By Kara Amstutz, DVM, CCRT, CVPP, CVA
Resident, American College of Veterinary Sports Medicine & Rehabilitation
Osteoarthritis is a progressive, debilitating condition estimated to affect approximately 20% of dogs ≥ 1 year of age and 90% of dogs > 5 years of age. Veterinary pain specialists and rehabilitation therapists are always on the lookout for additional ways to help their patients live a life without pain.
We understand that there is a definite place for medications, supplements, therapeutic exercise, and even surgery to help a pet feel and function better in their daily activities. However, some patients cannot tolerate medications such as nonsteroidal anti-inflammatories (NSAIDs) due to sensitive gastrointestinal tracts, liver disease, or kidney problems. Additionally, surgery may be too risky or out of financial reach for some pet owners.
There is an “old is new again” technology that has caught the eye of veterinary pain specialists over the last 30 years and is gaining a comeback. PEMF, or Pulsed Electromagnetic Field Therapy, is a modality that was first described in the 1930s but lost favor by the mainstream medical community due to poor study techniques and false advertising. But, over the years, more and more well-designed research studies have found this technology can help humans and pets in a variety of ways with no side effects.
What is PEMF?
PEMF technology is applying a pulsed electromagnetic field (or waveform) to bodily tissues to induce a biological effect. This waveform can come in a variety of frequencies, duration, and amplitude, dependent on the product used to emit the energy. Some products have been found to have very specific biologic effects, while others have fallen short.
The PEMF waveform is designed to penetrate all tissue types, including bone, but it does not produce heat or have negative effects. In fact, since the 1990s, over 3,000,000 treatments have been performed and no side effects have been reported in scientific literature.
How does it work?
Originally, it was discovered that PEMF improved bone healing in cases where complex bone fractures had a delayed union or failure to heal. PEMF units were implanted over the bones and the patients were treated for many hours every day. The bones healed at a faster rate and became stronger with PEMF. The waveforms were found to stimulate bone development by turning on the cells that make new bone.
The prevailing theory has been that when you have a diseased or damaged cell, the charge of the cell becomes low which slows down or halts its normal function. By exposing cells to a magnetic field, the cell can be “recharged” to optimize their role and allow for healing.
More recently, it has been observed that PEMF can have a variety of biological effects including:
- Increasing intracellular calcium release, which signals a host of pathways in the body to regulate metabolism, inflammation, apoptosis, and vascular tone.
- Augmenting production of Nitric Oxide, which is a gas molecule that has cardiovascular effect (vasodilation) but can also have influence on the immune and nervous systems.
- Upregulating heat shock proteins, which have been found to have a cytoprotective effect on damaged tissues.
- Improving Adenosine receptor expression, which then reduces the production of inflammatory cytokines.13
These biological effects can then be used to treat a diverse list of medical issues. The FDA has approved PEMFs use in humans for
- bone healing
- urinary incontinence
- muscle stimulation
- cervical fusion patients at risk for non-union
- depression and anxiety
- and brain cancer.
The National Aeronautics and Space Administration, or NASA, has performed extensive research using this technology to maintain the health of astronauts while on their space missions.
Recent studies have shown PEMF to be helpful in wound healing, such as diabetic ulcers in humans, and incisional healing in pets. A study was performed on dogs undergoing surgery for spinal compression secondary to a degenerative disc where the patients that had PEMF postoperatively had reduced pain of the incision, reduced inflammatory biomarkers, and improved proprioception, which is a common test veterinarians use to assess improvement in neurologic function.
Because osteoarthritis is so widespread, there have been studies looking at how PEMF can help these patients as well. Two studies have found PEMF reduces pain in dogs with knee osteoarthritis, and even outperforms NSAIDs in long-term effects.
In fact, a study performed in guinea pigs found that PEMF can aid in slowing progression of osteoarthritis by protecting the cartilage inside the knee joint. Slowing the progression of osteoarthritis is the primary goal of veterinary pain specialists.
The latest research is investigating PEMF’s ability to treat behavior and cognitive conditions. As mentioned previously, the waveforms can penetrate bone, including the skull, and have a biological effect on the brain tissue. In humans, researchers are looking at using PEMF to treat traumatic brain injuries, stroke, and Alzheimer’s. In dogs, a recent pilot study revealed improved behavior within a month of therapy for separation anxiety. Additional studies are currently being performed in this area.
Which is the best device to use?
There are a plethora of human and veterinary devices on the market which makes it confusing to pet owners as to which may be the best device. The specifications of the device are important to know as we want to make sure the waveforms are causing the desired biological effects. The intensity of the waveform is vital as it dictates how much effect it can have. In human medicine, it is suggested that lower intensity waveforms be used for health maintenance, where a higher intensity is needed for healing, especially in chronic conditions.
There are two main types of devices available for veterinary use, targeted and non-targeted. The waveform parameters are what differentiates the two. The targeted devices, such as Assisi Loops, are designed to treat specific areas of the body, for short durations (such as for 15 minutes twice daily), while the non-targeted devices, such as Respond Systems Pet Mats, are designed to provide whole-body treatments over a longer period of time.
The Assisi loops have a finite number of uses (usually 150-200 uses), while the mats can last up to 6000 uses. The cost of the mats are higher than the loops as well. Therefore, it really depends on what you are treating as to which may be the best device for your pet. If your pet has an acute injury that should heal relatively quickly, the loop may be your preferred choice. However, if your pet has multi-joint osteoarthritis and will need lifelong therapy, the mat would likely be the best method.
Advanced veterinary pain specialists and rehabilitation therapists use a multi-modal approach, which means we attack a problem from many angles. The goal of this technique is to provide better long-term outcomes with a lower risk of side effects. Rather than hit the problem with a big hammer, such as a single drug that may cause a variety of side effects, we chisel away at the issue using multiple techniques to block pain and improve healing. This allows for lower dosing of medication, thus, less risk of negative effects. Overall, this is an exciting addition to the arsenal we have in treating pain, wound healing, and other health issues for our canine companions.
Products
https://assisianimalhealth.com/assisi-loop/
https://respondsystems.com/pemf/canine-products/
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