Interferential Therapy

This posting is dedicated to my devoted physiotherapist (Hi Polly) who helps me cope with a sudden shoulder pain. I told her about QTSaver and I'll try to demonstrate what it's worth by collecting info about Interferential Therapy, a term she taught me today, a term I've never heard about before I met her.

It took me half an hour to collect and edit the following:

http://www.healiohealth.com/tek9.asp?pg=products&specific=jnnrmmm8
Interferential current therapy (IFC): This type of stimulation is characterized by the crossing of two electrical medium, independent frequencies that work together to effectively stimulate large impulse fibers. These frequencies interfere with the transmission of pain messages at the spinal cord level.
Interferential current therapy is essentially a deeper form of TENS. In essence, IFC modulates a high frequency (4000 Hz) carrier waveform with the same signal produced by a TENS unit.
Conventional TENS and Neuromuscular stimulators deliver most of the stimulation directly under the electrodes. Thus, with Interferential Stimulators, current perfuses to greater depths and over a larger volume of tissue than other forms of electrical therapy. When current is applied to the skin, capacitive skin resistance decreases as pulse frequency increases.'
Interferential Therapy is used in the treatment of circulatory disorders, range of motion, edema and muscle spasms. Post-op patients will use the device 3 times a day for 15 minutes over a period of 14 - 30 days.
Since Interferential Therapy has been in use for many years, its effectiveness is well documented. Studies have shown that patients using Interferential Therapy after surgery develop fewer post-op complications than those relying solely on narcotics for pain relief. Interferential stimulation does not cause respiratory depression. Interferential Therapy aids in circulation, decreasing the recovery time for patients.
http://www.bcbst.com/MPManual/Interferential_Current_Therapy_(Interferential_Stimulator-IFII).htm
However, because there is minimal skin resistance with the interferential current therapy, a maximum amount of energy goes deeper into the tissue. It also crisscrosses, as opposed to the linear application of the TENS.
This prevents the treated area from adjusting to the current. POLICY Interferential current therapy and the device for the treatment of pain are considered medically necessary if the medical appropriateness criteria are met.
Any device utilized for interferential current therapy must have FDA approval specific to the indication, otherwise its use will be considered investigational. MEDICAL APPROPRIATENESS Any device utilized for this procedure must have FDA approval specific to the indication.
Interferential current therapy is considered medically appropriate for any of the following conditions: Pain is ineffectively controlled due to diminished effectiveness of medications; or Pain is ineffectively controlled with medications due to side effects; or History of substance abuse; or Significant pain from postoperative or acute conditions limits the ability to perform exercise programs/ physical therapy treatment; or Unresponsive to conservative measures (e.g., repositioning, heat/ice, etc.). The FDA has issued the contraindication that powered muscle stimulators should not be used on individuals with cardiac demand pacemakers.
http://www.medi-stim.com/if.htm
Tips for Effective Treatment by Jim LaneInterferential therapy, during the past ten years, has increased in popularity to the point that it is now perhaps the most widely used form of electrotherapy in the United States. First developed in Europe, where this unique form of stimulation has been utilized for numerous indications, interferential units have been marketed since the early 1950's. It seems, however, that a great deal of confusion, mystery and perhaps even misinformation still exists concerning this therapy. The purpose of this article is to shed some light on areas that may be confusing to the clinician, share information on proper treatment protocols and offer a few insights into treating patients with interferential therapy effectively and safely.
The original concept of interferential therapy was developed by Austrian physician, Dr. Hans Nemec, approximately forty years ago.
One output of the unit is a constant 4000Hz while the second output frequency is adjustable from perhaps 4001Hz to as much as 4250Hz. This form of interferential therapy has become known as "true interferential" or "frequency difference interferential".
When treating acute pain with the 80Hz to 120Hz setting, interferential therapy will provide a release of enkephalin with a treatment time of 10 to 12 minutes. Chronic pain, however, requires 15 to 20 minutes of the 3Hz to 15Hz setting to provide release of beta-endorphins.
Interferential therapy provides a comfortable, soothing stimulation and should never be strong enough to cause any discomfort to the patient. Higher intensities should not be considered "better" as far as obtaining results.
It is important to note that once the patients comfort level is established at the onset of therapy, the intensity should not be increased during the treatment. This could cause over stimulation of the tissue and even minor burns, particularly when treating with a unit that produces "true interferential" due to the Widensky inhibition effect.
Interferential therapy is considered a very safe modality when used properly for appropriate conditions. Most manufacturers list similar contraindications and precautions, most of which are the same as other electrotherapy devices.
http://www.electrotherapy.org/electro/interferential/interferential.htm
The basic principle of Interferential Therapy (I/F) is to utilize the strong physiological effects of low frequency (@ 250pps) electrical stimulation of muscle and nerve tissues without the associated painful and somewhat unpleasant side effects of such stimulation. To produce low frequency effects at sufficient intensity at depth, most patients experience considerable discomfort in the superficial tissues (i.e. the skin).
It is not capable of direct stimulation of nerve in the common context of such stimulation. Interferential therapy utilizes two of these medium frequency currents, passed through the tissues simultaneously, where they are set up so that their paths cross & in simple terms they interfere with each other. This interference gives rise to an interference or beat frequency which has the characteristics of low frequency stimulation.
http://www.skylarkdevice.com/web-site/IF.htm
It also prevents muscle weakness and increases range of motion and local blood circulation. SD-730 (STIM) Interferential StimulatorIs used for the symptomatic relief and management of chronic (long-term) intractable pain. Interferential therapy is based on the effect of low-frequency stimulation as in the biological frequency range. IF-727 Interferential StimulatorThis leads to a biologically effective spectrum of 4-400 bps, which penetrates deeply into soft tissues and bones and produces a wide range of physiological effects. IF-400 Interferential StimulatorIs used for symptomatic relief and management of chronic intractable pain and as an adjunctive treatment in the management of post surgical and post traumatic acute pain problems.
http://www.docguide.com/dg.nsf/PrintPrint/D2237BE4835AB99A85256B02004D2E90
November 12, 2001 -- Manipulative therapy and interferential therapy appear equally effective in reducing low back pain, as is a combination of the two therapies. The findings, from a multicentred, randomized, controlled trial, were presented at the 4th Interdisciplinary World Congress on Low Back and Pelvic Pain, in Montreal, Quebec, Canada.
The study allocated patients to one of three groups: manipulative therapy alone, interferential therapy alone, and a combination of the two therapies. Patients included in the study were between 18 and 65 years of age and had non-specific low back pain of between one and three months duration, avoiding patients with chronic pain or those who would recover spontaneously from being enrolled.
Deirdre Hurley, PhD, a physiotherapist at the University of Ulster in Northern Ireland, in Ulster, United Kingdom, and the study's principal investigator. "There are currently no recommendations for the use of interferential therapy in the UK. They advocate manipulation and exercise.