for group 4 was significantly less than for the control group, but not significantly different from group 2 or 3. The results suggest that PEMF may augment morphine analgesia or be used separately postoperatively after invasive abdominal procedures.


After breast augmentation surgery, patients (Hedén and Pilla, 2008) applied a portable and disposable noninvasive, high-frequency and low-intensity PEMF device in a double-blind, randomized, placebo-controlled study. Healthy females undergoing breast augmentation for aesthetic reasons were separated into three cohorts: (n=14) receiving bilateral PEMF treatment, (n=14) receiving bilateral sham devices, and (n=14) an active device to one breast and a sham device to the other breast. Pain levels were measured twice daily through the seventh day after surgery (POD 7), and postoperative analgesic use was also tracked. VAS scores decreased in the active cohort by almost three times the sham cohort by POD 3 (p<0.001) and persisted at this level to POD 7. Postoperative pain medication use decreased nearly three times faster in the active versus the sham cohorts by POD 3 (p<0.001). These results can be extended to include the use of this form of PEMF for the control of almost any situation of postoperative pain, especially involving surgery on superficial physical structures.


In another surgical study, this time post breast reduction for symptomatic macromastia, PEMFs were studied, not only on their results on postoperative pain, but also on potential mechanisms, including changes to cytokines and angiogenic factors in the wound bed (Rodhe et al., 2010). Twenty-four patients were randomized in a double-blind, placebo-controlled, randomized fashion to a sham control or a low-intensity 27.12 Hz PEMF configured to modulate the calmodulin-dependent nitric oxide signaling pathway. Pain levels were measured by VAS, and narcotic use was recorded. The PEMF used produced a 57% decrease in mean pain scores at 1 h (p<0.01) and a 300% decrease at 5 h (p<0.001), persisting to 48 h postoperatively in the active versus the control group, along with a concomitant 2.2-fold reduction in narcotic use in active patients (p=0.002). Mean IL-1β in wound exudates was 275% lower (p<0.001), suggesting fairly rapid reductions in acute posttraumatic inflammation.


On the other hand, some research has found a lack of benefit of PEMFs postoperatively. Pain after elective inguinal hernia repair was evaluated in a double-blind randomized, non-PEMF controlled trial using a high-frequency low-intensity portable PEMF device (Reed et al., 1987). The device had an output rate of 320 Hz, pulse width of 60 μs, and maximum power output of 1 W. Treatment was 15 min twice a day, over and under the thigh. VAS at 24 and 48 h postoperatively showed no difference between treated and untreated groups. This study most likely used treatment times that were too short for the intensities used, and the electrodes were placed remote to the actual wound, not over the surgical site.


Severe joint inflammation following trauma, arthroscopic surgery, or infection can damage articular cartilage; thus, every effort should be made to protect cartilage from the catabolic effects of proinflammatory cytokines and stimulate cartilage anabolic activities. A pilot, randomized, prospective, and double-blind study (Zorzi et al., 2007) was done to evaluate the effects of PEMFs (75 Hz, rectangular) after arthroscopic treatment of knee cartilage. Patients with knee pain were recruited and treated by arthroscopy with chondroabrasion and/or perforations and/or radio frequencies. There were two groups: lower-intensity control (MF at 0.05 mT) and active (MF of 1.5 mT). PEMFs were used for 90 days, 6 h per day. Objective measures were used before arthroscopy, and after 45 and 90 days, the use of anti-inflammatories (NSAIDs) was recorded. Three-year follow-up interviews were also used (n=31). Knee score values at 45 and 90 days were higher in the active group at 90 days (p<0.05). NSAID use was 26% in the active group and 75% in the control group (p=0.015). At 3-year follow-up, the percent completely recovered was higher in the active group (p<0.05).


Anterior cruciate ligament reconstruction, now a common surgical procedure, is usually performed by a minimally invasive arthroscopic approach. Even so, arthroscopy may elicit an inflammatory joint reaction detrimental to articular cartilage. PEMFs would be expected to mitigate some of these inflammation reactions. To study this possibility, a prospective, randomized, and double-blind study was done on 69 patients with a 75 Hz, 1.5 mT device, 4 h per day for 60 days versus sham device (Benazzo et al., 2008). At follow-up, active treatment patients showed a statistically significant faster recovery (p<0.05). The use of anti-inflammatories was less frequent (p<0.05). Joint swelling and return to normal ROM occurred faster (p<0.05). The 2-year follow-up did not show statistically significant difference between the two groups. In addition, a subset analysis of 29 patients (15 in the active group; 14 in the placebo group) who concurrently had meniscectomy, function scores between the two groups were even larger than observed in the whole study. So, this particular PEMF signal is expected to shorten postoperative recovery time and limit joint inflammation.


Noninflammatory chronic pelvic pain syndrome (CPPS) can be quite disabling in both men and women, frequently with no adequate treatment options. A study (Leippold et al., 2005) was designed to prospectively evaluate sacral magnetic stimulation as a treatment option for patients with noninflammatory CPPS (CPPS, category IIIB). Fourteen men were treated with sacral magnetic stimulation, 10 treatment sessions once a week for 30 min at a frequency of 50 Hz. Twelve of fourteen men reported improvement but only during the time of stimulation. Inventory scores before and after treatment did not change. There was no sustained effect beyond the time of stimulation on the mean scores for pain, micturition complaints, or quality of life. Sacral magnetic stimulation in patients with CPPS IIIB reduces pain only during stimulation. The fact the pain relief is obtained during treatment is notable and valuable. Because this level of frequency of treatments is less likely to induce healing in the tissues causing the pain syndrome, it may be reasonable to expect only a reduction in pain during the treatment course and not a more enduring benefit. While this treatment approach does not appear to be useful, it remains to be seen whether a change in the protocol may produce more enduring results.


Gynecologic pelvic pain may also benefit from PEMFs. A high-voltage, high intensity, pulsed stimulation (1-30 pulses/second) system (Jorgensen et al., 1994) was used in the setting of ruptured ovarian cysts, postoperative pelvic hematomas, chronic urinary tract infection, uterine fibrosis, dyspareunia, endometriosis, and dysmenorrhea. Ninety percent of patients experienced marked rapid relief from pain, with pain subsiding within 1-3 days after PEMF treatment, eliminating supplementary analgesics.


In dentistry, periodontal disease may cause bone resorption severe enough to require bone grafting. Grafting is followed by moderate pain peaking several hours afterward. Repeated PEMF exposure for 2 weeks eliminates pain within a week. Even single PEMF exposure to the face for 30 min of a 5 mT field and related conservative treatment produce much lower pain scores versus controls (Tesic et al., 1999).


Results of PRF PEMF in a case series either eliminates or improves, even at 2 weeks following therapy, pain in 80% of patients with pelvic inflammatory disease, 89% with back pain, 40% with endometriosis, 80% with postoperative pain, and 83% with lower abdominal pain of unknown cause (Punnonen et al., 1980).


PEMFs have been found to be helpful in headaches. For migraine headaches, high-frequency (5361 gHz) PEMFs applied to specific acupuncture points on the inner thighs for at least 2 weeks are effective short-term therapy (Sherman et al., 1999). Longer exposures lead to greater reduction of headache activity. One month after a treatment course, 73% of patients report decreased headache activity versus 50% of placebo treatment. Another 2 weeks of treatment after the 1-month follow-up gives an additional 88% decrease in headache activity. Patients with headache treated with a PEMF for 15 days after failing acupuncture and medications get effective relief of migraine, tension, and cervical headaches at about 1 month after treatment (Prusinski et al., 1987). They have at least a 50% reduction in frequency or intensity of the headaches and reduction in analgesic drug use. Cluster and posttraumatic headaches do not respond as well.


PEMFs of various kinds, strengths, and frequencies included have been found to have good results in a wide array of painful conditions. There is little risk when compared to the potential invasiveness of other therapies and the risk of toxicity, addiction, and complications from medications. This creates an ideal setup for clinicians to attempt PEMFs before other more potentially harmful treatments are attempted, especially for long-term treatment of chronic pain conditions.


REFERENCES



  • Aktas I, Akgun K, Cakmak B. (August 2007) Therapeutic effect of pulsed electromagnetic field in conservative treatment of subacromial impingement syndrome. Clin Rheumatol 26(8): 1234-1239.

  • Aleman A. (August 2013) Use of repetitive transcranial magnetic stimulation for treatment in psychiatry. Clin Psychopharmacol Neurosci 11(2): 53-59.

  • Alvarez, O. M., Mertz, P. M. Smerbeck, R. V. and Eaglstein, W. H. The Healing of Superficial Skin Wounds is Stimulated by External Electrical Current. J. Invest. Dermatol. 81, 144-148 (1983).

  • Arnold M D, Thornbrough L M. (August 1999) Treatment of musculoskeletal pain with traditional Chinese herbal medicine. Phys Med Rehabil Clin N Am 10(3): 663-671, ix-x.

  • Assimacopoulos, D. Low Intensity Negative Electric Current in the Treatment of Ulcers of the Leg Due to Chronic Veinous Insufficiency. Am. J. Surg. 115, 683-687 (1968).

  • Assimacopoulos, D. Wound Healing Promotion by the Use of Negative Electric Current, Am. Surg. 34, 423-431 (1968).

  • Athenstaedt, H. Permanent Electric Polarization of the Meninges of Man, Z. Zellforsh 98, 300-322 (1969).

  • Ay S, Evcik D. (April 2009) The effects of pulsed electromagnetic fields in the treatment of knee osteoarthritis: A randomized, placebo-controlled trial. Rheumatol Int 29(6): 663-666.

  • Barker, A. T., The Design of a Clinical Electro-Magnetic Bone Stimulator, Clinical Physical Physiology Measurement, February, 1981, Volume II, No. 1, Pages 9-16.

  • Bassett C, Schink-Ascani M. Long-term pulsed electromagnetic field (PEMF) results in congenital pseudarthrosis. Calcified Tissue International. 1991; 49(3):216-20.

  • Bassett, C. A. L. Biophysical Principles Affecting Bone Structure, in: The Biochemistry and Physiology of Bone, Vol. II, Bourne, G. H., Ed., Academic Press, New York, 1971, 1.

  • Bassett, C. A. L. The Development and Application of Pulsed Electromagnetic Fields (PEMFs) for Ununited Fractures and Arthrodeses. Orthoped. Clinics of North Am. 15, 61-87 (1984).

  • Bassett, C. A. L., Mitchell, S. N. and Gaston, S. R. Treatment of Ununited Tibial Diaphyseal Fractures with Pulsing Electromagnetic Fields, J. Bone Jt. Surg. 63-A, 511-523 (1981).

  • Behrens B, Michlovitz S. Physical Agents Theory and Practice. Second ed. Philadelphia: F. A. Davis; 2006. p. 145

  • Benazzo F, Zanon G, Pederzini L et al. (June 2008) Effects of biophysical stimulation in patients undergoing arthroscopic reconstruction of anterior cruciate ligament: Prospective, randomized and double blind study. Knee Surg Sports Traumatol Arthrosc 16(6): 595-601.

  • Binder A, Parr G, Hazleman B, Fitton-Jackson S. Pulsed Electromagnetic Field Therapy Of Persistent Rotator Cuff Tendinitis: A Double-blind Controlled Assessment. The Lancet. 1984; 323(8379):695-8.

  • Borg M J, Marcuccio F, Poerio A M et al. (October 1996) Magnetic fields in physical therapy. Experience in orthopedics and traumatology rehabilitation. Minerva Med 87(10): 495-497.

  • Brighton, C. T., Adler, S., Black, J., Itada, N., Friedenberg, Z. B. Cathodic oxygen consumption and electrically induced osteogenesis. Clin. Orth. Rel. Res. 107, 277-282 (1975).

  • Brighton, C. T., Black, J., Friedenberg, Z. B., Esterhai, J. L. Day, L. J. and Connolly, J. F. A Multicenter Study of the Treatment of Non-union with Constant Direct Current, J. Bone Jt. Surg. 63-A, 2-13 (1981).

  • Carey, L. C. and Lepley, L. D. Effect of Continuous Direct Electric Current on Healing Wounds. Surg. Forum 13, 33-36 (1962).

  • Carley, P. J. and Wainapel, S. F. Electrotherapy for Acceleration of Wound Healing: Low Intensity Direct Current. Arch. Phys. Med. Rehab. 66, 443-446 (1985).

  • Caselli M A, Clark N, Lazarus S, Velez Z et al. (January 1997) Evaluation of magnetic foil and PPT insoles in the treatment of heel pain. J Am Podiatr Med Assoc 87(1): 11-16.

  • Chang W H-S, Chen L-T, Sun J-S, Lin F-H. Effect of pulse-burst electromagnetic field stimulation on osteoblast cell activities. Bioelectromagnetics. 2004; 25(6):457-65.

  • Cheing G L, Wan J W, Kai Lo S. (November 2005) Ice and pulsed electromagnetic field to reduce pain and swelling after distal radius fractures. J Rehabil Med 37(6): 372-377.

  • Cheng, N., VanHoof, H., Brockx, E., Hoogmartens, M. J., Mulier, J. C., DeDijcker, F. J. Sansen, W. M. and DeLoecker, W. The effects of electric currents on ATP generation, protein synthesis and membrane transport in rat skin. Clin. Orth. Rel. Res. 171, 264-572 (1982).

  • Cieslar G, Mrowiec J, Sieron A et al. (1994) The reactivity to thermal pain stimulus in rats exposed to variable magnetic field. Balneol Pol 36(3-4): 24-28.

  • Cieslar G, Sieron A, Radelli J. (1995) The estimation of therapeutic effect of variable magnetic fields in patients with diabetic neuropathy including vibratory sensibility. Balneol Pol 37(1): 23-27.

  • Colbert A P, Cleaver J, Brown K A et al. (September 2008) Magnets applied to acupuncture points as therapy—A literature review. Acupunct Med 26(3): 160-170.

  • Colbert A P, Markov M S, Banerji M et al. (1999) Magnetic mattress pad use in patients with fibromyalgia: A randomized double-blind pilot study. J Back Musculoskelet Rehabil 13: 19-31.

  • Colloca L, Klinger R, Flor H et al. (April 2013) Placebo analgesia: Psychological and neurobiological mecha-nisms. Pain 154(4): 511-514.

  • Covall D J, Wasilewski S A. (1992) Roentgenographic changes after arthroscopic meniscectomy: Five-year follow-up in patients more than 45 years old. Arthroscopy 8(2): 242-246.

  • De Loecker W, Cheng N, Delport P H. Effects of pulsed electromagnetic fields on membrane transport. In Emerging Electromagnetic Medicine. Ed's: O'Connor M E, Bentall, R H C, Monahan, J C. New York: Springer-Verlag, 1990, pp. 45-59.

  • DeHaas, W. G., Watson, J. and Morrison, D. M. Non-Invasive Treatment of Ununited Fractures of the Tibia Using Electrical Stimulation. J. Bone. Jt. Surg. 62-B, 465-470 (1980).

  • Del Seppia C, Ghione S, Luschi P et al. (2007) Pain perception and electromagnetic fields. Neurosci Biobehav Rev 31(4): 619-642.

  • Delle Monache S, Alessandro R, Iorio R, Gualtieri G, Colonna R. Extremely low frequency electromagnetic fields (ELF-EMFs) induce in vitro angiogenesis process in human endothelial cells. Bioelectromagnetics. 2008; 29(8):640-8.

  • Devereaux M D, Hazleman B L, Thomas P P. (October-December 1985) Chronic lateral humeral epicondylitis—A double-blind controlled assessment of pulsed electromagnetic field therapy. Clin Exp Rheumatol 3(4): 333-336.

  • Di Massa A, Misuriello I, Olivieri M C et al. (1989) Pulsed magnetic fields. Observations in 353 patients suffer-ing from chronic pain. Minerva Anestesiol 55(7-8): 295-299.

  • Doillon, C. J. and Silver, F. H. Collagen Wound Dressing: Effect of Hyaluronic Acid and Fibronectin, Biomaterials 7, 3-8 (1986).

  • Doillon, C. J., Dunn, M. G., Berg, R. A. and Silver, F. H. Collagen Deposition During Wound Repair. Scanning Electron Microscopy, 11, 897-903 (1985).

  • Doillon, C. J., Whyne, C. F., and Berg, R. A. Fibroblast Growth on a Porous Collagen Sponge Containing Hyaluronic Acid and Fibronectin, Biomaterials 8, 195-200 (1987).

  • Doillon, C. J., Whyne, C. F., Berg, R. A., Olson, R. M. and Silver, F. H. Fibroblast-Collagen Sponge Interactions and the Spatial Deposition of Newly Formed Collagen Fibers In Vitro and In Vivo, Scanning Electron Microscopy III, 1313-1320 (1984).

  • Doillon, C. J., Whyne, C. F., Brandwein, S. and Silver, F. H. Collagen-Based Wound Dressings: Control of the Pore Structure and Morphology. J. Biomed. Mater. Res. 20, 1219-1228 (1986).

  • Ellis W V. (1993) Pain control using high-intensity pulsed magnetic stimulation. Bioelectromagnetics 14(6): 553-556.

  • Eriksen W, Sandvik L, Bruusgaard D. (October 1996) Does dietary supplementation of cod liver oil mitigate musculoskeletal pain? Eur J Clin Nutr 50(10): 689-693.

  • Farndale R, Murray J. Pulsed electromagnetic fields promote collagen production in bone marrow fibroblasts via athermal mechanisms. Calcified Tissue International. 1985; 37(2):178-82.

  • Fernandez M I, Watson P J, Rowbotham D J. (August 2007) Effect of pulsed magnetic field therapy on pain reported by human volunteers in a laboratory model of acute pain. Br J Anaesth 99(2): 266-269.

  • Fischer G. (2002) Relieving pain in diseases of the musculoskeletal system with small apparatuses that produce magnetic fields, Personal communication.

  • Fleming J L, Persinger M A, Koren S A. (1994) Magnetic pulses elevate nociceptive thresholds: Comparisons with opiate receptor compounds in normal and seizure-induced brain-damaged rats. Electro Magnetobiol. 13(1): 67-75.

  • Foley-Nolan D, Barry C, Coughlan R J et al. (1990) Pulsed high frequency (27 MHz) electromagnetic therapy for persistent neck pain. A double blind, placebo-controlled study of 20 patients. Orthopedics 13(4):445-451.

  • Foley-Nolan D, Moore K, Codd M et al. (1992) Low energy high frequency pulsed electromagnetic therapy for acute whiplash injuries. A double blind randomized controlled study. Scand J Rehabil Med 24(1): 51-59.

  • Forestier R, Francon A, Saint Arroman F et al. (April 2007b) Are SPA therapy and pulsed electromagnetic field therapy effective for chronic neck pain? Randomised clinical trial. Second part: Medicoeconomic approach. Ann Readapt Med Phys 50(3): 148-153.

  • Forestier R, Francon A, Saint-Arromand F et al. (April 2007a) Are SPA therapy and pulsed electromagnetic field therapy effective for chronic neck pain? Randomised clinical trial. First part: Clinical evaluation. Ann Readapt Med Phys 50(3): 140-147.

  • Frank, C. B., and Szeto, A. Y. J. A Review of Electromagnetically Enhanced Soft Tissue Healing. IEEE Engineering in Medicine and Biology Magazine 27-32 (December 1983).

  • Friedenberg, Z., Andrews, E. T. Smolenski, B. I. Pearl, B. W. and Brighton, C. T. Bone Reaction to Various Amounts of Direct Current. Surg. Gyn. Obstet. 131, 894-899 (1970).

  • Fukada, E. Piezoelastic Properties of Biological Macromolecules, Advances Biophys 6, 121-155 (1974).

  • Ganesan K, Gengadharan A C, Balachandran C, Manohar B M, Puvanakrishnan R. Low frequency pulsed electromagnetic field—a viable alternative therapy for arthritis. Indian J Exp Biol. 2009; 47(12):939-48.

  • Gault, W. R. and Gatens, P. F. Use of Low Intensity Direct Current in Management of Ischemic Skin Ulcers. Phys. Ther. 56, 265-269 (1976).

  • Gensler, W. Electrochemical Healing Similarities Between Animals and Plants. Biophys. J. 27, 461-466 (1979).

  • Gómez-Ochoa I, Gómez-Ochoa P, Gómez-Casal F, Cativiela E, Larrad-Mur L. Pulsed electromagnetic fields decrease proinflammatory cytokine secretion (IL-1β and TNF-α) on human fibroblast-like cell culture. Rheumatology International. 2011; 31(10):1283-9.

  • Goodman, R., Basset, C. A. L., and Henderson, A. S. Pulsing Electromagnetic Fields Induce Cellular Transcription. Science 220, 1283-1285 (1983).

  • Gordon G A. Designed electromagnetic pulsed therapy: Clinical applications. Journal of Cellular Physiology. 2007; 212(3):579-82.

  • Graak V, Chaudhary S, Bal B S et al. (April 2009) Evaluation of the efficacy of pulsed electromagnetic field in the management of patients with diabetic polyneuropathy. Int J Diabetes Dev Ctries 29(2): 56-61.

  • Grodzinsky, A. J. Electromechanical and Physiochemical Properties of Connective Tissue, CRC Critical Reviews in Biomedical Engineering 9, 133-199 (1983).

  • Guseo A. Physiological effects of pulsing electromagnetic field. In First Congress of European Bioelectromagnetics Association (EBEA), Brussels, Belgium, January 1992, s.31.

  • Haldeman S, Rubinstein S M. (January 1993) The precipitation or aggravation of musculoskeletal pain in patients receiving spinal manipulative therapy. J Manipulat Physiol Ther 16(1): 47-50.

  • Han T R, Shin H I, Kim I S. (July 2006) Magnetic stimulation of the quadriceps femoris muscle: Comparison of pain with electrical stimulation. Am J Phys Med Rehabil 85(7): 593-599.

  • Harlow T, Greaves C, White A, Brown L, Hart A, Ernst E. (2004) Randomised controlled trial of magnetic bracelets for relieving pain in osteoarthritis of the hip and knee. BMJ 329: 1450-1454.

  • Hedén P, Pilla A A. (July 2008) Effects of pulsed electromagnetic fields on postoperative pain: A double-blind randomized pilot study in breast augmentation patients. Aesthetic Plast Surg 32(4): 660-666.

  • Huang L Q, He H C, He C Q, Chen J, Yang L. Clinical update of pulsed electromagnetic fields on osteoporosis. Chin Med J. 2008; 121(20):2095-9.

  • ICNIRP (2010) Guidelines for limiting exposure to time-varying electric and magnetic fields (1 Hz-100 kHz). Health Phys 99(6): 818-836.

  • Institute of Medicine (TOM) of the National Academies. Complementary and Alternative Medicine in the United States. Washington, D.C.: The National Academies Press, 2005, p. 1.

  • Jerabek J, Pawluk W. Magnetic Therapy in Eastern Europe: A Review of 30 Years of Research. Chicago, Ill.: Advanced Magnetic Research of the Delaware Valley, 1996.

  • Jorgensen W A, Frome B M, Wallach C. (1994) Electrochemical therapy of pelvic pain: Effects of pulsed elec-tromagnetic fields (PEMF) on tissue trauma. Eur J Surg 160(574 Suppl): 83-86.

  • Junquiera, L. C. U., Bignolas G. and Bretani, R. R. Picro-Sirius Staining Plus Polarization Microscopy, A Specific Method for Collagen Detection in Tissue Sections. Histochem. J. 11, 477-455 (1979).

  • Kennedy W F, Roberts C G, Zuege R C, Dicus W T. Use of pulsed electromagnetic fields in treatment of loosened cemented hip prostheses. A double-blind trial. Clin Orthop Relat Res. 1993; 286(286):198-205.

  • Khamaganova I V, Boinich Z V, Arutiunova E S. (1993) Clinical aspects of the use of a pulsed magnetic field. Fizicheskaia Meditzina 3(1-2): 35-37.

  • Kholodov Y A. A non-specific initial response of brain to various electromagnetic fields. In International Meeting of Electromagnetic Fields: Biological Effects and Hygienic Standards, Moscow, Russia, May 1998.

  • Kjellman G V, Skargren E I, Oberg B E. (1999) A critical analysis of randomised clinical trials on neck pain and treatment efficacy. A review of the literature. Scand J Rehabil Med 31(3): 139-152.

  • Komanowsky, M. Production of Comminuted Collagen for Novel Applications. J. Am. Leather Chem., 69, 410-411 (1974).

  • Konikoff, J. J. Electrical Promotion of Soft Tissue Repairs. Ann. Biomed. Engng. 4, 1-5 (1976).

  • Kumar V. Chapter 1: Cell injury, cell death and adaptations. In Robbins and Cotran Pathologic Basis of Disease, Professional Edition Philadelphia, Elsevier. 8th edn., 2007. Vinay Kumar, MBBS, M D, FRCPath, Abul K. Abbas, MBBS and Jon C. Aster, M D, PhD

  • Kusaka C, Seto A, Nagata T et al. (1995) Pulse magnetic treatment and whole-body, alternating current magnetic treatment for post-herpetic neuralgia. J Jpn Biomagnet Bioelectromagnet Soc 8(2): 29-38.

  • Lavine, L. S., Lustrin, I., Shomos, M. H., Rinaldi, R. A. and Liboff, A. R. Electric Enhancement of Bone Healing, Science 175, 1118-1121 (1972).

  • Leaper, D. J., Foster, M. E., Brennan, S. S. and Davies, P. W. An Experimental Study of the Influence of Magnetic Fields on Soft-Tissue Wound Healing. J. of Trauma 25, 1083-1084 (1985).

  • Leclaire R, Bourgouin J. (April 1991) Electromagnetic treatment of shoulder periarthritis: A randomized controlled trial of the efficiency and tolerance of magnetotherapy. Arch Phys Med Rehabil 72(5): 284-287.

  • Lefaucheur J P, Drouot X, Menard-Lefaucheur I et al. (April 2004) Neurogenic pain relief by repetitive transcranial magnetic cortical stimulation depends on the origin and the site of pain. J Neurol Neurosurg Psychiatr 75(4): 612-616.

  • Leippold T, Strebel R T, Huwyler M et al. (2005) Sacral magnetic stimulation in noninflammatory chronic pelvic pain syndrome. BJU Int 95: 838-841.

  • Levy R, Deer T R, Henderson J. (March-April 2010) Intracranial neurostimulation for pain control: A review. Pain Phys 13(2): 157-165.

  • Lin M L, Lin M H, Fen J J et al. (2010) A comparison between pulsed radiofrequency and electro-acupuncture for relieving pain in patients with chronic low back pain. Acupunct Electrother Res 35(3-4): 133-146.

  • Marino, A. A. and Becker, R. O. The Effect of Electric Current on Rat Tail Tendon Collagen in Solution, Calc. Tiss. Res. 4, 330-338 (1970).

  • Markov M. Pulsed electromagnetic field therapy history, state of the art and future. The Environmentalist. 2007; 27(4):465-75.

  • Markov M S, Pilla A A. (1995) Electromagnetic field stimulation of soft tissue: Pulsed radiofrequency treatment of post-operative pain and edema. Wounds 7(4): 143-151.

  • Markov M S. Magnetic and electromagnetic field therapy: Basic principles of application for pain relief. In Bioelectromagnetic Medicine. Ed's: Rosch, P J and Markov, M S. New York, Marcel Dekker, 2004, pp. 251-264.

  • Mattei M D, Caruso A, Pezzetti F, Pellati A, Stabellini G, Sollazzo V, et al. Effects of Pulsed Electromagnetic Fields on Human Articular Chondrocyte Proliferation. Connective Tissue Research. 2001; 42(4):269-79.

  • McLeod, K. J., Lee, R. C. and Ehrlich, H. P. Frequency Dependence of Electric Field Modulation of Fibroblast Protein Synthesis, Science 236, 1465-1468 (1987).

  • Mitbreit I M, Savchenko A G, Volkova L P et al. (1986) Low-frequency magnetic field in the complex treatment of patients with lumbar osteochondrosis. Ortop Travmatol Protez-10: 24-27.

  • Murray, J. C. and Farndale, R. W. Modulation of Collagen Production in Cultured Fibroblasts by a Low-Frequency, Pulsed Magnetic Field. Biochem. Biophys. Acta 838, 98-105 (1985).

  • Nelson F R, Zvirbulis R, Pilla A A. (August 2013) Non-invasive electromagnetic field therapy produces rapid and substantial pain reduction in early knee osteoarthritis: A randomized double-blind pilot study. Rheumatol Int 33(8): 2169-2173.

  • Panagopoulos D J, Karabarbounis A, Margaritis L H. Mechanism for action of electromagnetic fields on cells. Biochemical and Biophysical Research Communications. 2002; 298(1):95-102.

  • Pawluk W, Turk Z, Fischer G, Kobinger W. Treatment of osteoarthritis with a new broadband PEMF signal. Presentation. 24th Annual Meeting of Bioelectromagnetics Society, Quebec City, Quebec, Canada, June 2002.

  • Pawluk, William, Magnetic Fields for Pain Control, Ch. 17 In Electromagnetic Fields in Biology and Medicine, CRC Press, publication January 2015. Marko S. Markov, Ed.

  • Pennington G M, Danley D L, Sumko M H et al. (February 1993) Pulsed, non-thermal, high-frequency electro-magnetic energy (DIAPULSE) in the treatment of grade I and grade II ankle sprains. MilMed 158(2): 101-104.

  • Picarelli H, Teixeira M J, de Andrade D C et al. (November 2010) Repetitive transcranial magnetic stimulation is efficacious as an add-on to pharmacological therapy in complex regional pain syndrome (CRPS) type I. J Pain 11(11): 1203-1210.

  • Pilla A A. (June 2013) Nonthermal electromagnetic fields: From first messenger to therapeutic applications. Electromagnet Biol Med 32(2): 123-136.

  • Pilla A A. Electromagnetic therapeutics: State-of-the-art in hard and soft tissue applications. Presentation. Fourth International Congress of European Bioelectromagnetics Assoc. (EBEA), Zagreb, Croatia, November 1998.

  • Pipitone N, Scott D L. (2001) Magnetic pulse treatment for knee osteoarthritis: A randomised, double-blind, placebo-controlled study. Curr Med Res Opin 17(3): 190-196.

  • Pleger B, Janssen F, Schwenkreis P et al. (Feb. 12, 2004) Repetitive transcranial magnetic stimulation of the motor cortex attenuates pain perception in complex regional pain syndrome type I. Neurosci Lett 356(2): 87-90.

  • Prato F S, Del Seppia C, Kavaliers M et al. Stress-induced analgesia in house mice and deer mice is reduced by application of various magnetic fields conditions. 21st Annual Meeting of Bioelectromagnetics Society, Long Beach, Calif., June 1999. Abstract 6-3:38

  • Prato F S, Thomas A W, Cook C M. (2001) Human standing balance is affected by exposure to pulsed ELF magnetic fields: Light intensity-dependent effects. Neuroreport 12(7): 1501-1505.

  • Preszler R R. A non-invasive complementary method of reducing chronic muscular low back pain using permanent magnetic therapy. Master thesis, Physician Assistant Studies, University of Nebraska School of Medicine, Physician Assistant Program, Lincoln, Omaha, Nebr., 2000.

  • Prusinski A, Wielka J, Durko A. (1987) Pulsating electromagnetic field in the therapy of headache. In Second Symposium on Magnetotherapy, Szekesfehervar, Hungary, May 1987. J Bioelectr 7(1): 127-128.

  • Pujol J, Pascual-Leone A, Dolz C et al. (1998) The effect of repetitive magnetic stimulation on localized musculoskeletal pain. Neuroreport 9(8): 1745-1748.

  • Punnonen R, Gronroos M, Luikko P et al. (1980) The use of pulsed high-frequency therapy (Curapuls) in gynecology and obstetrics. Acta Obstet Gynecol Scand 59(2): 187-188.

  • Randall C, Randall H, Dobbs F et al. (June 2000) Randomized controlled trial of nettle sting for treatment of base-of-thumb pain. J Royal Soc Med 93(6): 305-309.

  • Rauscher E, Van Bise W L. Pulsed magnetic field treatment of chronic back pain. 23rd Annual Meeting of Bioelectromagnetics Society, St. Paul, Minn., June 2001. Abstract 6-3:38

  • Reed M W, Bickerstaff D R, Hayne C R, Wyman A, Davies J. (June 1987) Pain relief after inguinal herniorrhaphy. Ineffectiveness of pulsed electromagnetic energy. Br J Clin Pract 41(6): 782-784.

  • Rehacek J, Straub J, Benova H. (1982) The effect of magnetic fields on coxarthroses. Fysiatr Revmatol Vestn 60(2): 66-68.

  • Richards T L, Lappin M S, Acosta-Urquidi J, Kraft G H, Heide A C, Lawrie F W, et al. Double-blind study of pulsing magnetic field effects on multiple sclerosis. J Altern Complement Med. 1997; 3(1):21-9.

  • Robertson J A, Théberge J, Weller J et al. (Mar. 6, 2010) Low-frequency pulsed electromagnetic field exposure can alter neuroprocessing in humans. J Royal Soc Interface 7(44): 467-473.

  • Rohde C, Chiang A, Adipoju O et al. (June 2010) Effects of pulsed electromagnetic fields on interleukin-1 beta and postoperative pain: A double-blind, placebo-controlled, pilot study in breast reduction patients. Plast Reconstr Surg 125(6): 1620-1629.

  • Roos H, Laurén M, Adalberth T et al. (April 1998) Knee osteoarthritis after meniscectomy: Prevalence of radiographic changes after twenty-one years, compared with matched controls. Arthritis Rheumatol 41(4): 687-693.

  • Sandyk R. Role of the pineal gland in multiple sclerosis: a hypothesis. Journal of Alternative & Complementary Medicine. 1997; 3(3):267-90.

  • Sartucci F, Bonfiglio L, Del Seppia C et al. (1997) Changes in pain perception and pain-related somatosensory evoked potentials in humans produced by exposure to oscillating magnetic fields. Brain Res 769(2): 362-366.

  • Saveriano G, Ricci S. (April 1989) Experiences in treating secondary post-traumatic algodystrophy with low-frequency PEMFs in conjunction with functional rehabilitation. In International Symposium in Honor of Luigi Galvani, Bologna, Italy. J Bioelectr 8(2): 320.

  • Schauble, M. K., Habal, M. B., and Gullick, H. D. Inhibition of Experimental Tumor Growth in Hamsters by Small Direct Currents. Arch. Pathol. Lab. Med. 101, 294-297 (1977).

  • Schroter M. (March/April 1976) Conservative treatment of 240 patients with magnetic field therapy. Medizinisch-Orthopadische Technik 2:78.

  • Segal N A, Toda Y, Huston J et al. (2001) Two configurations of static magnetic fields for treating rheumatoid arthritis of the knee: A double-blind clinical trial. Arch Phys Med Rehabil 82(10): 1453-1460.

  • Shafford H L, Hellyer P W, Crump K T et al. (2002) Use of a pulsed electromagnetic field for treatment of postoperative pain in dogs: A pilot study. Vet Anaesth Analg 29(1): 43-48.

  • Sharrard W. A double-blind trial of pulsed electromagnetic fields for delayed union of tibial fractures. Journal of Bone & Joint Surgery, British Volume. 1990 May 1, 1990; 72-B(3):347-55.

  • Sherman R A, Acosta N M, Robson L. (1999) Treatment of migraine with pulsing electromagnetic fields: A double-blind, placebo-controlled study. Headache 39(8): 567-575.

  • Shupak N M, McKay J C, Nielson W R et al. (2006) Exposure to a specific pulsed low-frequency magnetic field: A double-blind placebo-controlled study of effects on pain ratings in rheumatoid arthritis and fibromyalgia patients. Pain Res Manage 11(2): 85-90.

  • Shupak N M, Prato F S, Thomas A W. (Jun. 10, 2004) Human exposure to a specific pulsed magnetic field: Effects on thermal sensory and pain thresholds. Neurosci Lett 363(2): 157-162.

  • Smith, J., Romansky, N., Vomero, J. and Davis, R. H. The Effect of Electrical Stimulation on Wound Healing in Diabetic Mice. J. Amer. Podiatry Assoc. 74, 71-75 (1984).

  • Spadaro, J. A. Electrically Stimulated Bone Growth in Animals and Man. Clinical Orthopeds. and Rel. Res. 122, 325-332 (1977).

  • Spadaro, J. A., Chase, S. E. and Webster, D. A. Bacterial Inhibition by Electrical Activation of Percutaneous Implants. J. Biomed. Mat. Res. 20, 565-577 (1986).

  • Stewart D J, Stewart J E. (1989) The destabilization of an abnormal physiological balanced situation, chronic musculoskeletal pain, utilizing magnetic biological device. Acta Med Hung 46(4): 323-337.

  • Stiller M J, Pak G H, Shupack J L, Thaler S, Kenny C, Jondreau L. A portable pulsed electromagnetic field (PEMF) device to enhance healing of recalcitrant venous ulcers: a double-blind, placebo-controlled clinical trial. British Journal of Dermatology. 1992; 127(2):147-54.

  • Sutbeyaz S T, Sezer N, Koseoglu B F. (February 2006) The effect of pulsed electromagnetic fields in the treatment of cervical osteoarthritis: A randomized, double-blind, sham-controlled trial. Rheumatol Int 26(4): 320-324.

  • Sutbeyaz S T, Sezer N, Koseoglu B F. The effect of pulsed electromagnetic fields in the treatment of cervical osteoarthritis: a randomized, double-blind, sham-controlled trial. Rheumatol Int. 2006; 26(4):320-4.

  • Sutbeyaz S T, Sezer N, Koseoglu F et al. (October 2009) Low-frequency pulsed electromagnetic field therapy in fibromyalgia: A randomized, double-blind, sham-controlled clinical study. Clin J Pain 25(8): 722-728.

  • Takeshige C, Sato M. (April-June 1996) Comparisons of pain relief mechanisms between needling to the muscle, static magnetic field, external qigong and needling to the acupuncture point. Acupunct Electrother Res 21(2): 119-131.

  • Taverner M, Loughnan T. (February 2014) Transcutaneous pulsed radiofrequency treatment for patients with shoulder pain booked for surgery: A double-blind, randomized controlled trial. Pain Pract 14(2):101-108.

  • Tesic D, Djuric M, Pekaric-Nadj N et al. PEMF aided pain reduction in stomatology. 21st Annual Meeting of Bioelectromagnetics Society, Long Beach, Calif., June 1999. Abstract P-141:157.

  • Thamsborg G, Florescu A, Oturai P et al. (July 2005) Treatment of knee osteoarthritis with pulsed electromagnetic fields: A randomized, double-blind, placebo-controlled study. Osteoarthr Cartil 13(7):575-581.

  • Thomas A W, Drost D J, Prato F S. (2001) Human subjects exposed to a specific pulsed (200 uT) magnetic field: Effects on normal standing balance. Neurosci Lett 297(2): 121-124.

  • Thomas A W, Graham K, Prato F S et al. (Winter 2007) A randomized, double-blind, placebo-controlled clinical trial using a low-frequency magnetic field in the treatment of musculoskeletal chronic pain. Pain Res Manage 12(4): 249-258.

  • Thomas A W, Prato F S. Magnetic field based pain therapeutics and diagnostics. Presentation. 24th Annual Meeting of Bioelectromagnetics Society, Quebec City, Quebec, Canada, June 2002.

  • Thomas A W, White K P, Drost D J et al. (Aug. 17, 2001) A comparison of rheumatoid arthritis and fibromyalgia patients and healthy controls exposed to a pulsed (200 microT) magnetic field: Effects on normal standing balance. Neurosci Lett 309(1): 17-20.

  • Thomas D, Collins S, Strauss S. (March 1992) Somatic sympathetic vasomotor changes documented by medical thermographic imaging during acupuncture analgesia. Clin Rheumatol 11(1): 55-59.

  • Thuile C, Walzl M. (2002) Evaluation of electromagnetic fields in the treatment of pain in patients with lumbar radiculopathy or the whiplash syndrome. Neuro Rehabil 17:63-67.

  • Trock D H, Bollet A J, Dyer R H Jr et al. (March 1993) A double-blind trial of the clinical effects of pulsed electromagnetic fields in osteoarthritis. J Rheumatol 20(3): 456-460.

  • Trock D H, Bollet A J, Markoll R. (1994) The effect of pulsed electromagnetic fields in the treatment of osteoarthritis of the knee and cervical spine. Report of randomized, double blind, placebo controlled trials. J Rheumatol 21(10): 1903-1911.

  • Trock D H. (February 2000) Electromagnetic fields and magnets. Investigational treatment for musculoskeletal disorders. Rheum Dis Clin N Am 26(1): 51-62, viii.

  • Ugawa Y, Terao Y, Hanajima R et al. (September 1997) Magnetic stimulation over the cerebellum in patients with ataxia. Electroencephalogr Clin Neurophysiol 104(5): 453-458.

  • Uzunca K, Birtane M, Taştekin N. (January 2007) Effectiveness of pulsed electromagnetic field therapy in lateral epicondylitis. Clin Rheumatol 26(1): 69-74.

  • Vallbona C, Richards T. (August 1999) Evolution of magnetic therapy from alternative to traditional medicine. Phys Med Rehabil Clin N Am 10(3): 729-754.

  • Van Zundert J, Patijn J, Kessels A et al. (January 2007) Pulsed radiofrequency adjacent to the cervical dorsal root ganglion in chronic cervical radicular pain: A double blind sham controlled randomized clinical trial. Pain 127(1-2): 173-182.

  • Varani K, Gessi S, Merighi S, Iannotta V, Cattabriga E, Spisani S, et al. Effect of low frequency electromagnetic fields on A2A adenosine receptors in human neutrophils. British Journal of Pharmacology. 2002; 136(1):57-66.

  • Weadock, K., Olson, R. M. and Silver, F. H. Evaluation of Collagen Crosslinking Rechniques. Biomater. Med. Devices Artif. Organs. 11, 293-318 (1984).

  • Weintraub M I, Cole S P. (July-August 2008) A randomized controlled trial of the effects of a combination of static and dynamic magnetic fields on carpal tunnel syndrome. Pain Med 9(5): 493-504.

  • Weintraub M I, Herrmann D N, Smith A G et al. (July 2009) Pulsed electromagnetic fields to reduce diabetic neuropathic pain and stimulate neuronal repair: A randomized controlled trial. Arch Phys Med Rehabil 90(7): 1102-1109.

  • Wolcott, L. E., Wheeler, P. C., Hardwicke, H. M. and Rowley, B. A. Accelerated Healing of Skin by Electrotherapy: Preliminary Clinical Results. Southern Med. 62, 795-801 (1969).

  • Wong J Y, Rapson L M. (August 1999) Acupuncture in the management of pain of musculoskeletal and neurologic origin. Phys Med Rehabil Clin N Am 10(3): 531-545, vii-viii.

  • Wróbel M P, Szymborska-Kajanek A, Wystrychowski G et al. (September 2008) Impact of low frequency pulsed magnetic fields on pain intensity, quality of life and sleep disturbances in patients with painful diabetic polyneuropathy. Diabetes Metab 34(4 Pt 1): 349-354.

  • Wu, K. T., Go, N., Dennis, C., Enquist, I. F. and Sawyer, P. N. Effects of Electric Currents and Interfacial Potentials on Wound Healing. J. Surg. Res. 7, 122-128 (1967).

  • Yannas, I. V. and Burke, J. F. Design of an Artificial Skin. I. Basic design principles. J. Biomed. Mater. Res. 14, 65-81, (1980).

  • Yoo M, Cho Y, Kim K, Chun Y, Chung C. Pulsed Electromagnetic Fields Treatment For The Early Stages Of Osteonecrosis Of The Femoral Head. Journal of Bone & Joint Surgery, British Volume. 2004 Feb. 1, 2004; 86-B(Supp. II):148-9.

  • Zimmerman, M., Parsons, J. R., Alexander, H. and Weiss, A. B. The Electrical Stimulation of Bone Using a Filamentons Carbon Cathode. J. Biomed. Mat. Res. 18, 927-938 (1984).

  • Zorzi C, Dall'Oca C, Cadossi R et al. (July 2007) Effects of pulsed electromagnetic fields on patients' recovery after arthroscopic surgery: Prospective, randomized and double-blind study. Knee Surg Sports Traumatol Arthrosc 15(7): 830-834

  • See, U.S. Pat. Nos. 2,400,316; 2,497,164; 2,648,727; 3,043,310; 3,181,535; 3,270,746; 3,329,148; 3,329,149; 3,658,051; 3,797,500; 3,800,802; 3,820,888; 3,890,953; 3,893,462; 3,902,502; 3,915,151; 3,952,751; 3,978,864; 4,028,518; 4,095,588; 4,105,017; 4,128,824; 4,177,796; 4,197,851; 4,233,965; 4,266,532; 4,305,115; 4,315,503; 4,338,945; 4,340,063; 4,374,482; 4,428,366; 4,454,882; 4,461,300; 4,479,388; 4,548,208; 4,550,714; 4,556,051; 4,586,509; 4,616,629; 4,627,438; 4,641,633; 4,654,574; 4,672,951; 4,674,482; 4,765,310; 4,793,325; 4,829,984; 4,850,372; 4,889,526; 4,911,686; 4,926,881; 4,937,323; 4,940,453; 4,942,880; 4,993,413; 4,998,532; 5,000,000; 5,000,178; 5,001,000; 5,008,561; 5,014,699; 5,058,582; 5,116,304; 5,123,898; 5,147,284; 5,181,902; 5,195,941; 5,224,922; 5,269,747; 5,273,033; 5,314,401; 5,338,286; 5,351,389; 5,370,680; 5,386,837; 5,401,233; 5,407,421; 5,441,495; 5,441,527; 5,478,303; 5,480,373; 5,514,175; 5,518,496; 5,529,569; 5,565,005; 5,584,863; 5,595,564; 5,703,735; 5,707,334; 5,718,246; 5,718,721; 5,723,001; 5,743,844; 5,766,231; 5,778,894; 5,792,209; 5,814,078; 5,877,627; 5,908,444; 5,951,459; 5,960,500; 5,960,513; 5,968,527; 5,983,134; 5,990,177; 5,997,464; 6,004,257; 6,011,994; 6,024,691; 6,029,084; 6,048,302; 6,075,603; 6,083,149; 6,086,525; 6,087,652; 6,099,459; 6,132,361; 6,132,362; 6,149,577; 6,155,966; 6,169,963; 6,174,276; 6,179,772; 6,186,941; 6,190,893; 6,200,259; 6,213,934; 6,217,604; 6,231,187; 6,231,528; 6,234,953; 6,246,912; 6,261,221; 6,261,831; 6,285,514; 6,301,506; 6,321,119; 6,321,120; 6,334,069; 6,348,070; 6,371,905; 6,418,345; 6,421,562; 6,424,863; 6,425,852; 6,434,426; 6,443,883; 6,450,941; 6,458,151; 6,458,157; 6,463,336; 6,535,767; 6,556,872; 6,560,489; 6,561,968; 6,564,093; 6,569,654; 6,589,159; 6,629,971; 6,647,301; 6,648,812; 6,652,473; 6,675,047; 6,678,562; 6,684,108; 6,701,185; 6,819,210; 6,839,589; 6,839,595; 6,844,378; 6,853,864; 6,856,839; 6,895,282; 6,919,205; 6,934,580; 6,955,642; 6,995,013; 7,010,353; 7,022,506; 7,039,467; 7,089,060; 7,113,830; 7,117,034; 7,130,692; 7,158,835; 7,160,241; 7,162,303; 7,167,753; 7,175,587; 7,177,695; 7,177,696; 7,215,995; 7,228,178; 7,280,861; 7,288,062; 7,333,858; 7,354,393; 7,354,748; 7,361,136; 7,367,988; 7,374,916; 7,419,474; 7,429,471; 7,456,189; 7,465,546; 7,465,566; 7,468,264; 7,507,198; 7,513,906; 7,517,311; 7,520,849; 7,551,957; 7,563,224; 7,564,267; 7,566,295; 7,587,230; 7,602,218; 7,617,005; 7,620,451; 7,647,115; 7,653,438; 7,659,750; 7,662,615; 7,696,860; 7,717,948; 7,740,574; 7,7445,24; 7,744,869; 7,758,490; 7,768,338; 7,783,348; 7,797,552; 7,819,794; 7,829,535; 7,840,272; 7,842,432; 7,867,235; 7,896,797; 7,937,143; 7,939,218; 7,981,611; 7,988,613; 8,014,846; 8,017,369; 8,029,432; 8,039,031; 8,060,210; 8,065,015; 8,070,703; 8,079,966; 8,131,371; 8,131,372; 8,142,774; 8,145,316; 8,145,317; 8,150,518; 8,150,519; 8,150,520; 8,167,784; 8,175,711; 8,292,834; 8,313,908; 8,343,027; 8,346,367; 8,347,891; 8,376,925; 8,412,328; 8,412,346; 8,415,123; 8,430,805; 8,433,423; 8,435,166; 8,444,640; 8,454,543; 8,454,594; 8,460,167; 8,477,003; 8,478,422; 8,548,600; 8,551,069; 8,560,077; 8,569,050; 8,571,642; 8,600,514; 8,620,423; 8,626,300; 8,657,732; 8,682,448; 8,684,998; 8,721,637; 8,728,137; 8,728,138; 8,740,896; 8,768,454; 8,768,470; 8,771,252; 8,774,913; 8,774,922; 8,775,340; 8,784,463; 8,785,196; 8,795,147; 8,805,521; 8,805,545; 8,818,514; 8,827,886; 8,845,629; 8,852,163; 8,880,186; 8,906,659; 8,911,342; 8,932,196; 8,934,978; 8,936,560; 8,936,804; 8,948,865; 8,958,871; 8,961,385; 8,968,172; 8,972,024; 8,979,727; 8,980,851; 8,983,595; 8,986,294; 8,998,791; 9,002,477; 9,005,102; 9,023,037; 9,072,527; 9,108,040; 9,119,829; 9,125,661; 9,131,978; 9,138,281; 9,186,198; 9,186,213; 9,186,514; 9,192,715; 9,198,792; 9,215,788; 9,232,986; 9,245,675; 9,265,558; 9,265,794; 9,278,231; 9,289,255; 9,289,618; 9,308,043; 9,308,044; 9,314,363; 9,314,630; 9,320,561; 9,320,913; 9,321,662; 9,326,817; 9,327,115; 9,327,119; 9,327,122; 9,327,136; 9,339,641; 9,345,909; 9,351,790; 9,352,002; 9,359,233; 9,364,267; 9,364,280; 9,387,338; 9,387,339; 9,393,144; 9,402,992; 9,415,233; 9,421,357; 9,421,370; 9,427,598; 9,404,449; 9,411,030; 9,415,233; 9,421,357; 9,421,370; 9,427,598; 9,433,629; 9,433,682; 9,433,797; 9,439,726; 9,440,089; 9,445,867; 9,452,297; 9,456,869; 9,463,066; 9,468,497; 9,474,563; 9,480,991; 9,486,270; 9,486,638; 9,498,491; 9,498,638; 9,498,639; 9,510,931; 9,526,918; 9,532,832; 9,554,935; 9,556,243; 9,603,637; 9,610,443; 9,610,459; 9,612,308; 9,630,001; 9,630,004; 9,636,174; 9,656,096; 9,662,183; 9,669,074; 9,675,413; 9,684,074; 9,694,193; 9,694,194; 9,707,035; 9,724,308; 9,724,534; 9,726,738; 9,727,764; 9,730,946; 9,731,132; 9,735,629; 9,743,983; 9,746,407; 9,757,192; 9,757,193; 9,757,583; 9,757,584; 9,758,806; 9,776,014; 9,795,500; 9,796,609; 9,801,905; D762864; D763453; D706432; RE41391; 20010007937; 20010027278; 20010031906; 20010031986; 20010041820; 20010044643; 20020022863; 20020034796; 20020035358; 20020052634; 20020086842; 20020091850; 20020147380; 20020165583; 20030018368; 20030023283; 20030028072; 20030050527; 20030083537; 20030093028; 20030095022; 20030099979; 20030125661; 20030125769; 20030130709; 20030158583; 20030158585; 20030163168; 20030171640; 20030176895; 20030181791; 20030195594; 20030211084; 20040005297; 20040006373; 20040054379; 20040073260; 20040073269; 20040077923; 20040106843; 20040122281; 20040138709; 20040138722; 20040176803; 20040176805; 20040176806; 20040210254; 20040230224; 20040241311; 20040267333; 20047744524; 20050005120; 20050049640; 20050059153; 20050065394; 20050084962; 20050124847; 20050134265; 20050148807; 20050154426; 20050165460; 20050177203; 20050182287; 20050187423; 20050197522; 20050198812; 20050215842; 20050222625; 20050228209; 20050251229; 20050259373; 20050267355; 20050288744; 20057740574; 20057758490; 20060009825; 20060024822; 20060030896; 20060030906; 20060051328; 20060057693; 20060085049; 20060094112; 20060094924; 20060129022; 20060161226; 20060190043; 20060205993; 20060206174; 20060212077; 20060235473; 20060240316; 20060245217; 20060258896; 20060271131; 20060293724; 20070014055; 20070021645; 20070026514; 20070027355; 20070030176; 20070038252; 20070039211; 20070043254; 20070060477; 20070060954; 20070060981; 20070065420; 20070078292; 20070104694; 20070105769; 20070139167; 20070149901; 20070173904; 20070203389; 20070203390; 20070208249; 20070208385; 20070212538; 20070282156; 20070288072; 20070299472; 20080015463; 20080021327; 20080039901; 20080058793; 20080077193; 20080092435; 20080097142; 20080125617; 20080132971; 20080140155; 20080200749; 20080208284; 20080208287; 20080215113; 20080215116; 20080217263; 20080228185; 20080269838; 20080280169; 20080280826; 20080287730; 20080288035; 20080294269; 20080306325; 20090018613; 20090030476; 20090043188; 20090062885; 20090099623; 20090104160; 20090105781; 20090131739; 20090132010; 20090156884; 20090163762; 20090206882; 20090206883; 20090206907; 20090216068; 20090227829; 20090227831; 20090234179; 20090234417; 20090240310; 20090287126; 20090326315; 20090326602; 20100004500; 20100005571; 20100010288; 20100049262; 20100057655; 20100075211; 20100082079; 20100121407; 20100160712; 20100160999; 20100168501; 20100179373; 20100185041; 20100197993; 20100204538; 20100210893; 20100221346; 20100222629; 20100222631; 20100239544; 20100262052; 20100298624; 20110004261; 20110021863; 20110065976; 20110065977; 20110105959; 20110112352; 20110112522; 20110118852; 20110124717; 20110130618; 20110152598; 20110160811; 20110184223; 20110190849; 20110207989; 20110213195; 20110217775; 20110224480; 20110282412; 20110288611; 20110295339; 20120016442; 20120038441; 20120059287; 20120078328; 20120089201; 20120101327; 20120101544; 20120116149; 20120135390; 20120135392; 20120143285; 20120149968; 20120172653; 20120184800; 20120215281; 20120245403; 20120253101; 20120265048; 20120302821; 20120316482; 20120330090; 20130013339; 20130035539; 20130072746; 20130085317; 20130158456; 20130158634; 20130165829; 20130171094; 20130178425; 20130218235; 20130238061; 20130238062; 20130245358; 20130261374; 20130267003; 20130267020; 20130274540; 20130288260; 20130289416; 20130293327; 20130296940; 20130317282; 20130344559; 20140023983; 20140024882; 20140046115; 20140046117; 20140046232; 20140046423; 20140066837; 20140081070; 20140114382; 20140148870; 20140155799; 20140163304; 20140207018; 20140207040; 20140207041; 20140213843; 20140213844; 20140221726; 20140228620; 20140249354; 20140249355; 20140303425; 20140322292; 20140342300; 20140342428; 20140343642; 20140350649; 20150005672; 20150010499; 20150025299; 20150094521; 20150099804; 20150107774; 20150141736; 20150151136; 20150174166; 20150196771; 20150202454; 20150217107; 20150217125; 20150217126; 20150258346; 20150273221; 20150297910; 20150306412; 20150315539; 20150320697; 20150328033; 20150328034; 20150328476; 20150342661; 20160000870; 20160008024; 20160015432; 20160015545; 20160022989; 20160038753; 20160051827; 20160067103; 20160067515; 20160067517; 20160074670; 20160074671; 20160121135; 20160129273; 20160129274; 20160129284; 20160145571; 20160151416; 20160151646; 20160193466; 20160206876; 20160228721; 20160228723; 20160235983; 20160246944; 20160306042; 20160313159; 20160317828; 20160331990; 20160339261; 20160346016; 20160346561; 20160354446; 20160372362; 20170000536; 20170001025; 20170001201; 20170027858; 20170028184; 20170030188; 20170039404; 20170043177; 20170050019; 20170056644; 20170071977; 20170072210; 20170080245; 20170087367; 20170113059; 20170113060; 20170128538; 20170151442; 20170152500; 20170157318; 20170165496; 20170173076; 20170173295; 20170173347; 20170202509; 20170209717; 20170225005; 20170226463; 20170246481; 20170252574; 20170266443; 20170266458; 20170266459; 20170291039; 20170295778; 20170298340; 20170298341; 20170304642; 20170319250; EP1216076; WO0115774; WO0209811; WO2004108208; WO2005051306; WO2008070001; WO2009155516; WO2010067336; WO2010149164; WO2011053607; WO8301742; WO9527533; WO9611723; WO9632158;



SUMMARY OF THE INVENTION

A system and method is provided for applying a low strength, low frequency magnetic field therapy to biological tissues.


A low frequency oscillating current is passed through a coil configured to induce a magnetic field strength of about 0.01-5 mTesla at a distance of 1 cm from the coil (or a cover over the coil), at a pulse frequency within the range 0.5-1,000 Hz, and more generally 5-1,000 Hz, for example at 100 Hz. The coil is e.g., 5-200 turns, having a diameter of 2-20 mm, of 0.2 mm copper wire, with a hollow core.


With each rising and falling edge of a pulse (e.g., square wave), the inductor coil establishes a magnetic field that oscillates with a frequency spectrum that is dependent on the risetime and falltime of the pulse. A pulse occurs with each transition (edge of the square wave), of alternating polarity. The circuit acts as a filter, and with a quality audio amplifier with sufficient headroom driving the circuit, the pulses will contain strong frequency components at 10-24 kHz. Thus, the signal emitted from the coil will typically be a low frequency square wave magnetic field at the pulse edge rate, i.e., double the 0.5-1,000 Hz pulse rate, and a high frequency emission that may be an underdamped oscillation, overdamped oscillation, or critically damped oscillation within the decay period that accompanies each edge transition, dependent on the amplifier and circuit components. Due to the power storage in the inductive coil and capacitor during excitation with the square wave, the peak power of the damped oscillation is not directly related to the power output capacity of the audio amplifier that drives the circuit, though the average power will generally be so limited.


Typically, the sharper the edge of the pulse, the greater the high frequency components in the electrical signal. With a quality audio amplifier driven by a digital to analog converter designed for digital audio sources, the frequency range may be flat (e.g., <3 dB rolloff) to >20 kHz, with a digital sampling rate of ˜44.1 kHz (or in some cases, 196 kHz). However, in such audio circuits, the digital source typically exceeds the bandwidth of the analog signal, and the typical audio range extends to about 20 kHz, so the amplifier may have a low pass filter (smoothing filter) which reduces “digital noise” above 20 kHz. The current is preferably controlled by a smartphone or other programmable device, and may be provided through an audio jack or other mechanical electronics connector. Alternately, a digital interface and/or wireless interface may control the current. An app on the smartphone may be used to control the frequency, amplitude/envelope modulation, waveform, duration, etc. of the oscillation. The coil may be in mineral or plastic housing with a simple filter, and TRRS-type audio jack.


A circuit may be provided which resonates, e.g., at a frequency below 100 kHz, and in particular which causes a ringing upon abrupt change in a voltage applied to the circuit. Thus, a pulse train (symmetric or asymmetric) may be received by the device comprising the circuit and the coil, which is excited by the pulses, and resonates with a decay upon each transition. Typically, the circuit is passive, but in some embodiments, it contains diodes, transistors, integrated circuits, or the like. For example, some audio amplifiers may seek to damp the ringing within the circuit, and therefore it may be advantageous to include active or passive edge sharpening electronics within the device, which can be achieved through use of semiconductors, e.g., a digital control or analog devices that have nonlinear transfer functions and those that act as “triggers”.


There is an emerging trend to eliminate an audio amplifier within a smartphone, which is replaced with a wireless interface (e.g., Bluetooth) or a wired interface. Therefore, while a passive device is currently preferred for use with smartphones or other programmable devices that have their own analog audio interface, the technology may also be used with active circuits that internally generate the excitation for the coil. However, while the device can autonomously generate the pulsed electromagnetic field (PEMF) therapy, it is preferred that the controlling device be connected to an on-line communications network for upload of feedback, user input, and sensor data, and download of therapy plans and excitation parameters. Therefore, one aspect of the technology is to provide a PEMF device that is part of the “Internet of Things”. However, because of the possibility of interference between the communications of the device and the therapy to be administered, in a preferred embodiment, communications are not concurrent with therapy. This, however, may be dependent on a number of factors, and is not a required attribute in all cases.


The smartphone may control the device to apply a therapy according to various theories. The device is not limited to any particular set of excitation parameters, and indeed a particular advantage is that a therapist can design different regimens using the same system. Likewise, while this is not required, the smartphone provides a convenient means for patient feedback, and may thus permit an adaptive therapy. In the case of acute pain relief, the smartphone may employ a genetic algorithm to explore various treatment parameters, seeking for a particular patient the optimum, which may vary over time. A remote server may receive feedback (which may be anonymized in some cases), allowing the various states of the genetic algorithm to be tested over a large population, which can therefore reveal patient subpopulations and groups, and expand the testing space to a degree larger than possible with a single patient.


It is preferred that, if the smartphone is in close proximity to the patient at the time of therapy, that the therapy be applied with the smartphone in “airplane mode”, that is, with radio frequency communications from the phone deactivated. This will avoid exposing the patient to potentially harmful high frequency waves during the therapy. Therefore, required remote communications are buffered for transmission after the therapy is concluded. Likewise, any required parameter downloads must be complete prior to initiation of therapy.


The coil is advantageously disposed within a spherical housing, which may have a bored cylindrical hole for the coil, and an electrical connector extending therefrom. Based on current technologies, a 3.5 mm phono jack or TRRS jack is available on many smartphones. However, some devices do not have this interface available. Therefore, another available interface may be used, such as a wired digital interface, such as USB (2, 3, 3.1, etc.), Thunderbolt, etc., and wireless interfaces, such as WiFi, Bluetooth, NFC, Zigbee, Zwave, etc.


The device does not need a smartphone or other standard intelligent/programmable consumer device, and for example, may be driven by an internal microcontroller, AM or FM radio receiver, analog or digital circuitry, etc. However, a smartphone is advantageous because it permits relatively easy programming, and remote communications as may be appropriate. Note that as technologies advance, the form factor and suite of functionality in a “smartphone” may evolve. Since the PEMF therapy is not dependent on the phone per se, any device that suitably generates excitation for the coil, and accepts and responds to control parameters for generating the PEMF, may be used. According to present availability and ubiquity of smartphones and tablets, e.g., Android, Apple, Windows (e.g., mobile), Linux, Chrome, Blackberry OS, etc., this type of platform is convenient, capable and preferred.


It is therefore an object to provide a magnetic field therapy device, comprising: a conductive coil fed with a current, to supply a therapy to a tissue, the therapy comprising a magnetic field strength below 50 mT, preferably below 25 mT, more preferably below 10 mT, and most preferably below 5 mT, and may have a strength as low as 0.01 mT max. Preferably, the field penetrates into the tissue at least 1 cm.


The coil may be, for example, a single layer of between 5 and 200 turns, e.g., 0.2 mm copper wire, having an external diameter of between about 2 mm and 20 mm.


The excitation received by the circuit which excites the coil, may be an oscillating electrical signal having a frequency range from about 5 Hz to about 100 kHz.


The circuit may present an impedance of at least 8 Ohms at 100 Hz to a driver circuit.


The signal which drives the circuit may have a slew rate of ˜10 kHz, e.g., 1 V/100 μS=105 V/sec, and the circuit may have a nominal load impedance of 33Ω for signals having that slew rate.


The coil (and optionally circuit) may be contained within a housing, such as a spherical magnetically impermeable material, such as a mineral (natural or synthetic), polymer, or non-magnetic metal. The housing is configured to contact the skin, and thus permit a therapy of the tissues underneath the skin.


A filter may be provided, optionally within the housing, having at least one pole within a range of 5 Hz to 50,000 Hz, configured to filter the oscillating electrical signal supplied to the conductive coil. The filter may resonate upon transient changes in voltage. The filter may have a pole at about 3 kHz.


The conductive coil may have a diameter of about 5-10 or 10-12 mm, and preferably about 6-8 mm. The conductive coil may have a diameter of less than about 15 or 12 mm. The size and shape of the coil are governed by the laws of physics with respect to the magnetic field shape and strength. Thus, a deeper field typically requires a larger coil, which will require a higher current. If the coil is to be driven from an audio earphone jack amplifier, the maximum power available will be <200 mW, and typically <100 mW, corresponding to 1 V max into >8 Ohms. For example, with a 33 Ohm load resistor in the circuit, and a 1 V peak driven signal, the available average power will be about 30 mW. The presented impedance may be at least 30 Ohms.


The oscillating electrical signal may have a frequency range comprising 50 Hz. That is, the signal may assume a 50 Hz frequency, or be a broadband signal encompassing 50 Hz.


The cover may have a spherical surface having a diameter of about 15-30 mm preferably 20-25 mm, and most preferably 20 mm.


The cover may be formed of a magnetically impermeable mineral, such as quartz.


The input may comprise an analog phono jack, such as a 3.5 mm TRRS phono jack.


The input may also comprise a digital audio connector.


The filter may comprise a circuit board having at least one resistor and at least one capacitor.


The input may comprise a radio frequency receiver, the magnetic field therapy device further comprising a self-contained battery power source to power the radio frequency receiver and the conductive coil.


The input may be adapted to receive a signal from a smartphone. The smartphone may be configured to generate the oscillating electrical signal based on a downloadable app which executes under a smartphone operating system. The smartphone may be configured to execute the downloadable app in airplane mode, substantially without emission of radio frequency signals in excess of 25 MHz.


It is also an object to provide a magnetic field therapy method, comprising: providing a conductive coil, an input configured to receive an oscillating electrical signal and to supply a current to the conductive coil, to thereby generate an oscillating magnetic field surrounding the conductive coil, and a cover, surrounding the conductive coil and the filter, adapted to contact human or animal skin and pass the oscillating magnetic field substantially without distortion or attenuation; generating the oscillating electrical signal in a first state with a smartphone under control of a smartphone app; and emitting the generated oscillating magnetic field surrounding the conductive coil into the human or animal skin adjacent to the cover, at a magnetic field strength of at least 0.01 mTesla at a distance of 1 cm from the cover. The method may further comprise receiving a user input to the smartphone; and generating the oscillating electrical signal in a second state with the smartphone under control of the smartphone app, the second state comprising a different distribution of frequencies of the oscillating electrical signal than the first state.


Under excitation by the oscillating electrical signal at a voltage of 1 V peak-to-peak, a magnetic field of between 0.01 mTesla and 5 mTesla may be obtained within a human or animal tissue under the human or animal skin contacting a surface of the cover at a depth of 1 cm from the surface of the cover, aligned with an axis of the conductive coil.


An electrical filter may be provided within the cover. The electrical filter may comprise a circuit board having at least one resistor and at least one capacitor. The filter may have a pole at about 3 kHz.


The conductive coil may have an inner diameter of about 8 mm. The presented impedance at the input may be at least 30 Ohms, e.g., having a 33Ω resistor in series with the coil. This value is dependent on typical smartphone audio amplifier designs, and a 33Ω load impedance at 10 kHz is typically acceptable for such amplifiers in common devices. Of course, with a particular device, the value of the load impedance (and thus the amount of power that is available for the PEMF) can vary.


The oscillating electrical signal may have a frequency range comprising 50 Hz.


The cover may comprise a spherical section having a diameter of about 2 cm. The cover may be formed of a magnetically impermeable mineral.


The method may further comprise generating, on a display of the smartphone, an indication of at least a direction in which the cover should be moved over the human or animal skin.


The magnetic field excited for a 100 Hz oscillating electrical signal at a voltage of 1 V peak-to-peak may be at least 0.05 mTesla at a depth of 1 cm in the human or animal tissue beneath the human or animal skin contacting the surface of the cover.


The input may comprise an analog phono jack or a digital audio connector.


The input may comprise a radio receiver, and the magnetic field therapy device may further comprise a self-contained battery power source to power the radio receiver and the current to the conductive coil.


The smartphone may execute the downloadable app in airplane mode, substantially without emission of radio frequency signals in excess of 25 MHz.


The oscillating electrical signal may be a square wave signal.


The circuit within the device may, for example, have a non-linear transfer function semiconductor device which conducts or triggers in a voltage dependent manner, and therefore generates high frequency signal components from a signal transition. For example, a diode “turns on” at 0.3-0.6 V in forward conduction (depending on junction composition). A pair of back-to-back diodes thus would be operative for “edge sharpening” for both rising and falling pulses. Similarly, a bipolar transistor/JFET/FET circuit may provide greater control over the conduction threshold and frequency characteristics. Other types of semiconductor devices may also be used in a passive circuit.


The circuit may also contain an active semiconductor device. For example, the power in the audio signal may be harvested with a rectifier circuit (preferably germanium or Schottky diodes or FETs, due to the low operating voltages) and stored on a capacitor, which is then used to run the active circuit. A voltage multiplier or step-up circuit may be employed as appropriate. A separate power source may also be provided, independent of the audio signal.


Note that the pulse signal is typically a square wave, but in practice, this need not have a symmetric duty cycle. Preferably, the spacing between upswing and downswing of the pulses is greater than the settling time of the coil and capacitor circuit, though in some cases, it may be shorter, allowing a relatively continuous excitation of the magnetic field therapy. All characteristics of the excitation signal may be controlled within the digital parameters of the control circuit and the analog characteristics of the amplifier and other circuit components, under control of the software in the smartphone or other control device.


It is also an object to provide a method of treating a human or animal, comprising: providing a smartphone having a magnetically actuated acoustic speaker; placing the speaker proximate to skin; generating an acoustic emission from the acoustic speaker and an accompanying magnetic emission, within a frequency range of 10 Hz-1000 Hz, controlled with a downloadable application for the smartphone; receiving user feedback into the smartphone downloadable application representing a subjective therapeutic effect; and modifying the acoustic emission based on the feedback.


It is a further object to provide a method of treating a human or animal, comprising: providing a smartphone having an electromagnetic vibration motor; placing the electromagnetic vibration motor proximate to skin; generating a vibration from the electromagnetic vibration motor and an accompanying magnetic emission, controlled with a downloadable application for the smartphone; receiving user feedback into the smartphone downloadable application representing a subjective therapeutic effect; and modifying the vibration based on the feedback.


It is another object to provide a pulsed electromagnetic field therapy device, comprising: an interface configured to receive an oscillating electrical signal from a programmable device; a coiled conductor, having at least 5 turns, and an inner diameter of between about 4-15 mm; a magnetically impermeable cover, having an outer surface configured for contact with human or animal skin; and a circuit within the magnetically impermeable cover, configured to excite the coiled conductor with a current corresponding to the oscillating electrical signal, to generate a magnetic field of between about 10 μTesla and 5 mTesla at a distance of 1 cm from the cover at a position axially aligned with the coiled conductor.


The interface may comprise an analog audio interface, presenting an impedance of between about 8-100 Ohms. The coiled conductor may comprise copper wire. The circuit may comprise a resistor and a capacitor.


The magnetically permeable cover may comprise a natural or synthetic mineral.


The pulsed electromagnetic field therapy device may further comprise a light emitting diode configured to illuminate in an emission pattern corresponding to an amplitude of the oscillating electric signal.


The interface may comprise a Bluetooth, WiFi, Zigbee, Zwave, or Near Field Communication protocol receiver.


The interface may comprise a 3.5 mm headphone jack analog audio interface, presenting an impedance of between about 8-100 Ohms.


The interface may comprise a microphone.


The circuit may comprise a capacitor in series with the coiled conductor.


It is another object to provide a pulsed electromagnetic field therapy method, comprising: receiving a pulse train from a programmable device, having a pulse frequency of between 5-1,000 Hz; passing a current corresponding to the pulse train through a coiled conductor having an inner diameter of between about 4-15 mm, within a cover configured to contact an exposed surface of a subject; emitting a pulse electromagnetic field from the coiled conductor corresponding to the current, having a maximum field strength of between about 10 μTesla and 5 mTesla at a distance of 1 cm from the cover at a position axially aligned with the coil coiled conductor, to thereby apply a pulsed electromagnetic field therapy to the subject.


The programmable device may comprise a mobile telecommunication device having an application program downloaded through a telecommunication port, the application program controlling an audio interface of the mobile telecommunication device to generate the pulse train, and controlling a user interface of the mobile telecommunication device to receive user input to at least initiate generation of the pulse train.


The method may further comprise receiving feedback from the subject relating to an effect of the pulsed electromagnetic field therapy.


The method may further comprise communicating a signal corresponding to the feedback from the mobile telecommunication device to a remote server through a communication network.


The method may further comprise receiving from the remote server a set of parameters for controlling generation of the pulse train. The set of parameters may comprise a pulse train frequency, and a pulse train duration.


The electromagnetic field therapy may comprise a resonant discharge of stored energy from the coiled conductor.


The passing a current corresponding to the pulse train through a coiled conductor may comprise passing the current through a capacitor and the coiled conductor.


The cover may have a spherical surface. The spherical surface may have a diameter of between 15 and 25 mm, e.g., about 20 mm.


The power for emission of the pulsed electromagnetic field therapy may be derived from the received pulse train or from a self-contained power source distinct from the pulse train.


The method may further comprise producing an optical signal when the pulsed electromagnetic therapy is in progress. The power for generating the optical signal may be derived from the received pulse train or a self-contained power source distinct from the pulse train. The pulse train may be received wirelessly. The pulse train may be received through a Bluetooth, WiFi, or NFC receiver, or an analog headphone jack, presenting a load of at least 30 Ohms, for example. The pulse train may also be received as an acoustic communication through a microphone.


The programmable device may generate an analog output having a plurality of different programmable sampling rates, further comprising selecting a sampling rate to alter the pulsed electromagnetic field therapy. The plurality of different programmable sampling rates comprise 44.1 kHz, 48 kHz, and 96 kHz. The pulse train may be a square wave pulse train. The pulse train may have a symmetric or asymmetric duty cycle.


It is a further object to provide a pulsed electromagnetic field therapy method, comprising: receiving a pulse signal from a programmable device, having a pulse repetition rate of between 5-1,000 pulses per second; passing a current corresponding to the pulse train through a coiled conductor having an inner diameter of between about 4-15 mm, within a cover configured to contact an exposed surface of a subject, the current having an asymmetric rise and fall; and emitting a pulse electromagnetic field from the coiled conductor corresponding to the current, having a maximum field strength of between about 10 μTesla and 5 mTesla at a distance of 1 cm from the cover at a position axially aligned with the coil coiled conductor, to thereby apply a pulsed electromagnetic field therapy to the subject.


It is another object to provide a magnetic field therapy device, comprising: a conductive coil having a diameter of between about 8 mm and 15 mm and having between 5-1000 turns; an analog input configured to receive an electrical signal from an analog audio interface device, a high pass filter; and a non-magnetic cover, surrounding the conductive coil and the filter, adapted separate the conductive coil from contact with an adjacent human or animal tissue substantially without disrupting a magnetic field emitted from the conductive coil, wherein under excitation by the electrical signal comprising square wave pulses at a frequency of 100 Hz and a voltage of 1 V peak-to-peak, a magnetic field of between 0.01 mTesla and 5 mTesla maximum is obtained at a distance of 1 cm from the cover.


The filter may comprise a resistor having a resistance of between about 10 Ohms and 100 Ohms, and a ceramic capacitor having a capacitance of about 1-50 μFarads, and the coiled conductor has between 5 and 200 turns.





BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 shows a schematic of an electrical circuit according to the present invention.



FIG. 2 shows a physical arrangement of a preferred embodiment of the invention.



FIG. 3 shows an assembled view of a preferred embodiment of the invention with a spherical case.



FIG. 4 shows an example of the device, plugged into a headphone jack of a smartphone, being used to apply a therapy to an upper arm region.





DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A preferred embodiment of the technology provides a small device that can be plugged into a standard headphone jack socket on any smartphone (Android or iPhone) and used with a downloaded software app.


A jackplug holder may also be provided so the device can be worn as a necklace when not in use. A keyring embodiment may also be provided.


The schematic is simple, consisting of 4 components, as shown in FIG. 1: A 16 turn (single layer) coil, 7.8-8 mm diameter, 0.2 mm enameled copper wire, on a P14 hollow core former (Farnell, 235-5082), in series with a 33 Ohm 0.1 W resistor in parallel with a 10 μF, >10 V ceramic capacitor (e.g., 1210 case, Farnell 249-7164). The resistor and capacitor are mounted to a 8-10 mm PCB (e.g., 0.6 mm FRP) soldered to the jackplug sleeve solder tag. The end of the coil and the resistor and capacitor are mounted on, and connected to, the tip and ring 2 contacts of a 3.5 mm TRRS headphone jack. The coil is inserted into a 20 mm glass or mineral ball, such as a quartz sphere with a bored 8-10 mm dimeter, 15-18 mm deep cylindrical, glued or epoxied to the end of the TSSR jack (Lumberg 1532 02 Phone Audio Connector, Plug, 3.5 mm, 4 Contacts, Cable Mount, Plastic Body, Nickel Plated Contacts, Farnell 2101773). The arrangement is shown in FIG. 2.


The resistor and capacitor can be housed inside the bobbin to reduce total length of device.


The excitation through the headphone jack may be e.g., a 100 Hz square wave.


According to one theory, all frequencies used can be considered as musical tone frequencies when the all tones are tuned to the keynote 453.3 Hz—which is an important proton resonance. When more than one frequency is concurrently used, a musical chord may be generated. It is noted that it is unlikely that tissues respond to musical theory. However, the PEMF can excite afferent nerves and be communicated to the brain, which can then respond centrally or through efferent pathways.


The frequencies may have a symphonic quality, and as such need not be simple square waves, and rather may be arbitrary waveforms with dynamically changing frequencies.


The fundamental frequencies, in fact, may extend to 10 kHz, and perhaps beyond.



FIG. 3 shows an assembled view of a preferred embodiment of the invention with a spherical case natural semi-transparent mineral case, showing the coil wound around a bobbin centrally located within the sphere, and a TRRS phono jack extending axially from the sphere. A mineral sphere (e.g., amethyst) was been found to be ergonomically and aesthetically acceptable, with respect to mass, thermal capacity (relevant to skin contact), magnetic characteristics, etc.


The device may be conveniently provided with a necklace-holder, which has a dummy TRRS socket to retain the device when not in use. The necklace provides a convenient way to carry and transport the device. A corresponding holder may be formed as a keyring, or the like.



FIG. 4 shows an example of the device, in use, plugged in to the headphone jack of a typical cellphone. The cellphone may be operated in “airplane mode”, and the app may enforce this as a restriction of use, in order to avoid potential interference between radio frequency emissions from the radio(s) within the phone and the PEMF. An exception may be the use of Bluetooth to communicate the signal to the device, though it is preferred to have no RF emissions from the phone during PEMF therapy. Because the PEMF is preferably generated based a square wave (a digital type signal), it may be possible to program a digital interface (e.g., USB) to generate the excitation signal for the device, rather than the audio output of the cellphone.


a downloadable smartphone app according to the present technology may be provided, having various interface screens. In the first screen, a splash screen may be provided. Typically, during PEMF therapy, it is desired to provide a relaxing environment, and the screens should be designed with muted colors, and avoidance of distractions. In the second screen, a set of different programs may be provided, which generate different output excitation signal patterns, such as “pain relief”, “muscle tension”, and “relaxation”. The interface may also provide a user history option and a setup option. The “pain relief” screen is exemplary, and may include relevant user-identification information (name, birthdate, gender), body location to be treated, an intensity control slider, a PEMF therapy duration input, and a “start” screen button. This screen input may be used to represent a pre-treatment (subjective) evaluation of the patient condition.


During therapy, soothing patterns which optionally correspond to the treatment protocol may be shown on the screen, and may be animated accordingly.


A personalized user screen may show a summary of a treatment session, and provide a control button to stop the therapy. The app may also sense when the device is removed from the headphone jack, and preferably immediately cease generation of the excitation signal to avoid driving the internal phone speaker with the square wave pulses. The screen may provide an input for the patient to provide a post-treatment (subjective) evaluation, which can be used to track the therapy.


The app can also receive input from the user, post treatment, to provide subjective response factors. In some cases, objective data may be available. For example, where a vascular response to the therapy occurs, skin color, temperature, edema measurements, etc., may be acquired either automatically or manually, and input into the system. These inputs, either on an individual basis or on a population basis, may be used to tailor the therapy for the individual, for example by changing pulse frequency and/or duty cycle, pulse amplitude, therapy duration, or various patterns of excitation pulses. In some cases, the therapy may be responsive to the environment, for example, ambient temperature or illumination, and the smartphone can detect these parameters.


It is believed that various forms of musical phrasing, in particular styles of classical music, are particularly appropriate for PEMF. Therefore, the excitation parameters may model classic works, such as patterns and amplitudes of excitation pulses, combinations of excitation parameters (similar to musical chords), etc. As discussed above, it is unclear that the peripheral tissues are capable of particularly responding to these signals, but rather that communications from the periphery to the central nervous system are involved.

Claims
  • 1. A magnetic therapy device, comprising: an interface configured to receive an audio spectrum electrical signal comprising energy at a frequency of 1,000 Hz, from an audio signal port;a coil having an internal diameter of between 4 mm and 15 mm and having at least 5 turns, configured to emit a magnetic field in response to the audio spectrum electrical signal;an impedance load device having at least one pole within a range of 5 Hz to 50,000 Hz configured to present a predetermined minimum impedance of at least 8Ω at 100 Hz to the audio signal port; anda shell, surrounding the coil, configured to permit the magnetic field to pass therethrough undistorted.
  • 2. The magnetic therapy device according to claim 1, wherein the magnetic field has a field strength of between 0.01 mTesla and 5 mTesla at a distance of 1 cm from the shell in response to an oscillating electrical signal at a voltage of 1 V peak-to-peak at 100 Hz.
  • 3. The magnetic therapy device according to claim 1, wherein the impedance load device presents an impedance of at least 33 Ohms in response to an audio spectrum electrical signal having a slew rate of 105 V/sec, to the audio signal port.
  • 4. The magnetic therapy device according to claim 1, wherein the impedance load device presents an impedance of between 8 and 100 Ohms to the audio signal port and the coil has a maximum field strength between 0.1 and 15 mT at a distance of 1 cm from the shell in response to the audio spectrum electrical signal.
  • 5. The magnetic therapy device according to claim 1, wherein the shell comprises a spherical surface having a diameter of at least 2 cm.
  • 6. The magnetic therapy device according to claim 1, wherein the impedance load device comprises a circuit board having at least one resistor and at least one capacitor.
  • 7. The magnetic therapy device according to claim 1, wherein the impedance load device has a transfer function having a pole at about 3 kHz.
  • 8. The magnetic therapy device according to claim 1, wherein the interface comprises a phono jack.
  • 9. The magnetic therapy device according to claim 1, wherein the interface comprises a Bluetooth receiver.
  • 10. The magnetic therapy device according to claim 1, in combination with a smartphone under control of a smartphone app, wherein the audio spectrum electrical signal is received from the smartphone.
  • 11. The magnetic therapy device according to claim 10, wherein the smartphone app is configured to receive a user input to the smartphone, to produce oscillating magnetic fields corresponding to the audio spectrum electrical signal having at least two different states, under control of the smartphone app, comprising a first state with a different distribution of frequencies than a second state.
  • 12. A magnetic therapy method, comprising: receiving an audio spectrum electrical signal comprising energy at a frequency of 1,000 Hz from an audio signal port, into an impedance load device having at least one pole within a range of 5 Hz to 50,000 Hz which presents a predetermined minimum impedance of at least 8Ω at 100 Hz to the audio signal port;emitting a magnetic field in response to the audio spectrum electrical signal from a coil having an internal diameter of between 4 mm and 15 mm and having at least 5 turns surrounded with a shell, configured to permit the magnetic field to pass therethrough undistorted, having a maximum field strength between 0.1 and 15 mT at a distance of 1 cm from the shell in response to the audio spectrum electrical signal; anddefining the audio spectrum electrical signal with a smartphone app on a smartphone.
  • 13. The magnetic therapy method according to claim 12, wherein the smartphone app receives a user input to the smartphone, and the coil produces oscillating magnetic fields corresponding to the audio spectrum electrical signal having at least two different states, under control of the smartphone app, comprising a first state with a different distribution of frequencies than a second state.
  • 14. The magnetic therapy method according to claim 12, wherein the magnetic field is emitted with a maximum field strength of between 0.01 mTesla and 5 mTesla at a distance of 1 cm from the shell in response to an oscillating electrical signal at a voltage of 1 V peak-to-peak at 100 Hz.
  • 15. The magnetic therapy method according to claim 12, wherein the impedance load device presents an impedance of between 8 and 100 Ohms to the audio signal port.
  • 16. The magnetic therapy method according to claim 12, wherein the shell comprises a spherical surface having a diameter of at least 2 cm.
  • 17. The magnetic therapy method according to claim 12, wherein the audio signal port comprises a Bluetooth receiver.
  • 18. The magnetic therapy method according to claim 12, further comprising: receiving a user input to the smartphone to control the smartphone app;generating the audio spectrum magnetic field based on an audio output of the smartphone comprising a first distribution of frequencies; andgenerating the audio spectrum magnetic field based on an audio output of the smartphone comprising a second distribution of frequencies different from the first distribution of frequencies.
  • 19. The magnetic therapy method according to claim 12, further moving the shell with respect to skin during emission of the audio spectrum magnetic field.
  • 20. A electromagnetic field therapy device, comprising: a coil having an internal diameter of between 4 mm and 15 mm and having at least 5 turns, configured to emit an oscillating magnetic field corresponding to an audio spectrum signal comprising energy at a frequency of 1,000 Hz from a smartphone, under control of a smartphone app;a shell, having an outer surface configured for contact with human or animal skin, which does not perturb the oscillating magnetic field; anda circuit having at least one pole within a range of 5 Hz to 50,000 Hz within the cover, configured to electrically filter the audio spectrum signal and present an impedance to a signal source of at least 8 Ohms at 100 Hz,the electromagnetic field therapy device being configured to generate the oscillating magnetic field having a magnetic field strength between about 10 μTesla and 5 mTesla at a distance of 1 cm from the shell.
CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation of U.S. patent application Ser. No. 17/074,557, filed Oct. 19, 2020, now U.S. Pat. No. 11,344,741, issued May 31, 2022, which is a Continuation of U.S. patent application Ser. No. 15/809,684, filed Nov. 10, 2017, now U.S. Pat. No. 10,806,942, issued Oct. 20, 2020, which claims benefit of priority from, and is a non-provisional of, U.S. Provisional Patent Application No. 62/420,337, filed Nov. 10, 2016, the entirety of which are expressly incorporated herein by reference.

US Referenced Citations (812)
Number Name Date Kind
2648727 Rockwell et al. Aug 1953 A
3043310 Milinowski et al. Jul 1962 A
3181535 Milinowski et al. May 1965 A
3270746 Denis et al. Sep 1966 A
3329148 Denis et al. Jul 1967 A
3329149 Denis et al. Jul 1967 A
3658051 Maclean et al. Apr 1972 A
3797500 Porter Mar 1974 A
3800802 Berry et al. Apr 1974 A
3820888 Jordon et al. Jun 1974 A
3890953 Kraus et al. Jun 1975 A
3893462 Manning Jul 1975 A
3902502 Liss et al. Sep 1975 A
3915151 Kraus Oct 1975 A
3952751 Yarger Apr 1976 A
3978864 Smith Sep 1976 A
4028518 Boudouris et al. Jun 1977 A
4095588 Goldman et al. Jun 1978 A
4105017 Ryaby et al. Aug 1978 A
4128824 Mirsch Dec 1978 A
4177796 Franco-Vila Dec 1979 A
4197851 Fellus Apr 1980 A
4233965 Fairbanks Nov 1980 A
4266532 Ryaby et al. May 1981 A
4305115 Armitage Dec 1981 A
4315503 Ryaby et al. Feb 1982 A
4338945 Kosugi et al. Jul 1982 A
4340063 Maurer Jul 1982 A
4374482 Moore et al. Feb 1983 A
4428366 Findl et al. Jan 1984 A
4454882 Takano Jun 1984 A
4461300 Christensen Jul 1984 A
4479388 Matzuk Oct 1984 A
4548208 Niemi Oct 1985 A
4550714 Talish et al. Nov 1985 A
4556051 Maurer Dec 1985 A
4586509 Liss et al. May 1986 A
4616629 Moore Oct 1986 A
4627438 Liss et al. Dec 1986 A
4641633 Delgado Feb 1987 A
4654574 Thaler Mar 1987 A
4672951 Welch Jun 1987 A
4674482 Waltonen et al. Jun 1987 A
4765310 Deagle et al. Aug 1988 A
4793325 Cadossi et al. Dec 1988 A
4829984 Gordon May 1989 A
4850372 Ko et al. Jul 1989 A
4889526 Rauscher et al. Dec 1989 A
4911686 Thaler Mar 1990 A
4926881 Ichinomiya et al. May 1990 A
4937323 Silver et al. Jun 1990 A
4940453 Cadwell Jul 1990 A
4942880 Slovak Jul 1990 A
4993413 McLeod et al. Feb 1991 A
4998532 Griffith Mar 1991 A
5000000 Ingram et al. Mar 1991 A
5000178 Griffith Mar 1991 A
5001000 Rohrbacher et al. Mar 1991 A
5008561 Madeley et al. Apr 1991 A
5014699 Pollack et al. May 1991 A
5058582 Thaler Oct 1991 A
5116304 Cadwell May 1992 A
5123898 Liboff et al. Jun 1992 A
5147284 Fedorov et al. Sep 1992 A
5181902 Erickson et al. Jan 1993 A
5195941 Erickson et al. Mar 1993 A
5224922 Kurtz Jul 1993 A
5269747 Erickson et al. Dec 1993 A
5273033 Hoffman Dec 1993 A
5314401 Tepper May 1994 A
5338286 Abbott et al. Aug 1994 A
5351389 Erickson et al. Oct 1994 A
5370680 Proctor Dec 1994 A
5386837 Sterzer Feb 1995 A
5401233 Erickson et al. Mar 1995 A
5407421 Goldsmith Apr 1995 A
5441495 Liboff et al. Aug 1995 A
5441527 Erickson et al. Aug 1995 A
5478303 Foley-Nolan et al. Dec 1995 A
5480373 Fischer et al. Jan 1996 A
5514175 Kim et al. May 1996 A
5518496 McLeod et al. May 1996 A
5529569 Woo Jun 1996 A
5565005 Erickson et al. Oct 1996 A
5584863 Rauch et al. Dec 1996 A
5595564 Pinna Jan 1997 A
5703735 Bleeke Dec 1997 A
5707334 Young Jan 1998 A
5718246 Vona Feb 1998 A
5718721 Ross Feb 1998 A
5723001 Pilla et al. Mar 1998 A
5743844 Tepper et al. Apr 1998 A
5766231 Erickson et al. Jun 1998 A
5778894 Dorogi et al. Jul 1998 A
5792209 Varner Aug 1998 A
5814078 Zhou et al. Sep 1998 A
5877627 Fischer et al. Mar 1999 A
5908444 Azure Jun 1999 A
5951459 Blackwell Sep 1999 A
5960500 Bolton Oct 1999 A
5960513 Beshah Oct 1999 A
5968527 Litovitz Oct 1999 A
5983134 Ostrow Nov 1999 A
5990177 Brown Nov 1999 A
5997464 Blackwell Dec 1999 A
6004257 Jacobson Dec 1999 A
6011994 Kronberg Jan 2000 A
6024691 Tepper et al. Feb 2000 A
6029084 Long et al. Feb 2000 A
6048302 Markoll Apr 2000 A
6075603 O'Meara et al. Jun 2000 A
6083149 Wascher et al. Jul 2000 A
6086525 Davey et al. Jul 2000 A
6087652 O'Meara et al. Jul 2000 A
6099459 Jacobson Aug 2000 A
6132361 Epstein et al. Oct 2000 A
6132362 Tepper et al. Oct 2000 A
6149577 Bouldin et al. Nov 2000 A
6155966 Parker Dec 2000 A
6169963 Markov Jan 2001 B1
6174276 Blackwell Jan 2001 B1
6179772 Blackwell Jan 2001 B1
6186941 Blackwell Feb 2001 B1
6190893 Shastri et al. Feb 2001 B1
6200259 March Mar 2001 B1
6213934 Bianco et al. Apr 2001 B1
6217604 Azure et al. Apr 2001 B1
6231187 Munoz et al. May 2001 B1
6231528 Kaufman et al. May 2001 B1
6234953 Thomas et al. May 2001 B1
6246912 Sluijter et al. Jun 2001 B1
6261221 Tepper et al. Jul 2001 B1
6261831 Agee Jul 2001 B1
6285514 O'Meara et al. Sep 2001 B1
6301506 den Boer et al. Oct 2001 B1
6321119 Kronberg Nov 2001 B1
6321120 Surbeck et al. Nov 2001 B1
6334069 George et al. Dec 2001 B1
6348070 Teissl et al. Feb 2002 B1
6371905 March Apr 2002 B1
6418345 Tepper et al. Jul 2002 B1
6421562 Ross Jul 2002 B1
6424863 Flock et al. Jul 2002 B1
6425852 Epstein et al. Jul 2002 B1
6434426 Munneke et al. Aug 2002 B1
6443883 Ostrow et al. Sep 2002 B1
6450941 Larsen Sep 2002 B1
6458151 Saltiel Oct 2002 B1
6458157 Suaning Oct 2002 B1
6463336 Mawhinney Oct 2002 B1
6535767 Kronberg Mar 2003 B1
6556872 Hauck Apr 2003 B2
6560489 Hauck May 2003 B2
6561968 Dissing et al. May 2003 B1
6564093 Ostrow et al. May 2003 B1
6569654 Shastri et al. May 2003 B2
6589159 Paturu Jul 2003 B2
6629971 McDaniel Oct 2003 B2
6647301 Sederlund et al. Nov 2003 B1
6648812 Ardizzone Nov 2003 B2
6652473 Kaufman et al. Nov 2003 B2
6675047 Konoplev et al. Jan 2004 B1
6678562 Tepper et al. Jan 2004 B1
6684108 Surbeck et al. Jan 2004 B2
6701185 Burnett et al. Mar 2004 B2
6819210 Boynton et al. Nov 2004 B2
6839589 Petlan Jan 2005 B2
6839595 Tepper et al. Jan 2005 B2
6844378 Martin et al. Jan 2005 B1
6853864 Litovitz Feb 2005 B2
6856839 Litovitz Feb 2005 B2
6895282 Gellman et al. May 2005 B2
6919205 Brighton Jul 2005 B2
6934580 Osorio et al. Aug 2005 B1
6955642 Simon Oct 2005 B1
6995013 Connelly et al. Feb 2006 B2
7010353 Gan et al. Mar 2006 B2
7022506 Brighton et al. Apr 2006 B2
7039467 Hauck May 2006 B2
7089060 Fitzsimmons Aug 2006 B1
7113830 Hauck Sep 2006 B2
7117034 Kronberg Oct 2006 B2
7130692 Brighton et al. Oct 2006 B2
7158835 Brighton et al. Jan 2007 B2
7160241 Herbst Jan 2007 B1
7162303 Levin et al. Jan 2007 B2
7167753 Brighton et al. Jan 2007 B2
7175587 Gordon et al. Feb 2007 B2
7177695 Moran Feb 2007 B2
7177696 Pandelisev Feb 2007 B1
7215995 Brighton et al. May 2007 B2
7228178 Carroll et al. Jun 2007 B2
7280861 Thomas et al. Oct 2007 B2
7288062 Spiegel Oct 2007 B2
7333858 Killian et al. Feb 2008 B2
7354393 Ardizzone et al. Apr 2008 B2
7354748 Brighton Apr 2008 B2
7361136 Parker Apr 2008 B2
7367988 Litovitz May 2008 B1
7374916 Brighton May 2008 B2
7419474 Lee Sep 2008 B2
7429471 Brighton Sep 2008 B2
7456189 Himmelsbach et al. Nov 2008 B2
7465546 Brighton Dec 2008 B2
7465566 Brighton et al. Dec 2008 B2
7468264 Brighton et al. Dec 2008 B2
7507198 Ardizzone et al. Mar 2009 B2
7513906 Passy et al. Apr 2009 B2
7517311 Herbst Apr 2009 B1
7520849 Simon Apr 2009 B1
7551957 Whelan et al. Jun 2009 B2
7563224 Puchek Jul 2009 B2
7564267 Patterson Jul 2009 B1
7566295 Giardino et al. Jul 2009 B2
7587230 Litovitz Sep 2009 B2
7602218 Patterson Oct 2009 B2
7617005 Demarais et al. Nov 2009 B2
7620451 Demarais et al. Nov 2009 B2
7647115 Levin et al. Jan 2010 B2
7653438 Deem et al. Jan 2010 B2
7659750 Patterson Feb 2010 B2
7662615 Chang et al. Feb 2010 B2
7696860 Gilson et al. Apr 2010 B2
7717948 Demarais et al. May 2010 B2
RE41391 Brighton Jun 2010 E
7740574 Pilla et al. Jun 2010 B2
7744524 Pilla Jun 2010 B2
7744869 Simon Jun 2010 B2
7758490 Pilla et al. Jul 2010 B2
7768338 Patterson Aug 2010 B2
7783348 Gill et al. Aug 2010 B2
7797552 Kahn et al. Sep 2010 B2
7819794 Becker Oct 2010 B2
7829535 O'Connor Nov 2010 B2
7840272 Kronberg et al. Nov 2010 B2
7842432 Niu et al. Nov 2010 B2
7867235 Fell et al. Jan 2011 B2
7896797 Pilla et al. Mar 2011 B2
7937143 Demarais et al. May 2011 B2
7939218 Niu May 2011 B2
7981611 Brighton Jul 2011 B2
7988613 Becker Aug 2011 B2
8014846 Litovitz Sep 2011 B2
8017369 Brighton Sep 2011 B2
8029432 Dennis et al. Oct 2011 B2
8039031 Baianu et al. Oct 2011 B2
8060210 Carroll Nov 2011 B1
8065015 Brighton et al. Nov 2011 B2
8070703 Skahan et al. Dec 2011 B2
8079966 El-Bialy et al. Dec 2011 B2
8131371 Demarals et al. Mar 2012 B2
8131372 Levin et al. Mar 2012 B2
8142774 Simon Mar 2012 B2
8145316 Deem et al. Mar 2012 B2
8145317 Demarais et al. Mar 2012 B2
8150518 Levin et al. Apr 2012 B2
8150519 Demarais et al. Apr 2012 B2
8150520 Demarais et al. Apr 2012 B2
8167784 Honeycutt et al. May 2012 B1
8175711 Demarais et al. May 2012 B2
8292834 El-Bialy et al. Oct 2012 B2
8313908 Brighton Nov 2012 B2
8343027 DiMino et al. Jan 2013 B1
8346367 Carroll Jan 2013 B2
8347891 Demarais et al. Jan 2013 B2
8376925 Dennis et al. Feb 2013 B1
8412328 Whelan et al. Apr 2013 B2
8412346 Gellman et al. Apr 2013 B2
8415123 Pilla et al. Apr 2013 B2
8430805 Burnett et al. Apr 2013 B2
8433423 Demarais Apr 2013 B2
8435166 Burnett et al. May 2013 B2
8444640 Demarais et al. May 2013 B2
8454543 Skahan et al. Jun 2013 B2
8454594 Demarais et al. Jun 2013 B2
8460167 Chornenky et al. Jun 2013 B2
8477003 Wilson et al. Jul 2013 B2
8478422 Epstein et al. Jul 2013 B2
8548600 Deem et al. Oct 2013 B2
8551069 Demarais et al. Oct 2013 B2
8560077 Feinstein Oct 2013 B2
8569050 Ericsson Oct 2013 B1
8571642 Gill et al. Oct 2013 B2
8600514 Carroll Dec 2013 B1
8620423 Demarais et al. Dec 2013 B2
8626300 Demarais et al. Jan 2014 B2
8657732 Vasishta Feb 2014 B2
8682448 Weinstock Mar 2014 B2
8684998 Demarais et al. Apr 2014 B2
8721637 Zarins et al. May 2014 B2
8728137 Zarins et al. May 2014 B2
8728138 Zarins et al. May 2014 B2
D706432 Martinez Jun 2014 S
8740896 Zarins et al. Jun 2014 B2
8768454 Sham et al. Jul 2014 B2
8768470 Deem et al. Jul 2014 B2
8771252 Gelfand et al. Jul 2014 B2
8774913 Demarais et al. Jul 2014 B2
8774922 Zarins et al. Jul 2014 B2
8775340 Waxman et al. Jul 2014 B2
8784463 Zarins et al. Jul 2014 B2
8785196 Kronberg et al. Jul 2014 B2
8795147 Goodwin et al. Aug 2014 B1
8805521 Carroll Aug 2014 B2
8805545 Zarins Aug 2014 B2
8818514 Zarins et al. Aug 2014 B2
8827886 Chornenky et al. Sep 2014 B2
8845629 Demarais et al. Sep 2014 B2
8852163 Deem et al. Oct 2014 B2
8880186 Levin et al. Nov 2014 B2
8906659 Clyne et al. Dec 2014 B2
8911342 Dissing et al. Dec 2014 B2
8932196 Chornenky et al. Jan 2015 B2
8934978 Deem et al. Jan 2015 B2
8936560 Lunau et al. Jan 2015 B2
8936804 Lin et al. Jan 2015 B2
8948865 Zarins et al. Feb 2015 B2
8958871 Demarais et al. Feb 2015 B2
8961385 Pilla et al. Feb 2015 B2
8968172 Wang et al. Mar 2015 B2
8972024 Walker Mar 2015 B2
8979727 Ron Edoute et al. Mar 2015 B2
8980851 O'Connor Mar 2015 B2
8983595 Levin et al. Mar 2015 B2
8986294 Demarais et al. Mar 2015 B2
8998791 Ron Edoute et al. Apr 2015 B2
9002477 Burnett Apr 2015 B2
9005102 Burnett et al. Apr 2015 B2
9023037 Zarins et al. May 2015 B2
9072527 Deem et al. Jul 2015 B2
9108040 Zarins Aug 2015 B2
9119829 Higgins et al. Sep 2015 B2
9125661 Deem et al. Sep 2015 B2
9131978 Zarins et al. Sep 2015 B2
9138281 Zarins et al. Sep 2015 B2
9186198 Demarais et al. Nov 2015 B2
9186213 Deem et al. Nov 2015 B2
9186514 Ben-Haim et al. Nov 2015 B2
9192715 Gelfand et al. Nov 2015 B2
9198792 Skahan et al. Dec 2015 B2
9215788 Karni et al. Dec 2015 B2
9232986 Scurtescu Jan 2016 B2
9245675 Tsai et al. Jan 2016 B2
9265558 Zarins et al. Feb 2016 B2
9265794 Lin et al. Feb 2016 B2
9278231 Vasishta Mar 2016 B2
9289255 Deem et al. Mar 2016 B2
9289618 Ben-Haim et al. Mar 2016 B1
9308043 Zarins et al. Apr 2016 B2
9308044 Zarins et al. Apr 2016 B2
9314363 Ingimundarson et al. Apr 2016 B2
9314630 Levin et al. Apr 2016 B2
9320561 Zarins et al. Apr 2016 B2
9320913 Dimino et al. Apr 2016 B2
9321662 Holland Apr 2016 B2
9326817 Zarins et al. May 2016 B2
9327115 Neuman et al. May 2016 B2
9327119 Skahan et al. May 2016 B2
9327122 Zarins et al. May 2016 B2
9327136 Hedgecock May 2016 B2
9339641 Rajguru et al. May 2016 B2
9345909 Feferberg May 2016 B2
9351790 Zemel et al. May 2016 B2
9352002 Higgins et al. May 2016 B2
9359233 Holland Jun 2016 B2
9364267 Northcutt et al. Jun 2016 B2
9364280 Zarins et al. Jun 2016 B2
9387338 Burnett Jul 2016 B2
9387339 Sham et al. Jul 2016 B2
9393144 Ingimundarson et al. Jul 2016 B2
D762864 Anderson et al. Aug 2016 S
D763453 Anderson et al. Aug 2016 S
9402992 Zarins Aug 2016 B2
9404449 Licitar Aug 2016 B2
9411030 Weinberg Aug 2016 B2
9415233 Pilla et al. Aug 2016 B2
9421357 Walker Aug 2016 B2
9421370 Weinstock Aug 2016 B2
9427598 Pilla et al. Aug 2016 B2
9433629 Paz Garcia et al. Sep 2016 B2
9433682 Mohapatra et al. Sep 2016 B2
9433797 Pilla et al. Sep 2016 B2
9439726 Zarins et al. Sep 2016 B2
9440089 Pilla et al. Sep 2016 B2
9445867 Zarins et al. Sep 2016 B1
9452297 Mohamed et al. Sep 2016 B2
9456869 Zarins et al. Oct 2016 B2
9463066 Deem et al. Oct 2016 B2
9468497 Zarins et al. Oct 2016 B2
9474563 Zarins et al. Oct 2016 B2
9480991 Baym et al. Nov 2016 B2
9486270 Zarins et al. Nov 2016 B2
9486638 Chornenky et al. Nov 2016 B2
9498491 Black, Sr. Nov 2016 B2
9498638 Ruetenik Nov 2016 B2
9498639 Anderson et al. Nov 2016 B2
9510931 Hotter et al. Dec 2016 B2
9526918 Kruip Dec 2016 B2
9532832 Ron Edoute et al. Jan 2017 B2
9554935 Ingimundarson et al. Jan 2017 B2
9556243 Leach et al. Jan 2017 B2
9603637 Northcutt et al. Mar 2017 B2
9610443 Dean et al. Apr 2017 B1
9610459 Burnett et al. Apr 2017 B2
9612308 Weinberg et al. Apr 2017 B2
9630001 Kronberg et al. Apr 2017 B2
9630004 Rajguru et al. Apr 2017 B2
9636174 Zarins et al. May 2017 B2
9656096 Pilla May 2017 B2
9662183 Lowe et al. May 2017 B2
9669074 Paz Garcia et al. Jun 2017 B2
9675413 Deem et al. Jun 2017 B2
9684074 Schrank et al. Jun 2017 B2
9694193 Van Bree et al. Jul 2017 B2
9694194 Ron Edoute et al. Jul 2017 B2
9707035 Zarins et al. Jul 2017 B2
9724308 Paukshto et al. Aug 2017 B2
9724534 Jacobson et al. Aug 2017 B2
9726738 Weinberg et al. Aug 2017 B2
9727764 Hassler et al. Aug 2017 B2
9730946 Lin et al. Aug 2017 B2
9731132 Deem et al. Aug 2017 B2
9735629 Wagman et al. Aug 2017 B2
9743983 Levin et al. Aug 2017 B2
9746407 Bernardi et al. Aug 2017 B2
9757192 Levin et al. Sep 2017 B2
9757193 Zarins et al. Sep 2017 B2
9757583 Mohamed et al. Sep 2017 B2
9757584 Burnett Sep 2017 B2
9758806 Woodell-May et al. Sep 2017 B2
9776014 Neuman et al. Oct 2017 B2
9795500 Ingimundarson et al. Oct 2017 B2
9796609 Holland Oct 2017 B2
9801905 Mohamed et al. Oct 2017 B2
20010007937 MacKin Jul 2001 A1
20010027278 Kaufman et al. Oct 2001 A1
20010031906 Ishikawa et al. Oct 2001 A1
20010031986 Hauck Oct 2001 A1
20010041820 Woo Nov 2001 A1
20010044643 Litovitz Nov 2001 A1
20020022863 Hauck Feb 2002 A1
20020034796 Shastri et al. Mar 2002 A1
20020035358 Wang Mar 2002 A1
20020052634 March May 2002 A1
20020086842 Plank et al. Jul 2002 A1
20020091850 Perholtz et al. Jul 2002 A1
20020147380 Ardizzone Oct 2002 A1
20020165583 Tepper et al. Nov 2002 A1
20030018368 Ansarinia Jan 2003 A1
20030023283 McDaniel Jan 2003 A1
20030028072 Fischell et al. Feb 2003 A1
20030050527 Fox et al. Mar 2003 A1
20030083537 Ardizzone May 2003 A1
20030093028 Spiegel May 2003 A1
20030095022 Boynton et al. May 2003 A1
20030099979 Ohtani et al. May 2003 A1
20030125661 Yerushalmy Jul 2003 A1
20030125769 Brighton Jul 2003 A1
20030130709 D.C. et al. Jul 2003 A1
20030158583 Burnett et al. Aug 2003 A1
20030158585 Burnett Aug 2003 A1
20030163168 Hauck Aug 2003 A1
20030164761 Levinzon Sep 2003 A1
20030171640 Canedo Sep 2003 A1
20030176895 Hauck Sep 2003 A1
20030181791 Thomas et al. Sep 2003 A1
20030195594 Litovitz Oct 2003 A1
20030211084 Brighton et al. Nov 2003 A1
20040005297 Connelly et al. Jan 2004 A1
20040006373 Brighton et al. Jan 2004 A1
20040054379 Carroll et al. Mar 2004 A1
20040073260 Brighton Apr 2004 A1
20040073269 Carroll et al. Apr 2004 A1
20040077923 Frimerman et al. Apr 2004 A1
20040106843 Ardizzone et al. Jun 2004 A1
20040122281 Fischell et al. Jun 2004 A1
20040138709 Brighton Jul 2004 A1
20040138722 Carroll et al. Jul 2004 A1
20040176803 Whelan et al. Sep 2004 A1
20040176805 Whelan et al. Sep 2004 A1
20040176806 Markoll Sep 2004 A1
20040210254 Burnett et al. Oct 2004 A1
20040230224 Gordon Nov 2004 A1
20040241311 Baianu et al. Dec 2004 A1
20040267333 Kronberg Dec 2004 A1
20050005120 Kahn et al. Jan 2005 A1
20050049640 Gurtner et al. Mar 2005 A1
20050059153 George et al. Mar 2005 A1
20050065394 Spiegel Mar 2005 A1
20050084962 Simon Apr 2005 A1
20050124847 Ardizzone et al. Jun 2005 A1
20050134265 Watkins et al. Jun 2005 A1
20050148807 Salkinder et al. Jul 2005 A1
20050154426 Boveja et al. Jul 2005 A1
20050165460 Erfan Jul 2005 A1
20050177203 Brighton et al. Aug 2005 A1
20050182287 Becker Aug 2005 A1
20050187423 Ardizzone et al. Aug 2005 A1
20050197522 Pilla Sep 2005 A1
20050198812 Schuster et al. Sep 2005 A1
20050215842 Pilla et al. Sep 2005 A1
20050222625 Laniado et al. Oct 2005 A1
20050228209 Schneider et al. Oct 2005 A1
20050251229 Pilla et al. Nov 2005 A1
20050259373 Hoopes Nov 2005 A1
20050267355 Parker Dec 2005 A1
20050288744 Pilla et al. Dec 2005 A1
20060009825 Chiriaev et al. Jan 2006 A1
20060024822 Chang et al. Feb 2006 A1
20060030896 Simon et al. Feb 2006 A1
20060030906 Carroll Feb 2006 A1
20060051328 Johnson Mar 2006 A1
20060057693 Simon Mar 2006 A1
20060085049 Cory et al. Apr 2006 A1
20060094112 Babalola et al. May 2006 A1
20060094924 Riehl May 2006 A1
20060129022 Venza et al. Jun 2006 A1
20060161226 McMickle Jul 2006 A1
20060190043 Brighton et al. Aug 2006 A1
20060205993 Fischell et al. Sep 2006 A1
20060206174 Honeycutt et al. Sep 2006 A1
20060212077 Pilla et al. Sep 2006 A1
20060235473 Brighton Oct 2006 A1
20060240316 Martinez Oct 2006 A1
20060245217 Kirbie et al. Nov 2006 A1
20060258896 Haber et al. Nov 2006 A1
20060271131 Passy et al. Nov 2006 A1
20060293724 Kronberg et al. Dec 2006 A1
20070014055 Ness Jan 2007 A1
20070021645 Zimmerman Jan 2007 A1
20070026514 Pilla et al. Feb 2007 A1
20070027355 Riehl et al. Feb 2007 A1
20070030176 Sanchez-Olea et al. Feb 2007 A1
20070038252 Carroll Feb 2007 A1
20070039211 Pichler Feb 2007 A1
20070043254 DeMarco Feb 2007 A1
20070060477 Pedersen et al. Mar 2007 A1
20070060954 Cameron et al. Mar 2007 A1
20070060981 Pille et al. Mar 2007 A1
20070065420 Johnson Mar 2007 A1
20070078292 Markov et al. Apr 2007 A1
20070104694 Quijano et al. May 2007 A1
20070105769 Simon May 2007 A1
20070139167 Gilson et al. Jun 2007 A1
20070149901 Gordon et al. Jun 2007 A1
20070173904 Pilla Jul 2007 A1
20070203389 Bergman Aug 2007 A1
20070203390 Rohan et al. Aug 2007 A1
20070208249 Kumar Sep 2007 A1
20070208385 Carroll et al. Sep 2007 A1
20070212538 Niu Sep 2007 A1
20070282156 Konings Dec 2007 A1
20070288072 Pascual-Leone et al. Dec 2007 A1
20070299472 Brighton Dec 2007 A1
20080015463 Goldstein Jan 2008 A1
20080021327 El-Bialy et al. Jan 2008 A1
20080039901 Kronberg et al. Feb 2008 A1
20080058793 Pilla et al. Mar 2008 A1
20080077193 Bow et al. Mar 2008 A1
20080092435 Bzdek et al. Apr 2008 A1
20080097142 Savage Apr 2008 A1
20080125617 Puchek May 2008 A1
20080132971 Pille et al. Jun 2008 A1
20080140155 Pilla et al. Jun 2008 A1
20080200749 Zheng et al. Aug 2008 A1
20080208284 Rezai et al. Aug 2008 A1
20080208287 Palermo et al. Aug 2008 A1
20080215113 Pawlowicz Sep 2008 A1
20080215116 Brighton Sep 2008 A1
20080217263 Higgins et al. Sep 2008 A1
20080228185 Vasta et al. Sep 2008 A1
20080269838 Brighton et al. Oct 2008 A1
20080280169 Niu et al. Nov 2008 A1
20080280826 O'Connor Nov 2008 A1
20080287730 Spiegel Nov 2008 A1
20080288035 Gill et al. Nov 2008 A1
20080294269 Fell Nov 2008 A1
20080306325 Burnett et al. Dec 2008 A1
20090018613 Brighton Jan 2009 A1
20090030476 Hargrove Jan 2009 A1
20090043188 Rauscher Feb 2009 A1
20090062885 Brighton et al. Mar 2009 A1
20090099623 Bentwich Apr 2009 A1
20090104160 Young et al. Apr 2009 A1
20090105781 Brighton Apr 2009 A1
20090131739 Shalev May 2009 A1
20090132010 Kronberg May 2009 A1
20090156884 Schneider et al. Jun 2009 A1
20090163762 Setti et al. Jun 2009 A1
20090206882 Patterson Aug 2009 A1
20090206883 Patterson Aug 2009 A1
20090206907 Patterson Aug 2009 A1
20090216068 Thomas Aug 2009 A1
20090227829 Burnett et al. Sep 2009 A1
20090227831 Burnett et al. Sep 2009 A1
20090234179 Burnett et al. Sep 2009 A1
20090234417 Pastena et al. Sep 2009 A1
20090240310 Kennedy Sep 2009 A1
20090287126 Skahan et al. Nov 2009 A1
20090326315 Nishi et al. Dec 2009 A1
20090326602 Glukhovsky et al. Dec 2009 A1
20100004500 Gliner et al. Jan 2010 A1
20100005571 Moss et al. Jan 2010 A1
20100010288 Von Ohlsen et al. Jan 2010 A1
20100049262 Puchek Feb 2010 A1
20100057655 Jacobson et al. Mar 2010 A1
20100075211 Martinez Mar 2010 A1
20100082079 Skahan et al. Apr 2010 A1
20100121407 Pfaff et al. May 2010 A1
20100160712 Burnett et al. Jun 2010 A1
20100160999 Epstein et al. Jun 2010 A1
20100168501 Burnett et al. Jul 2010 A1
20100179373 Pille et al. Jul 2010 A1
20100185041 Lee Jul 2010 A1
20100197993 Vasishta Aug 2010 A1
20100204538 Burnett et al. Aug 2010 A1
20100210893 Pilla Aug 2010 A1
20100221346 Plank et al. Sep 2010 A1
20100222629 Burnett et al. Sep 2010 A1
20100222631 Pilla Sep 2010 A1
20100239544 Simon Sep 2010 A1
20100262052 Lunau et al. Oct 2010 A1
20100298624 Becker Nov 2010 A1
20110004261 Sham et al. Jan 2011 A1
20110021863 Burnett et al. Jan 2011 A1
20110065976 Chornenky et al. Mar 2011 A1
20110065977 Sham et al. Mar 2011 A1
20110105959 O'Connor May 2011 A1
20110112352 Pilla et al. May 2011 A1
20110112522 Wetling May 2011 A1
20110118852 Evans May 2011 A1
20110124717 O'Connor May 2011 A1
20110130618 Ron Edoute et al. Jun 2011 A1
20110152598 Pilla et al. Jun 2011 A1
20110160811 Walker Jun 2011 A1
20110184223 Peterchev et al. Jul 2011 A1
20110190849 Faltys et al. Aug 2011 A1
20110207989 Pilla et al. Aug 2011 A1
20110213195 Kraus et al. Sep 2011 A1
20110217775 Kronberg et al. Sep 2011 A1
20110224480 Weinstock Sep 2011 A1
20110282412 Glukhovsky et al. Nov 2011 A1
20110288611 Lunau et al. Nov 2011 A1
20110295339 Carroll Dec 2011 A1
20120016442 Brighton et al. Jan 2012 A1
20120038441 Wilson et al. Feb 2012 A1
20120059287 El-Bialy et al. Mar 2012 A1
20120078328 Vancraeyenest et al. Mar 2012 A1
20120089201 Pilla Apr 2012 A1
20120101327 Dissing et al. Apr 2012 A1
20120101544 Hoberman et al. Apr 2012 A1
20120116149 Pilla et al. May 2012 A1
20120135390 Clyne et al. May 2012 A1
20120135392 El-Bialy et al. May 2012 A1
20120143285 Wang et al. Jun 2012 A1
20120149968 Brighton Jun 2012 A1
20120172653 Chornenky et al. Jul 2012 A1
20120184800 Brighton Jul 2012 A1
20120215281 Neuman Aug 2012 A1
20120245403 Martinez Sep 2012 A1
20120253101 Wang et al. Oct 2012 A1
20120265048 Biggs et al. Oct 2012 A1
20120302821 Burnett Nov 2012 A1
20120316482 Karim Dec 2012 A1
20120330090 Sham et al. Dec 2012 A1
20130013339 Goldman et al. Jan 2013 A1
20130035539 Kornstein Feb 2013 A1
20130072746 Burnett et al. Mar 2013 A1
20130085317 Feinstein Apr 2013 A1
20130158456 Skahan et al. Jun 2013 A1
20130158634 Ron Edoute et al. Jun 2013 A1
20130165829 Carroll Jun 2013 A1
20130171094 Lin et al. Jul 2013 A1
20130178425 Higgins et al. Jul 2013 A1
20130218235 Pilla et al. Aug 2013 A9
20130238061 Ron Edoute et al. Sep 2013 A1
20130238062 Ron Edoute et al. Sep 2013 A1
20130245358 Johnson et al. Sep 2013 A1
20130261374 Elder Oct 2013 A1
20130267003 Goodwin et al. Oct 2013 A1
20130267020 Goodwin et al. Oct 2013 A1
20130274540 Pilla et al. Oct 2013 A1
20130288260 Rubin et al. Oct 2013 A1
20130289416 Feferberg Oct 2013 A1
20130293327 Wilson et al. Nov 2013 A1
20130296940 Northcutt et al. Nov 2013 A1
20130317282 Ron Edoute et al. Nov 2013 A1
20130344559 Engeberg et al. Dec 2013 A1
20140023983 Lowe et al. Jan 2014 A1
20140024882 Chornenky et al. Jan 2014 A1
20140046115 Pilla Feb 2014 A1
20140046117 Pilla Feb 2014 A1
20140046232 Sham et al. Feb 2014 A1
20140046423 Rajguru et al. Feb 2014 A1
20140066837 Moy Mar 2014 A1
20140081070 Paukshto et al. Mar 2014 A1
20140114382 Kim Apr 2014 A1
20140148870 Burnett May 2014 A1
20140155799 Skahan et al. Jun 2014 A1
20140163304 Burnett et al. Jun 2014 A1
20140207018 Weinstock Jul 2014 A1
20140207040 Ingimundarson et al. Jul 2014 A1
20140207041 Ingimundarson et al. Jul 2014 A1
20140213843 Pilla et al. Jul 2014 A1
20140213844 Pilla et al. Jul 2014 A1
20140221726 Pilla et al. Aug 2014 A1
20140228620 Vasishta Aug 2014 A1
20140249354 Anderson et al. Sep 2014 A1
20140249355 Martinez Sep 2014 A1
20140303425 Pilla et al. Oct 2014 A1
20140322292 Lin et al. Oct 2014 A1
20140342300 Schnaitter Nov 2014 A1
20140342428 Goodwin et al. Nov 2014 A1
20140343642 Lauer Nov 2014 A1
20140350649 Kronberg et al. Nov 2014 A1
20150005672 Gangwish et al. Jan 2015 A1
20150010499 Lin et al. Jan 2015 A1
20150025299 Ron Edoute et al. Jan 2015 A1
20150094521 Neuman et al. Apr 2015 A1
20150099804 Lin et al. Apr 2015 A1
20150107774 Lee Apr 2015 A1
20150141736 Tsai et al. May 2015 A1
20150151136 Ruetenik Jun 2015 A1
20150174166 Giampapa Jun 2015 A1
20150196771 Pilla et al. Jul 2015 A1
20150202454 Burnett Jul 2015 A1
20150217107 Walker Aug 2015 A1
20150217125 Chornenky et al. Aug 2015 A1
20150217126 Pilla Aug 2015 A1
20150258346 Cadossi et al. Sep 2015 A1
20150273221 Manning et al. Oct 2015 A1
20150297910 Dimino et al. Oct 2015 A1
20150306412 Durschmidt Oct 2015 A1
20150315539 Villanueva et al. Nov 2015 A1
20150320697 O'Connor Nov 2015 A1
20150328033 Ingimundarson et al. Nov 2015 A1
20150328034 Ingimundarson et al. Nov 2015 A1
20150328476 Anderson et al. Nov 2015 A1
20150342661 Ron Edoute Dec 2015 A1
20160000870 Higgins et al. Jan 2016 A1
20160008024 Payne et al. Jan 2016 A1
20160015432 Northcutt et al. Jan 2016 A1
20160015545 Petursson Jan 2016 A1
20160022989 Pfeifer Jan 2016 A1
20160038753 Chornenky et al. Feb 2016 A1
20160051827 Ron Edoute et al. Feb 2016 A1
20160067103 Anthony Mar 2016 A1
20160067515 Burnett et al. Mar 2016 A1
20160067517 Burnett Mar 2016 A1
20160074670 Mohamed et al. Mar 2016 A1
20160074671 Burnett et al. Mar 2016 A1
20160121135 Pilla May 2016 A1
20160129273 Park May 2016 A1
20160129274 Park May 2016 A1
20160129284 Mikus May 2016 A1
20160145571 Giampapa May 2016 A1
20160151416 Lin et al. Jun 2016 A1
20160151646 Bonutti et al. Jun 2016 A1
20160193466 Burnett Jul 2016 A1
20160206876 Rajguru et al. Jul 2016 A1
20160228721 Mohamed et al. Aug 2016 A1
20160228723 Mohamed et al. Aug 2016 A1
20160235983 Berman et al. Aug 2016 A1
20160246944 Jain et al. Aug 2016 A1
20160306042 Schrank et al. Oct 2016 A1
20160313159 Appel et al. Oct 2016 A1
20160317828 Sham et al. Nov 2016 A1
20160331990 Mohamed et al. Nov 2016 A1
20160339261 Mletzko Nov 2016 A1
20160346016 Northcutt Dec 2016 A1
20160346561 Ron Edoute et al. Dec 2016 A1
20160354446 Paz Garcia et al. Dec 2016 A1
20160372362 Signamarcheix et al. Dec 2016 A1
20170000536 Tacktill Jan 2017 A1
20170001025 Schwarz et al. Jan 2017 A1
20170001201 Baym et al. Jan 2017 A1
20170027858 Borgens et al. Feb 2017 A1
20170028184 Godden et al. Feb 2017 A1
20170030188 Lehr Feb 2017 A1
20170039404 Hassler et al. Feb 2017 A1
20170043177 Ron Edoute et al. Feb 2017 A1
20170050019 Ron Edoute et al. Feb 2017 A1
20170056644 Chahine et al. Mar 2017 A1
20170071977 Mohamed et al. Mar 2017 A1
20170072210 Gangwish et al. Mar 2017 A1
20170080245 Dimino et al. Mar 2017 A1
20170087367 Weisend Mar 2017 A1
20170113059 Fisher Apr 2017 A1
20170113060 Anderson et al. Apr 2017 A1
20170128538 Toler et al. May 2017 A1
20170151442 Walborn Jun 2017 A1
20170152500 Seo et al. Jun 2017 A1
20170157318 Balakrishnan Jun 2017 A1
20170165496 Pilla et al. Jun 2017 A1
20170173076 Greco et al. Jun 2017 A1
20170173295 Sanderson et al. Jun 2017 A1
20170173347 Schwarz et al. Jun 2017 A1
20170202509 Sanderson et al. Jul 2017 A1
20170209717 Bonutti et al. Jul 2017 A1
20170225005 Burnett et al. Aug 2017 A1
20170226463 Kronberg et al. Aug 2017 A1
20170246481 Mishelevich Aug 2017 A1
20170252574 Cabrerizo et al. Sep 2017 A1
20170266443 Rajguru et al. Sep 2017 A1
20170266458 Pilla Sep 2017 A1
20170266459 Mohamed et al. Sep 2017 A1
20170291039 Jacobson et al. Oct 2017 A1
20170295778 Jiles et al. Oct 2017 A1
20170298340 Goodwin et al. Oct 2017 A1
20170298341 Goodwin et al. Oct 2017 A1
20170304642 Ron Edoute et al. Oct 2017 A1
20170319250 Whittaker et al. Nov 2017 A1
Foreign Referenced Citations (17)
Number Date Country
1216076 Jun 2002 EP
101219990 Jan 2013 KR
94025257 May 1996 RU
2248229 Mar 2005 RU
WO8301742 May 1983 WO
WO9527533 Oct 1995 WO
WO9611723 Apr 1996 WO
WO9632158 Oct 1996 WO
WO0115774 Mar 2001 WO
WO0209811 Feb 2002 WO
WO2004108208 Dec 2004 WO
WO2005051306 Jun 2005 WO
WO2008070001 Jun 2008 WO
WO2009155516 Dec 2009 WO
WO2010067336 Jun 2010 WO
WO2010149164 Dec 2010 WO
WO2011053607 May 2011 WO
Non-Patent Literature Citations (1)
Entry
PCT Written Opinion/ISR PCT/US2017/061106 (dated Feb. 28, 2018).
Related Publications (1)
Number Date Country
20220294892 A1 Sep 2022 US
Provisional Applications (1)
Number Date Country
62420337 Nov 2016 US
Continuations (1)
Number Date Country
Parent 15809684 Nov 2017 US
Child 17828023 US