Scientific Articles and Abstracts
A wealth of articles on Pulsing Electromagnetic Field therapy (PEMF) is available. Here follow several veterinary articles and many more can be found on our main website
Explaining electromagnetic field therapy
The therapy with pulsating magnetic fields (PEMF) is a relatively new and very effective form of physical therapy. It is not a miracle, but simply a physical (or better. biophysical) modality used in the medical branch and utilized for accelerated therapeutic purposes. The use of PEMF is a very efficient and simple therapy method. By influencing the animal either generally or locally with a magnetic field packed in impulse bundles. the cellular functions can be improved considerably. The pulsating magnetic field has a high biological effectiveness, which is being used in the medical field as a means of therapy as well as in the area of diagnostics. Today we have two basic magnetic therapies, the direct one with a magnetic field that serves as a medium for the inductive production of a current in a special implant. Magnetic fields cannot be absorbed, they can only be shielded against shunting them into strong ferromagnetic materials. Therefore, it is difficult to produce field-free spaces when magnetic fields strike a material. We differentiate between so-called paramagnetic substances in which a bundling or a concentration of magnetic field lines occur, and the so-called diamagnetic substances, in which a decentralization of the field lines results. Air is neutral. The animal's body is only insignificantly diamagnetic and paramagnetic; basically, it is neutral. So whenever field lines impact on the animal organism or on parts of it, they absolutely permeate these areas. Compared to known methods this is the first important discovery. Within the range of magnetic fields, all parts of the body are penetrated completely by the field lines. It is known that the human and animal organism consists of a large number of cells. These cells are functioning electrically. If there is no electrical potential left in the cell, it is no longer viable. These cells have a basic (or rest) potential that is necessary for normal cellular metabolism. Diseased or damaged cells have an altered rest potential. If the ions (electrically charged particles surrounding the cells) move into the area of pulsating magnetic fields, they will be influenced by the rhythm of the pulsation. The rest potential of the cell is proportional to the ion exchange occurring at the cell membrane. The ion exchange is also responsible for the oxygen utilization of the cell. Pulsating magnetic fields can dramatically influence the ion exchange at the cellular level and thereby greatly improve the oxygen utilization of diseased or damaged tissues. The deterioration of the oxygen utilization is known to be a problem in several medical branches, especially delayed healing and arthritis of joints. Thus the wide range of indications are: 1. Orthopedics, traumatology, rheumatology, after-treatment of complicated and simple fractures, wound treatment, burns, and degenerative diseases of the apparatus of support and locomotion. 2. Coronary and circulatory diseases; 3. Disorders of the neurological system. From bibliography and clinical experiments, we know that pulsating magnetic fields are able to reduce pain sensations almost immediately. This is due in part to the increase in the oxygen partial pressure in the terminal tissue and the increase in the local perfusion and velocity of the capillary blood flow alleviating the accumulation of metabolites due to small vascularization and blood flow (transmitted by the sympathetic nervous system). The above mentions the wide area of indications but says nothing of contraindications and side effects. There are no absolute contraindications to magnetic therapy except in cases of haemorrhage or where electrical implants already are in use. In contrast to chemical medicaments, there is no over-dosage, at least within the field range that we are presently using for treatments. Magnetic field powers of maximum 100 gauss are far less than field powers that have negative biological effects. The PEMF therapy is an absolutely heat-less therapy method, not a heat producing method, not a heat producing therapy. Therefore, all implants (except heart pacemakers) can be treated. Our hospital has used PEMF therapy to accelerate the healing of those horses needing pins and bone plates. No damaging heat will be produced in the implants. Furthermore, all implants are antimagnetic. The treatment of fractures can also be applied with a plaster cast because, as mentioned before, magnetic fields permeate all materials. The therapeutic effect of such treatments lasts for approximately six to eight hours. This shows that the majority of all cases at the beginning of a series of treatments daily. Only after five to 10 days can the treatment regime be reduced to one treatment daily or every other day. In very chronic or extremely difficult cases, this treatment may be longer. The wide experience concerning the application of this therapy implies that an alternate solution has been found in accelerating the healing time of many of our common injuries affecting our running horses, as well as possible therapy for those patients who have been resistant to other therapies and those patients injured by the side effects of other therapies.
Drs. James E. Bullock and Kevin J. May of Bullock's Veterinary Hospital
Experience with Pulsating ElectroMagnetic Fields (PEMF) in horse therapy. (Translated from German)
Experience, over a 3-year period treating 290 sport horses with PEMF, justifies the statement that PEMF therapy for horses is a real alternative therapy instead of conventional therapy modalities like corticosteroids, phenylbutazone and other drugs. Compared to experience in human medicine, therapy in horses require shorter treatment intervals. Specifically the good therapy results obtained for diseases of extremities open up ways for additional PEMF indications. Xenophon (2400 years ago) already wrote in one of his works "About the art of horse riding" specific information as how to avoid diseases and injuries at the joints by means of different therapies, to decrease suffering. In German literature we find in the 13th century in Albert Ross' pharmaceutical book a precise description of various horse diseases and their treatments. The development of horses, used for all kind of purposes, to real sport horses were and still are, not without problems for the DVM. Nowadays our sport horses are too early- and to short trained to obtain results for which they are not yet ready, based on their bodies and conditions. This results in various forms of damages dependent on the different uses of horses. Horses are often treated for chronic diseases with various drugs and often training has to be discontinued for weeks or even months. The results of PEMF therapy in veterinary use are objective and can not be any form of placebo effect. Also it was not clear how this form of therapy could be explained according to biophysical therapy methods and only new published works of Altmann and Warnke explained this further. Due to difficulties of using coil applicators for horses special leg-wraps were developed which can be applied without problems at the horse leg, so therapy can be easily done in a short time frame. PEMF is used for the following diseases: Degenerative diseases, acute and chronic inflammations of sheaths and tendons, ligament ruptures, distortions, contusions, chronic joint diseases, delayed wound- healing, diseases of back and lumbar regions. For acute therapy we start out with values of 20-30 Gauss and 5 Hz. Chronic cases with 50 Gauss, 10 Hz and go up in intensity over a 4-5 day therapy period. Treatment time for daily therapy is at least 15 minutes and for twice daily therapy at least 10 minutes each. In case of infected diseases PEMF therapy should be combined with antibiotics. Young horses (up to around 10 years) respond extremely well to PEMF therapy. E.g. a large amount of horses who were treated for arthrosis of phalanges and tarsus, are very successful at various forms of sports without any further treatment. For elderly horses with severe joint and ligament diseases it was partly necessary to have some additional therapy sessions after around 6 months. Many older jumping horses (12-18 years) were treated with phenylbutazone were healed without further need for drugs. Compared to data of human clinical studies it was noticed that horses needed less therapy sessions to obtain results. E.g. for acute inflammations 8 - 10 treatments and for chronic joint diseases, around 12 - 20 treatments. In cases of light to moderate paralysis exercises should be done from day one in combination with therapy. This will prevent significantly set-back in training compared to conventional therapy.
H. Focke DVM, published in "Der Praktische Tierarzt" in Germany
Evaluation of treatment with a pulsed electromagnetic field on wound healing, clinicopathologic variables, and central nervous system activity of dogs.
OBJECTIVE: To evaluate effects of treatment with a pulsed electromagnetic field (PEMF) on healing of open and sutured wounds, clinicopathologic variables, and CNS activity of dogs. ANIMALS: 12 adult female Beagles. PROCEDURE: Open and sutured wounds were created in the skin of the trunk of the dogs. Dogs were divided into 2 groups. One group received PEMF treatment and 1 group served as untreated (control) dogs. The PEMF-treated dogs received treatment twice a day starting the day before surgery and lasting through day 21 after surgery. Wounds were evaluated by use of tensiometry, planimetry, laser Doppler perfusion imaging, and histologic examination. Clinicopathologic variables and electroencephalographic tracings were also evaluated. RESULTS: Use of PEMF treatment resulted in significantly enhanced epithelialization of open wounds 10 and 15 days after surgery. Five days after surgery, wounds of control dogs had a negative value for wound contraction, whereas PEMF-treated wounds had a positive value. The PEMF treatment did not cause significant changes in short-term planimetric, perfusion, tensiometric, histologic, clinicopathologic, or electroencephalographic results. CONCLUSIONS: The PEMF treatment enhanced wound epithelialization in open cutaneous wounds and provided indications of early contraction without significant short-term changes in other variables.
Scardino M. et.al. College of Vet Medicine, Auburn University, Am J Vet Res
The Black Stallion's broken leg treated with PEMF Therapy
"Diamond Night" better known as The Black Stallion broke his leg in several places and most veterinarians would have put him to sleep. Dr. Bullock, saved his life with a daring surgery and used Pulsating Electro Magnetic Field Therapy which completely healed his leg in record time. When a horse breaks a leg, the usual treatment is termination. But when that horse is a well trained movie star, a few more doors are open. Diamond Night, one of three horses who played the title role in the film The Black Stallion, was given new life through the fast action of his trainer, Corky Randall and Dr. James E. Bullock. This five-year-old Arabian stallion was training on Tuesday, June 29 for an upcoming movie. According to trainers, he went up into the air and came down again, losing his footing and continuing to fall onto his right shoulder. They heard a loud crack resembling a rifle shot. When Diamond Night stood up his left front leg was dangling. The Black stallion's trainer immediately called his veterinarian Bullock's veterinary hospital in Newhall, CA. "When I arrived, he (Diamond Night) was standing in a round pen where he had been training," said Dr. Bullock. "X-rays revealed that the leg was shattered at the distal section - a transverse fracture at the distal aspect and numerous pieces at the proximal aspect. The ulna was broken - a transverse fracture through the ulna." After examining the x-rays, Dr. Bullock decided to go ahead and do the surgery. "We knew a bone plate wouldn't work," he said. "The horse had not made any type of the compound fracture through the skin, so we still had a chance as far as infection goes. We stabilized the horse and put a temporary support splint and cast on him and spun the horse up so that he wouldn't put any weight on the leg." This particular spot couldn't be cast because the fracture was about three inches below the elbow, explained Dr. Bullock. He said in order to cast it, one would have to place a joint below the fracture. In this case, he said it would merely act as a fulcrum and that different breaks would usually occur after that. "This is why this type of fracture is rarely attempted," he said. "Also, most horses will not tolerate a sling. Diamond Night is an extremely intelligent horse and did very well in a sling. He used it to rest in and when he was not tired, he stood. We anticipated he would be in a sling for a minimum of six weeks." Dr. Bullock spent all Tuesday night with the owner of a machine shop trying to design the type of apparatus they would need to accomplish the surgery. Assembly of the equipment started at 7:30 Wednesday morning and at 3 o'clock that afternoon, surgery began. The stallion was down for 5 1/2 hours plus a recovery of 2 1/2 hours. "We applied a Kirschner apparatus to the radius to stabilize the fracture," he said. "This may have been done before, but it hadn't been published, so we didn't have a lot to go on." "For the first two days he had the support cast. After that, we just left it open." On Friday, Dr. Bullock started the PEMF therapy. He explained that Diamond Night got two, 30 minute sessions per day. He slid a coil up over the fracture. The magnetic field surrounding the fracture is increased, along with circulation and oxygenation. "PEMF therapy increases oxygenation of the tissue and increases ionic exchange of the bone which potentiates healing." said Dr. Bullock. "The horse has no feeling or sensation of the therapy. But the pain goes away and the fracture can heal. PEMF therapy reduced the time the horse had to spend in a sling." Arrangements were also made with a certified welder to develop a walker for Diamond Night. Dr. Bullock said they walked him while he was still in a sling to prevent problems occurring with the other legs and muscles and subsequent pneumonia. As of July 22nd, X-rays showed the bones healing and that Diamond Night was doing very well.
Evaluation of PEMF on horses
he influence of pulsed low-frequency electromagnetic fields (PEMFs) on bone formation was investigated in studies of the healing process of transcortical holes, bored at the diaphyseal region of metacarpal bones of six adult horses, exposed for 30 days to PEMFs (28 G peak amplitude, 1.3 ms rise time, and 75 Hz repetition rate). A pair of Helmholtz coils, continuously powered by a pulse generator, was applied for 30 days to the left metacarpal bone, through which two holes, of equal diameter and depth, had been bored at the diaphyseal region. Two equal holes, bored at the same level in the right metacarpal and surrounded by an inactive pair of Helmholtz coils, were used as controls. All horses were given an intravenous injection of 25-30 mg/kg of tetracycline chloride on the 15th and again on the 25th day after the operation and were killed 5 days later. The histomorphometric analysis indicated that both the amount of bone formed during 30 days and the mineral apposition rate during 10 days (deduced from the interval between the two tetracycline labels) were significantly greater (p < 0.01 and p < 0.0001, respectively) in the PEMF-treated holes than in the controls. As did a previous investigation, these preliminary findings indicate that PEMFs at low frequency not only stimulate bone repair but also seem to improve the osteogenic phase of the healing process, at least in our experimental conditions.
Institute of Human Anatomy, University of Modena, Italy
Pulsing electromagnetic field therapy in nerve regeneration: an experimental study in the cat
A multidisciplinary approach to the study of peripheral nerve regeneration in the cat has been presented. The purpose of this work has been to determine if pulsing electromagnetic field (PEMF) therapy can enhance peripheral nerve regeneration after injury. In equal groups of animals, two types of pulsing electromagnetic field treatment were compared with untreated controls. All animals underwent quantitative electrophysiologic and morphologic assessment at the area of injury. In addition, muscle fibre sizing in the periphery and retrograde labeling of anterior horn motoneurons with horseradish peroxidase were studied. Results have shown no statistical differences between the groups in electrophysiologic or morphologic parameters. However, in animals treated with a pulse-burst electromagnetic field there was a statistically significant improvement in the labelling and localization of anterior horn cells in the central nervous system. These results indicate that pulse-burst electromagnetic radiation can increase the numbers of motor neurons that re-establish appropriate connections to the periphery after nerve injury.
Orgel MG, O'Brien WJ, Murray H. Plast Reconstr Surg
Effects of pulsed electromagnetic fields on bone healing in a rabbit tibial osteotomy model
OBJECTIVE: The purpose of this study was to determine the effect of pulsed electromagnetic field (PEMF) exposure on healing tibial osteotomies in New Zealand White rabbits. DESIGN: One-millimeter Gigli saw osteotomies were stabilized by external fixation. One day after surgery, rabbits were randomly assigned to receive either no exposure (sham control) or thirty minutes or sixty minutes per day of low-frequency, low-amplitude PEMF. Radiographs were obtained weekly throughout the study. Rabbits were euthanized at fourteen, twenty-one, or twenty-eight days, and tibiae underwent either destructive torsional testing or histologic analysis. To determine the baseline torsional strength and stiffness of rabbit tibiae, eleven normal intact tibiae were tested to failure. RESULTS: Sixty-minute PEMF-treated osteotomies had significantly higher torsional strength than did sham controls at fourteen and twenty-one days postoperatively. Thirty-minute PEMF-treated osteotomies were significantly stronger than sham controls only after twenty-one days. Normal intact torsional strength was achieved by fourteen days in the sixty-minute PEMF group, by twenty-one days in the thirty-minute PEMF group, and by twenty-eight days in the sham controls. Maximum fracture callus area correlated with the time to reach normal torsional strength. CONCLUSION: In this animal model, low-frequency, low-amplitude PEMF significantly accelerated callus formation and osteotomy healing in a dose-dependent manner.
Fredericks D. et.al. Uni of Iowa College of Medicine, J Orthop Trauma
Pulsed electromagnetic fields simultaneously induce osteogenesis and upregulate transcription of bone morphogenetic proteins 2 and 4 in rat osteoblasts in vitro
Pulsed electromagnetic fields (PEMF) are successfully employed in the treatment of a variety of orthopaedic conditions, particularly delayed and nonunion fractures. In this study, we examined PEMF effects on in vitro osteogenesis by bone nodule formation and on mRNA expression of bone morphogenetic proteins 2 and 4 by reverse-transcriptase polymerase chain reaction (RT-PCR) in cultured rat calvarial osteoblasts. PEMF exposure induced a significant increase in both the number (39% over unexposed controls) and size (70% larger compared to unexposed controls) of bone-like nodules formed. PEMF also induced an increase in the levels of BMP-2 and BMP-4 mRNA in comparison to controls. This effect was directly related to the duration of PEMF exposure. This study shows that clinically applied PEMF have a reproducible osteogenic effect in vitro and simultaneously induce BMP-2 and -4 mRNA transcription. This supports the concept that the two effects are related.
Bodamyali T. et.al. Postgraduate Medicine, Uni of Bath, UK Biochem Biophys Res Commun
Effects of electromagnetic stimulation on the functional responsiveness of isolated rat osteoclasts
We report the effects of pulsed electromagnetic fields (PEMFs) on the responsiveness of osteoclasts to cellular, hormonal, and ionic signals. Osteoclasts isolated from neonatal rat long bones were dispersed onto either slices of devitalised cortical bone (for the measurement of resorptive activity) or glass coverslips (for the determination of the cytosolic free Ca2+ concentration, [Ca2+]). Osteoclasts were also cocultured on bone with osteoblastlike, UMR-106 cells. Bone resorption was quantitated by scanning electron microscopy and computer-assisted morphometry. PEMF application to osteoblast-osteoclast cocultures for 18 hr resulted in a twofold stimulation of bone resorption. In contrast, resorption by isolated osteoclasts remained unchanged in the presence of PEMFs, suggesting that osteoblasts were necessary for the PEMF-induced resorption simulation seen in osteoblast-osteoclast cocultures. Furthermore, the potent inhibitory action of the hormone calcitonin on bone resorption was unaffected by PEMF application. However, PEMFs completely reversed another quite distinct action of calcitonin on the osteoclast: its potent inhibitory effect on the activation of the divalent cation-sensing (or Ca2+) receptor. For these experiments, we made fura 2-based measurements of cytosolic [Ca2+] in single osteoclasts in response to the application of a known Ca2+ receptor agonist, Ni2+. We first confirmed that activation of the osteoclast Ca2+ receptor by Ni2+ (5 mM) resulted in a characteristic monophasic elevation of cytosolic [Ca2+]. As shown previously, this response was attenuated strongly by calcitonin at concentrations between 0.03 and 3 nM but remained intact in response to PEMFs. PEMF application, however, prevented the inhibitory effect of calcitonin on Ni2+-induced cytosolic Ca2+ elevation. This suggested that the fields disrupted the interaction between the calcitonin and Ca2+ receptor systems. In conclusion, we have shown that electromagnetic fields stimulate bone resorption through an action on the osteoblast and, by abolishing the inhibitory effects of calcitonin, also restore the responsiveness of osteoclasts to divalent cations.
Shankar V. et.al. Center for Osteoporosis and Skeletal Aging, Philadelphia J Cell Physiol
Pulsed electromagnetic fields in experimental cutaneous wound healing in rats
Electromagnetic fields are now being used in many diseases such as osseous, ligamental, cartilaginous, or nervous reparation, diabetes, and myocardial or cerebral ischemia. Although many publications show the usefulness of magneto-therapy, discrepancies exist about the utility of electromagnetic fields in skin wound healing. The objective of this work was to study the effect of pulsed electromagnetic fields on wound healing in rats. Twenty-two male Wistar rats were used; a circular lesion was made in the back of each animal. They were divided into three groups: group C (control) with sham treatment (n = 8), group NF, treated with topical nitrofurazone solution (n = 7), and group PEMF, treated with pulsed electromagnetic fields of 20 mT (n = 7). The treatments were 35 minutes twice a day. The absolute and relative values of the area and perimeter of the wounds showed significantly lower values in the PEMF group at days 7, 14, and 21 compared with those in group C (p < 0.01, analysis of variance), whereas the PEMF group showed significantly lower values at day 21 only compared with the NF group (p < 0.01, analysis of variance). The results suggest a significant beneficial stimulation in the wound healing process in rats treated with PEMF, which could lead to the development of a practical tool for research and clinical use.
Patino O. et.al. Postgraduate Reconstr. and Plastic Surgery, Uni del Salvador J Burn Care Rehabil
Enhancement of functional recovery following a crush lesion to the rat sciatic nerve by exposure to pulsed electromagnetic fields
Previous studies showed that exposure to pulsed electromagnetic fields (PEMF) produced a 22% increase in the axonal regeneration rate during the first 6 days after crush injury in the rat sciatic nerve. We used the same injury model to assess the effect on functional recovery. The animals were treated with whole body exposure to PEMF (0.3 mT, repetition rate 2 Hz) for 4 h/day during Days 1-5 while held in plastic restrainers. Functional recovery was serially assessed up to Postinjury Day 43 using recently described video imaging of the 1-5 toe spread and the gait-stance duration. Footprint analysis was also used with calculation of a sciatic function index. Those animals treated with PEMF had improved functional recovery, as compared to sham controls, using the tests for video 1-5 toe spread and gait-stance duration (P = 0.001 and P = 0.081, respectively). This effect was found throughout the 43-day recovery period. No effect was found using the sciatic function index. This study confirms that functional recovery after nerve crush lesion is accelerated by PEMF and has broad implications for the clinical use of these fields in the management of nerve injuries.
Walker J. et.al. Orthopaedic Surgery, Uni of Kentucky Exp Neurol
Effect of PEMF on fresh fracture-healing in rat tibia
The present experiment was designed to find out whether PEMF can act as a healing agent on induced fracture of rat tibia. Eighty rats were taken for this experiment. Under general anaesthesia mid-shaft of tibia and fibula of all rats were osteotomied, Intramedullary nailing was done for proper alignment of the fractured fragments. The animals were then divided into two groups: group-1 and Group-II. Each group contained forty animals. Out of these forty animals twenty were treated as experimental and twenty as control. From the third day of osteotomy, PEMF was applied to experimental rats around the osteotomy sites for a period of nine hours a day. PEMF was not applied to the control rats. The animals of group-1 and group-II were sacrificed after applied one week and three weeks of PEMF, respectively. Radiological and microscopical examination of the callus were performed. Gross and microscopic measurements of the callus were statistically analysed. The growth of callus was taken as a criterion of fracture healing. The results of the present experiment revealed significant enhancement of fracture healing in group-I. The results of the radiological evaluation of group-II experimental animals were also consistent with the morphological analysis. It was concluded that healing of fractured rat tibia was enhanced by the application of PEMF and this effect of PEMF was more pronounced at the end of third week.
Sarker A. et.al. Dep. of Path., Okayama Uni, Japan. Bangladesh Med Res Counc Bull