- Jul 1, 1997
Horses are electrically charged. So are people. Sound a bit bizarre? Because of this electrical presence, the use of magnets has been a part of the therapeutical approach to treatment of injuries and other maladies since the 18th century.
All of the cells in a horse--the same is true for humans--have a natural, resting electric current flowing through them. This is known as resting electrical potential, and it is regulated and maintained by the membrane of each cell. This electrical potential is not something that just happens to be present for no good reason. It is necessary for normal cell function and metabolism. Without it, a cell ceases to function and is dead.
Blood is an electrical conductor, and electrolytes are compounds that can carry electric current within the body via the movement of ions such as sodium, potassium, calcium, and magnesium. When these ions with their positive and negative charges pass by a magnetic field, a separation of ions occurs. More later about what the separation of ions means in the way of healing.
The electrical potential of a cell is measured in millivolts (MV). Normal for most resting cells is 90 millivolts of potential. When a cell suffers traumatic injury, the potential might increase to about 120 MV. On the other hand, a cell with a long-standing injury might have only a potential of 30 MV.
This is where magnetic therapy comes in.
Magnetic therapy is said to have a positive effect on the ion exchange and regulation, thus working to get the cell back to its potential with a normal number of millivolts.
Magnetic therapy is not new. It has been around for about 2,000 years. Some scholars believe that the term "magnet" was derived from Magnes, a Turkish shepherd who discovered iron deposits that were attracted to the nails in his sandals. These deposits, now called magnetite (a form of iron), were known to the ancients as lodestones.
In medieval times, lodestones were thought to have strong aphrodisiac powers. They also were touted as being cures for such afflictions as gout, arthritis, and baldness.
By the middle of the 18th Century, durable high-power magnets were available throughout Europe. By the late 1800s, magnets were popular in America. Beginning in the 1960s, research was being conducted on the biologic effects of magnetic fields.
Types of Magnetic Therapies
There are two forms of magnetic therapy. One is administered with the static or permanent magnet, and the other is administered with an electromagnet.
Most of us are familiar with the standard permanent magnet, perhaps having been introduced at an early age to a horseshoe-shaped device that could pick up paper clips and other metallic objects. This type of magnet is used for many functions--everything from keeping refrigerator doors shut to posting notes on them. The magnetic field in a static magnet is always there--permanent.
Electromagnetic or pulsated therapy is provided by padded magnetic coils attached to a battery or plugged into an electrical outlet.
Both forms of therapy, argue proponents, are beneficial, although there is disagreement as to which is better.
Says Ted J. Zablotsky, MD, of Connecticut (who has left the practice of medicine to concentrate on magnetic therapy research and development) magnets, among other things, cause an increase in blood flow. And, as has been frequently documented, an increase in blood flow normally enhances the healing process.
Zablotsky, in a published interview, explained the basics of magnetic therapy and what led him to turn it into a new career:
"The principle of physics that all this is based upon is called the Hall Effect, which says that if I have a moving electrical current, and I put a magnet at right angles with respect to that current, then the particles in that current are going to react in a certain predictable way.
"The blood is chock-full of electrically charged particles. The reactions to the magnet cause the blood vessel to widen and more blood comes to the area. It's not a miracle.
"The reason we got into this is that my sister-in-law was in a car accident...She went through everything modern medicine had to offer and was basically left crippled, using a walker, with heavy-duty doses of anti-inflammatories, muscle relaxers, and pain killers. A friend of my father's from Germany came to visit, and he had about half a dozen of these new magnets with him. She tried them, and she started getting better. My brother said, 'What do you think of these?' I said what any good American doctor would say: 'It's nonsense. It's all in her head.'
"But, he got more of the magnets, and she continued to improve, to the point where she wasn't using the walker any more. So, I did a computer search of the medical literature. I didn't expect to find much. I got back a single-spaced stack of paper 1 1/2 inches thick telling me that everyone in the world knows about magnetic therapy except us here in the states. All around the world they're using magnets."
His sister-in-law, he said, had such a complete recovery from her injuries that she was able to teach aerobic dancing.
Static or permanent magnets, says Zablotsky, have three specific actions on blood vessels. First, there is a slight liberation of heat as the ions separate. Second, the ions crisscross back and forth between the North and South poles of the magnet. Third, small eddy currents occur in the bloodstream, just as the eddy currents in a river push the banks outward.
These effects, collectively, he says, contribute to widening of the blood vessels, which allows more blood to pass through.
At the same time, thermal energy is being produced. This contributes to an increase in regional blood flow, oxygenation, and supply of nutrients.
In addition, there is a cutback in the production of toxic metabolic byproducts, and the increased blood flow aids in the removal of these byproducts.
Zablotsky, in a paper titled "The Application of Permanent Magnets in Musculoskeletal Injuries," gave this description of what happens to tissue when an injury occurs and the role increased blood flow and heat can play in helping heal the injury:
"In an acute injury, the inflammatory reaction attempts to control the effects of the process or agents that caused the injury.
"Immediately upon the occurrence of an injury, two series of events begin--hemodynamic changes and cellular changes. In addition, a chain of chemical mediators is responsible for initiating and regulating the inflammatory process. It is these mediators that are thought to be responsible for the chronic pain syndromes so commonly seen.
"The first reaction to the injury is rapid vasoconstriction of the arterioles, mediated by norepinephrine, which lasts only a few seconds. This is followed by vasodilation, which causes an increase in the amount of blood in the capillary and a rise in mean intercapillary pressure. This increased pressure, in conjunction with the effects of other mediators--histamine, bradykinin, and prostaglandins--on the capillary walls results in extravasation (to force out or cause to escape from a proper vessel or channel) of fluid into the interstitial tissue. At this stage, the capillary walls are only slightly more permeable than normal and the fluid leaking into the tissue is mainly water and electrolytes, rather than protein or cells. These changes in pressure and capillary wall permeability combine to produce edema.
"Depending upon the severity of the inflammation, as well as its duration, various scavenger cells, such as neutrophils, lymphocytes, and monocytes, attack the bacteria or other types of debris present at the injury site. This waste removal actually represents the start of repair, which can last several weeks--again depending on the severity of the injury."
Heat, says Zablotsky, can assist in the healing process, as well as help to eliminate pain.
"Heat can modulate pain through two methods, vascular changes and neurological changes. The neurological control of pain is rooted in the 'gate control theory'--pain signals can be blocked before they reach the substantia gelatinosa if the sensory afferent neurons are sufficiently stimulated. The application of heat, or other stimulation, to an injured part might sufficiently overload the pain transmission with a preponderance of sensory input from thermoreceptors.
"It has also been noted that vascular changes reduce pain by accelerating the natural heating process. Heat applied to tissues increases the metabolism, which causes a relaxation of the capillary system--vasodilation. There is also an increase in flow due to the blood which moves in to cool the heated area. As the flow of blood increases, the concentration of nutrients in the area increases and the potentially toxic waste products in the injured tissue are removed at an accelerated rate. The mediators responsible for propagation of the pain-spasm-pain cycle are also those elements which are flushed from the area by this increased flow, thus effectively interrupting the cycle."
The heating of tissues through the use of electromagnetic devices has been used since the early part of this century, says Zablotsky.
A common problem with these methods has been the inaccuracy in quantifying the actual amount of heat imparted to the tissue, he said.
He is a proponent of permanent magnets, based on a design by German physicist Horst Baerman, M.Sc., to produce heat and increase blood flow.
"Mr. Baerman's design of a series of concentric circles of alternate magnetic poles represents the most efficient pattern conceivable. This pattern ensures that every blood vessel, except for those perpendicular to the skin, will cross a series of North-South poles."
The concentric circle design was critical to magnetic therapy for this reason, says Zablotsky: "Because the magnetic fields acting on the blood vessels are required to be oriented perpendicular to the vessels, the available magnetic pole patterns were inefficient because they failed to recognize variations in human (and equine) physiology. Blood vessels do not travel in straight or predictable paths. One's blood vessels comprise a meshwork, running in several different directions within any given area. The available patterns were either a series of alternate poles arranged on a parallel design, or they were magnetized with one pole covering an entire surface or its opposite surface was oppositely magnetized."
Peggy Fleming, DVM (who also is an acupuncturist), of Odessa, Fla., writing in Veterinary Acupuncture, Ancient Art to Modern Medicine, provides this explanation on the functioning of magnets.
"In every magnet, there is a North pole (South-seeking) and South pole (North-seeking). The South pole, which provides a right-handed spin to electron flow, can be likened to tonification in acupuncture therapy. It increases blood flow and oxygen use, strengthens protein molecules, and increases acidity. The North pole provides a left-handed spin to electron flow. This results in a sedative acupuncture effect. Swelling is reduced, pain is sedated, and protein activity is arrested."
The Language of Magnets
It is time to acquaint ourselves with two terms of measurement when discussing magnets--Hertz and Gauss. The frequency of pulsations when using pulsed electromagnetic devices is measured in Hertz--the number of cycles per second. The strength of a magnet is measured in Gauss.
The magnetic field of the Earth, for ex-ample, is less than 10 Gauss. Static magnets used in human magnetic therapy normally fall between 300 and 500 Gauss. Magnetic resonance imaging (MRI), used in med-
icine to view structures inside the body, introduces a strong magnetic field in excess of 10,000 Gauss.
Both forms of treatment--electromagnets and static or permanent magnets--are non-invasive and pain-free. Static magnetic therapy is administered by applying padded magnetic pads to affected areas. They are often attached with self-adhesive strips or with elastic bandages. These pads can be left on for varying periods of time.
Pulsating magnetic therapy can be controlled by the therapist as to frequency of pulsations (Hertz), the intensity of the pulse (Gauss), and the duration of treatment.
Fleming explains the use of electromagnetic therapy this way:
"Pulsed electromagnetic devices have become very popular in equine sports medicine. These units give the operator the ability to control the polarity of the magnetic field, the frequency of the pulse rate, and the strength of the magnet in Gauss units. Healing is accelerated by simulating normal tissue resonance in both Gauss units and the frequency in Hertz. As in laser therapy, the frequency used depends on the type of injury. In general, low frequency settings are used on acute injury, medium frequencies are used to balance and restore energy, and high frequencies are used on old, cold injuries and scars."
As mentioned, it is theorized that magnetic therapy can relieve pain by stimulating nerve fibers, which, in essence, shut down pain transmission.
Kent M. Thompson, PhD, at the Maxwell Gluck Equine Research Center at the University of Kentucky, conducted research to determine whether magnetic therapy did have an analgesic effect.
Here is his report:
"This study was conducted to determine the therapeutic benefits and mode of action of magnetic therapy in horses. In the initial preliminary experiment, the analgesic capacity of magnetic therapy was investigated.
"This part was conducted with five horses in a repeated measures design experiment. The magnets used for this study were BIOflex magnets, which had been designed with the magnetic fields circularly arranged around the alternate magnetic poles.
"The magnetized magnets and 'placebo magnets' were wrapped around each pastern and fastened in place. Magnets were placed on the limbs approximately 12 hours before the first reflex test was given. To measure analgesic capacity of the magnets, a hoof withdrawal pain reflex test was used. This test elicited a minimal pain response in each horse and the elapsed time from the onset of the pain to hoof withdrawal was measured for both the magnet and placebo treatments.
"The preliminary results of this experiment showed that each limb receiving magnetic therapy had a longer elapsed time before a pain reflex was elicited. This suggests that these magnets provided some analgesia to each treatment site on the forelimbs. The mode of action for magnetic therapy, however, remains to be determined. These results are very promising, and further study is warranted."
Another study involving magnetic pads was carried out under the direction of George W. Pratt Jr., PhD, at the Department of Electrical Engineering, Massachusetts Institute of Technology (MIT).
The overall purpose of the investigation was to determine whether the magnetic pads influenced the circulation of blood. Unlike Thompson's work, which involved live horses, this research was carried out in a laboratory setting without horses.
"Because of the many complicating factors associated with the use of blood itself, such as coagulation, etc.," Pratt reported, "it was decided to work with a very simple system. To that end, a 5% NaCl (sodium chloride) solution (sodium chloride occurs naturally in the blood) in distilled water was selected. The behavior of the saline solution was compared with distilled water itself.
"Fluid was drained from a reservoir through a capillary, which could be exposed to or isolated from the (magnetic) pad. There was no effect on the flow rate of distilled water.
"A statistically significant effect was found on the flow of the saline solution, which was enhanced when the capillary was exposed to the magnetic pad."
Magnetic therapy has been around for a long time, and while there might be debate as to just which form is better, it does appear to be beneficial in treating a variety of injuries.
About the Author
Les Sellnow is a free-lance writer based near Riverton, Wyo. He specializes in articles on equine research, and operates a ranch where he raises horses and livestock. He has authored several fiction and non-fiction books, including Understanding Equine Lameness and Understanding The Young Horse, published by Eclipse Press and available at www.exclusivelyequine.com or by calling 800/582-5604.
POLL: Rehabbing the Injured Horse