The question is, does magnet therapy work? And if so, what kind of problems is it best suited for? Magnet therapy essentially comes in two forms: static magnets and electromagnetic fields. Here’s a rundown of each type. But first, read up on magnet therapy products, uses, and cautions.
Magnetic Therapy Products
Magnetic therapy devices typically involve static magnets sewn into some type of cover. Blankets to treat the body or back are available, or you’ll see wraps for the knees, hocks, lower legs, fetlocks, or pastern area.
Magnets for use on the hoof sole are also available; some products have flexible magnetic strips with self-adhesive material on the back that can be placed anywhere on the leg and held in position with a wrap. Pulsed electromagnetic field (PEMF) devices are available as blankets, leg/joint wraps, and even as mats, which the horse stands on for hoof treatments. Because the coils and batteries are bulky and heavy, horses can’t be left loose or unsupervised. The equipment easily slips out of position with too much patient movement.
Some devices are powered by a separate control unit that runs the electromagnetic coils and connects to the blanket or wraps by cables.
While static magnets are left in place for prolonged periods of time, a treatment session with an electromagnetic device would typically be 30 to 60 minutes. Once a day is the usual recommendation, but more frequent applications can also be done.
Static magnet devices cost anywhere from under $100 to $200. PEMF devices are considerably more expensive than static magnet wraps. You can buy an assortment of small devices in the $150 to $200-plus range that only cover a small area. These are highly impractical, since the minimum length of an electromagnetic session would be 30 minutes and you’d have to physically hold it in place all that time. It’s also questionable if these small units generate a powerful enough field to penetrate well.
Magnet Therapy Uses
Whether you should consider trying magnet therapy for your horse depends on what your expectations are. If you’re hoping to heal an injury or reduce healing time, there’s nothing to support that use of the therapy.
Improving blood flow or oxygen in the blood is also likely a false claim.
If you’d like to try to control inflammation and swelling in an acute injury, there’s some scientific evidence to support that possibility, but you’ll find that most manufacturers don’t recommend magnet use on fresh injuries.
The odds of a magnetic device on the sole helping a horse with sole pain are extremely slim, with the possible exception of a horse that has had too much sole pared away and is too close to sensitive tissue. There’s simply too much dead tissue buildup on the foot’s surface for a magnet to even penetrate.
If you’re trying to keep your arthritic horse comfortable and active, the best you can expect is a reduction in pain during warm-up. However, after the magnets have been off for a short time, the pain does return.
If your horse has had a flare up of a problem and is being rested, magnet therapy might be a nice additional pain relieving measure until the area can be brought under control again.
Magnet wraps are most likely to benefit horses with chronic problems that are retired or only used sporadically.
Static Magnet Therapy Cautions
(BUL) Before investing in a magnet wrap, try wrapping the area in which your horse experiences pain with either a neoprene joint wrap or a standing bandage. This alone may provide equivalent relief by limiting movement and increasing warmth.
(BUL) Don’t leave magnetic (or any other) wraps on your horse 24/7. The skin needs to have a period to dry out, and all wraps must be kept clean and dry. A buildup of hair or dirt between skin and magnet could completely block any effect. Some bacteria are attracted to magnetic fields, which can lead to a spread of infection within the tissues if you use them over an infected area.
Static Magnet Therapy Q&A
Q. What is static magnet therapy?
A. Magnets are metals containing iron compounds. What makes them stick and attract certain other metals, like nickel, steel, and cobalt, involves a unique arrangement in how their electrons are positioned around the nucleus.
There’s much more to it than that — and scientists don’t truly understand all the details of what makes certain metals magnetic and what a magnetic field is — but suffice it to say that they have a distinctive arrangement of electrons that makes them interact with certain minerals that have a complementary arrangement. If a magnet meets up with another magnet head on that has a similar magnetic field, their fields will force them apart.
Q. Does static magnet therapy work?
A. Unfortunately, very few studies have been performed on the effects of static magnets on body tissues. We do know that magnets slightly repel water and blood. This is in direct contrast to claims that magnets increase blood flow.
In fact, the few experimental studies that have been done to look at the effects of static magnets on blood vessels have confirmed that magnets are more likely to shrink vessels that are abnormally dilated, or prevent dilation in inflammation, than they are to increase blood flow. But, if magnets can prevent excessive dilation of small blood vessels, this would help control edema/swelling in inflamed areas.
Some static magnetic product manufacturers claim their products increase the amount of oxygen circulating in the blood, often by increments as large as 200 percent! It’s unclear what this claim means. Oxygen is carried throughout the body by being bound to hemoglobin in the red blood cells. Red blood cells have an upper limit on how much hemoglobin they can hold, and there’s no way a surface magnet would influence hemoglobin production.
To increase oxygen concentration in the blood by 200 percent, you’d need to have twice as many red blood cells, which would clog small vessels, or the red cells themselves would have to be holding twice as much oxygen by not delivering it to the tissues — an equally bad situation.
This particular claim has never been proven by any measurement of blood oxygen levels, despite that being a fairly easy test to perform.
Encouraging healing is another common claim, and this one has nothing to support it. In fact, a strong therapeutic magnet won’t reach any deeper than skin level. Experiments have been done where magnets were implanted inside the body at a surgical site, or used on surface incisions, and they conclusively show there’s no improved healing.
Pain relief is a difficult claim to prove or refute, because pain is so hard to actually measure. Some human studies have found a beneficial effect; some found no effect.
Q. What are the results in horses?
A. Although claims of increased oxygen in a horse’s blood are unproven, and blood flow claims may well be the exact opposite, there’s some evidence at least that magnet therapy might help control edema. And the pain relief effect that many people swear they get with magnets is worth considering for your horse.
In my experience, magnet therapy is helpful in about 50 to 60 percent of horses with joint pain, such as low ringbone or other types of arthritis. However, the effect is really only present when the magnet is in place. Some horses respond just as well to having their problem area wrapped with a neoprene or standing leg wrap. However, some horses are obviously more comfortable when their magnetic wraps are in place.
Electromagnetic Field Therapy Q&A
Q. What is electromagnetic field therapy?
A. Static magnets have a natural, but fairly weak, magnetic field. Magnetic fields can also be generated by passing an electrical current through a wire. These fields are typically much stronger and penetrate deeply into the tissues.
When used for veterinary purposes, coils wrapped with wire are incorporated into a mesh blanket or leg wraps/boots and a current is run through them by a battery attached to the blanket or leg device.
The electromagnetic field produced is strong enough to be detected if you hold a magnet in your hand and move it close to the coil. At about three inches from the coil, the magnet will start to vibrate. The electromagnetic field is produced in “pulses,” meaning it shuts on and off multiple times during a treatment.
On units that have adjustable frequencies, low is used to control inflammation, medium frequencies for inflammation and pain, high frequencies for chronic problems where pain is the major issue.
Q. Does electromagnetic field therapy work?
A. While details on exactly how electromagnetic fields work are still pretty sketchy, and there’s still much more study to be done, studies have shown they: (1) improve fracture healing time; (2) stimulate healing in fractures that are not healing well (nonunion or malunion); (3) improve the strength of tendons during healing; (4) relieve arthritis pain; (5) control pain from irritated nerves (such as carpal tunnel syndrome); and (6) control postoperative pain.
Pulsed electromagnetic fields (PEMF) stimulate fibroblasts in tendons/ligaments and chondrocytes in joint cartilage to divide. These are the cells that maintain and repair tendon or ligament tissue and keep joint cartilage healthy. Osteoblasts are the cells that lay down bone. PEMF therapy stimulates that process in cultured bone cells.
There are also studies showing improved healing of chronic wounds, and control of postoperative pain and edema. Some PEMF devices have FDA approval for that specific use. However, there are no requirements for FDA approval for “devices,” as long as they don’t make obvious drug/medical claims.
Eleanor M. Kellon, VMD, of Equine Nutritional Solutions in Ephrata, Pennsylvania, is an authority in equine nutrition and expert in the field of equine nutraceuticals. Her most recent book isHorse Journal Guide to Equine Supplements and Nutraceuticals (Globe Pequot Press).