Pulsed electromagnetic field therapy (PEMFT), also called pulsed magnetic therapy, pulse magnetotherapy, or PEMF, is a reparative technique most commonly used in the field of orthopedics for the treatment of non-union fractures, failed fusions, congenital pseudarthrosis and depression. In the case of bone healing, PEMF uses electrical energy to direct a series of magnetic pulses through injured tissue whereby each magnetic pulse induces a tiny electrical signal that stimulates cellular repair. Many studies have also demonstrated the effectiveness of PEMF in healing soft-tissue wounds; suppressing inflammatory responses at the cell membrane level to alleviate pain, and increasing range of motion. The value of pulsed electromagnetic field therapy has been shown to cover a wide range of conditions, with well documented trials carried out by hospitals, rheumatologists, physiotherapists and neurologists. There are several electrical stimulation therapy devices, approved by the FDA, that are widely available to patients for use. These devices provide an additive solution that aid in bone growth repair and depression.[1][2]
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The use of magnetic field therapy in clinical applications dates back over 500 years. In the 15th century, Swiss physician and alchemist Paracelsus used lodestones, or naturally magnetized pieces of the mineral magnetite, to treat conditions such as epilepsy, diarrhea, and hemorrhage. He believed that the ability of magnets to attract iron could be replicated by attracting disease away from the body. In the late 18th century, the Austrian physician Franz Anton Mesmer, who originated the idea of "animal magnetism", described the healing properties of passing magnets over the open veins of patients.[3] In the mid-19th century, magnetic ointments produced in New York were introduced as remedies for a whole spectrum of illnesses such as headaches, inflammation of the bowels, burns, fever sores, rheumatism, gout, and toothache.
Although electricity’s potential to aid bone healing was reported as early as 1841, it was not until the mid-1950s that scientists seriously studied the subject. Fukada’s and Yasuda’s discovery of the electric potential of bone provides evidence of electricity’s effect in promoting osteogenesis (bone growth), particularly in long bone non-unions.[4] During the 1970s, Bassett and his team introduced a new approach for the treatment of delayed fractures, a technique that employed a very specific biphasic low frequency signal [5][6][7][8] to be applied for non-union/delayed fractures. The use of electrical stimulation in the lumbosacral region was first attempted by Alan Dwyer of Australia. In 1974, he reported successful initiation of graft incorporation in 11 of 12 fusion patients. Since that time, electrical stimulation has been shown to significantly increase the probability of bony arthrodesis in spinal fusions.[9][10]
In 1979 the FDA approved non-invasive devices using pulsed electromagnetic fields designed to stimulate bone growth.[11]
In 2004, pulsed electromagnetic field system was approved by FDA as an adjunct to cervical fusion surgery in patients at high risk for non-fusion.[12]
The use of PEMF stimulation has been found to be safe.[13] It has also been proven safe and effective in treatment of delayed union in long bone fractures and patients at a risk of non-union following spinal fusion surgeries.[14]
In 1974 it was demonstrated that a pulsed magnetic field applied across the site of a bone fracture can accelerate the healing process (BASSETT et al., 1974). The mechanism of osteogenesis is not clear, however the use of PEMF therapy as an adjuvant therapy for delayed- and non-union fractures was supported by empirical evidence collected through clinical studies.[15][16] While PEMF therapy may offer some benefit in the treatment of fractures, the evidence is inconclusive and is insufficient to inform current clinical practice.[17]
PEMF therapy has been suggested to enhance healing of fractures that occur in patients with diseases such as diabetes, vascular insufficiency, and osteoporosis, and those taking medications such as steroids and non-steroidal anti-inflammatory drugs (NSAIDs). The exact mechanism for fracture healing is unclear; however, it is thought that PEMF therapy causes biochemical changes at the cellular level to accelerate bone formation.
There are few clinical trials that have demonstrated PEMF therapy as an effective treatment for tissue trauma, particularly in the early stages of inflammation.[18][19] Electrical stimulation has been shown to significantly increase the probability of bony arthrodesis in spinal fusions. The use of low-energy, time-varying magnetic fields (commonly referred to as pulsed electromagnetic fields or PEMF) has been successful when used adjunctively to fresh fusions and in the case of treating a failed fusion, PEMF bone growth stimulation is a successful method which avoids a revision surgery.[20]
Based on a 2007 clinical trial, Thomas et al. conclude,
PEMF may be a novel, safe and effective therapeutic tool for use in at least certain subsets of patients with chronic, nonmalignant pain.[21]
In 2009, NASA was awarded a US patent – US 7,601,114 B2 – that utilized pulsed electromagnetic fields to enhance tissue repair in mammals. This patent was the result of research carried out by NASA to find methods to reverse the bone loss that is experienced by astronauts when they were in a gravity free environment and away from the earths magnetic field. As an adjunct to the NASA tissue repair patent, pulsed magnetic fields were also used to stimulate the growth of stem cells.
In 2002, Health Canada certified the use of PEMF to treat severe depression and currently several private Canadian clinics offer PEMF therapy. In 2011, the FDA approved the NeuroStar TMS Therapy system for use if the patient failed to respond to antidepressants. This treatment, known as transcranial pulsed electromagnetic therapy uses a strong electromagnetic field that is pulsed into the patients head. The treatment usually consists of two 15 minute treatments each day for two weeks.
The use of PEMF to remedy various diseases and mental illness is not widely known by general medical doctors because it is not promoted as a first line of treatment in medical schools. The general public usually learns about this form of therapy on the internet when looking for alternatives to pharmaceuticals . In Nov. 2011, the use of PEMF was brought to the attention of millions of North America TV viewers who watched the Dr.OZ show that featured several PEMF devices.