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A non-operative salvage of surgically-resistant pseudarthroses and non-unions by pulsing electromagnetic fields. A preliminary report.

This report documents, for the first time, to the authors' knowledge, the therapeutic use in humans of low energy, electromagnetic fields pulsing in the extremely low frequency (E.L.F.) range. These fields, established outside the body, were used to treat congenital and acquired pseudarthroses and non-unions. Energy of this type appears to affect biological processes, not through heat production, but through electrically-induced changes in the environment of cells within the organism. Of the 29 patients included in the study, 17 had experienced at least one failure of surgical repair and, in each of these, amputation had been recommended. The overall success rate, including those patients treated with inadequate pulse characteristics and those who failed to follow the protocol, was in excess of 70 per cent. Improvements in the specificity of pulse characteristics hold promise for increasing the rate of success. The simple, clinical methodology, which is conducted on an out-patient basis, appears to be both safe and effective. It can be applied with or without surgery. This approach requires additional controlled investigations before it is ready for general use in the orthopaedic community. The indications for amputation of surgically-resistant pseudarthroses, however, should be reassessed. The principles and technology, which have been established during this endeavor, may have physiologic and practical significance for processes other than pseudarthrosis and non-union.

Adolescent

Experimental regeneration in peripheral nerves and the spinal cord in laboratory animals exposed to a pulsed electromagnetic field.

Peripheral nerve section and suture was performed in 132 rats. Postoperatively half the animals were exposed to a pulsed electromagnetic field each day and half were kept as controls. Nerve conduction studies, histology and nerve fibre counts all indicated an increased rate of regeneration in the treated animals. A similar controlled study of spinal cord regeneration following hemicordotomy in cats has been started, and preliminary results indicate that when the animals are sacrificed three months after the hemicordotomy, the pulsed electromagnetic therapy has induced nerve fibre regeneration across the region of the scar.

Animals

The Effect of Pulsed Electromagnetic Field on Pain and Foot Function Index in Patients With Plantar Fasciitis.

The plantar fascia is a thick band of connective tissue that originates from the heel, and its inflammation is the most common cause of heel pain in adults. The Pulsed Electromagnetic Field (PEMF) is a non-invasive modality in the field of physiotherapy. This study aimed to determine the effects of PEMF on pain scores and the Foot Function Index (FFI) in patients with plantar fasciitis (PF). In this clinical trial study, 40 patients with PF, aged between 20 and 68 years, were randomly assigned in a block design into two groups: the Conventional Physiotherapy (CP) group and the CP plus PEMF (CPP) group. The Numerical Pain Rating Scale (NPRS) and the FFI questionnaire were used to assess the pain score (morning and evening pain) and foot function, respectively. Assessments were conducted before the study, at the tenth session of the CP and CPP groups, and 4 weeks later. The study variables in both the CP and CPP groups changed significantly (p&#x2009;<&#x2009;0.05). In comparing the results between the two groups, the reduction in evening pain scores in the CPP group was significant compared to the CP group (p&#x2009;<&#x2009;0.05). In comparison, there was no significant difference in morning pain scores between the two groups. The FFI score in the CPP group significantly decreased compared to the CP group. Both CP and CPP are effective in reducing pain and the FFI in patients with PF. The addition of PEMF to CP demonstrates a more significant effect on reducing evening pain and somewhat on reducing the FFI in patients compared to CP alone. However, it did not have an additional effect on reducing morning pain. Bioelectromagnetics. 00:00-00, 2026. &#xa9; 2026 Bioelectromagnetics Society.

Humans

[External interference of cardiac pacemakers (author's transl)].

The pacemaker patient is faced with potential origins of interference to the pacemaker function in his daily life, at his working place and during medical-therapeutic interventions. Technical faults in the electronic circuit induced by external sources can be neglected. Malfunctions of synchronized cardiac pacemakers may occur in the presence of electrical signals similar to the intracardiac ECG (e.g. nerve stimulators) or by the influence of high energy electrical field (e.g. pulsed electromagnetic fields). Technical improvements like metalshielding of the unit, electronic filtering components and automatic conversion to fixed rate stimulation increase the reliability to a high degree.

Activities of Daily Living

Changes in the blood count of growing rats irradiated with a microwave pulse field.

A group of 20 male rats of mean initial body weight of 65.53 g were irradiated for 7 wk (5 days per wk, 4 hr per day) with an electromagnetic pulse field of the following parameters: working frequency 2,736.5 MHz; repeated frequency 395 Hz; pulse width 2.6 musec; vertical polarization; mean power density 24.4 mW/cm2; accuracy of measuring +/- 6%. The rectal temperature of experimental animals increased during irradiation by a maximum of 0.5 degrees C. Blood was taken before irradiation, at the end of the 1st, 3rd, 5th, and 7th wk of irradiation, and at the end of the 1st, 2nd, 6th, and 10th wk after irradiation was completed. The parameters under study included the hematocrit value; number of leukocyte differential count in both absolute and relative proportions; activity of alkaline phosphatase in neutrophil leukocytes; and body weight increase. The results were compared with parallel data obtained from a control group of 20 animals and evaluated by Student's t test at a significance level of 1%. In the second half of the irradiation period the experimental animals exhibited significantly lower mean hematocrit values, lower numbers of leukocytes, and lower absolute numbers of lymphocytes. These changes disappeared gradually within 10 wk after completed irradiation. Activity of alkaline phosphatase in neutrophil leukocytes was significantly increased in the 1st wk of irradiation and dropped transiently after the irradiation. In the post-irradiation interval experimental animals displayed significant decline in rate of body weight increase. The level of the other examined parameters did not differ from the controls.

Animals

Intracellular hyperthermia. A biophysical approach to cancer treatment via intracellular temperature and biophysical alterations.

This paper introduces a new multi-disciplinary "intracellular" biophysical treatment of cancer. The basic concept uses locally induced heat energy after tumor phagocytosis of submicron particles whose composition permits magnetic excitation. The key to this process is the utilization of the cancer cell membrane to contain the energy within the cancer cell. Any magnetic or electric dipole contained within or introduced into the cell, or that is capable of being produced by an external field, can be used. Submicron particles are colloidally suspended, injected intravenously and are phagocytized by cancer cells. Application of an external high frequency or pulsed electromagnetic field then raises the particles' temperature thus generating intracellular heat in precise increments. This results in selective thermal destruction of cancer cells with little effect on normal cells. Experimental evidence is presented showing tumor cell destruction in spontaneous mammary tumors in Sprague Dawley rats. In addition, we suggest that certain biophysical properties are altered within the cancer cells and could be used to enhance this effect. Specific radioisotopes or tumor specific antibodies bound to particles or chemotherapeutic microspheres increase cancer cell sensitivity and affinity for these particles. This "intracellular" treatment of cancer has a wide potential range of applications.

Animals

[Normal development of the fruitfly Drosophila in VLF magnetic fields (author's transl)].

Attempts to substantiate irreversible actions of a variety of magnetic fields on the fruitfly, Drosophila melanogaster, have been successful and unsuccessful in about equal numbers. The most conspicuous mutagenic effects apparently induced by pulsed HF-fields failed to appear under continuous electromagnetic irradiation. This seems to correlate the observed damage with the VLF-components of the pulsed fields. The present investigation is motivated by the occurrence of these components both in the atmosphere and in the vicinity of electrical appliances. A strain of normally viable wild type males and subnormally viable Attached X y w females was used in which the yield, and the sex ratio, of the progeny indicate, respectively, the extent of developmental damage and of sex-linked recessive lethal mutation induced by the exposure of detrimental conditions. Evaluation of 73,800 flies from subsequent generations of a control group and two test groups raised in steady, or rotating, homogeneous 9.6 kHz magnetic fields of about 2.5 G did not reveal any developmental or hereditarc load in the test groups. (Pressman 1970; Mittler 1973).

Animals

The effect of low frequency magnetic fields on the healing of the osteotomized rabbit radius.

The object of this experimental work was to evaluate the effect of a noninvasive method of electrical stimulation on the healing of freshly-created osteotomies of the rabbit radius. The apparatus consisted of a solid core electromagnet energized by a square wave unidirectional current. The magnetic field was pulsed transversely across the osteotomy site of the radius while the animal was confined to a restraining device 6 hours daily for 5 days per week. In one group of animals the influence of different pulse frequencies, using 0.1 Hz, 1 Hz, and 4 Hz, was evaluated, while the period of stimulation was kept constant at 2 weeks. In another group of animals, exposure was continued for 3 and 4 weeks while the pulse frequency was kept constant at 1 Hz. Histologic and radiologic comparison with control animals revealed that the initiation of the healing process can be accelerated in magnetic fields pulsed at 1 Hz, but that this effect is not maintained, and that the total period of time required for union is not significantly shortened. In view of these findings, this form of treatment is not recommended for clinical use in the treatment of recent fractures of long bones.

Animals

Electromagnetic interference in implantable pacemakers.

The inhibited pacemaker (VVI or AAI) has become the most popular in recent years because of its ability to combine a physiological advantage with economical current consumption in cases with spontaneous activity. One of its disadvantages is its sensitivity to external electromagnetic interference. Though today's pacemakers possess effective protection against most interference signals there may be instances in which patients are subjected to uncomfortable or even life-threatening situations. This is the case of "amplitude modulated" or "pulsed" fields with modulation frequencies in the physiological range. Fields of that sort have been found in the vicinity of a welder, an electric steel plant, and in medical practice where therapeutic currents were applied. Even touch-actuated switches may influence a demand pacemaker. However, these situations may be overcome by a device within the pacemaker for simple time analysis which can be carried out with few components. If electromagnetic fields of diathermy equipment are applied, today's pacemakers may react with intolerably high or low rates. They should, therefore, be avoided.

Electromagnetic Phenomena

Biological effects of magnetic fields: studies with microorganisms.

Five bacteria and one yeast were grown in magnetic fields of 50-900 gauss with frequencies of 0-0.3 HZ and square, triangular, or sine waveform. Growth of these microorganisms could be stimulated or inhibited depending upon the field strength and frequency of the pulsed magnetic field. Spore germination and mutation frequency were unaffected by the magnetic fields used in this study.

Bacillus subtilis

Effect of electromagnetic pulse on avoidance behavior and electroencephalogram of a rhesus monkey.

A 12-kg male rhesus monkey was exposed to electromagnetic pulse (EMP) at 266 kv/m, 5 pulses/s, for 1 h (18,700 pulses). The effects of EMP on Sidman avoidance behavior and on post-exposure electroencephalogram were evaluated, and no significant changes were detected. An analysis of an EMP showed that it contained various frequency components extending from 0 Hz to 10(9) Hz. However, the pulse configuration was such that its power was mainly confined to the longer wave-lengths (less than 30 MHz). The lack of biologic effect was attributed to the fact that the wavelengths were long relative to the size of the monkey, and little energy deposition was likely to occur. In addition, the electric field was evenly distributed across all lower frequencies so that only a very small electric field component existed at any specific low frequency.

Animals

Slow and rapid responses to CW and pulsed microwave radiation by individual Aplysia pacemakers.

Specific absorption rates (SARs) of microwave energy that altered firing rates were determined for individual pacemaker neurons in the abdominal ganglion of Aplysia californica. A stripline apparatus provided both for artifact-free recording of transmembrane potentials and for precise determination of the rate of absorption of microwave energy. Exposure for two to three minutes at an SAR of only a few mW/g was capable of changing the firing rate of some pacemakers. Two types of responses were observed. The response that was seen in all neurons developed slowly, reaching a steady state in one to three minutes. The other response was seen in a few neurons and occurred within five seconds from the onset of irradiation. Similar responses were obtained for two microwave frequencies, 1.5 and 2.45 GHz. Pulsed radiation induced rapid changes of firing rate more readily than did CW radiation at the same SAR. A convective heating scheme was used to study the effects of temperature changes on the pacemakers' firing rates. Since all of the responses are not readily explained by general heating of the preparation, alternate mechanisms are suggested for the observed effects.

Action Potentials

Lack of microbial genetic response to 2.45-GHz CW and 8.5- to 9.6-GHz pulsed microwaves.

Strain D4 of the yeast Saccharomyces cerevisiae, and strains TA-1535, TA-100 and TA-98 of the bacterium Salmonella typhimurium, were exposed to 2.45-GHz continuous wave or 8.5- to 9.6-GHz pulsed electromagnetic radiation (EMR) at various power densities from 1 to 45 mW/cm2. The temperature during radiation was maintained at 30 degrees C for yeast cultures and at 37 degrees C for bacterial cultures. The studies revealed no increase in mutations or of mitotic gene conversions when cells were radiated for two hours or less. Decreased viability of cells was noted in all cultures tested after radiation at power densities of 30 mW/cm2 or more; however, no reliable changes in genetic events occurred.

Electromagnetic Fields