Comp Clues


A Non-Drug Approach To Pain Control: Tens and Interferential

By Eric Kirk, (EFL)
| Date: 03/01/2010

What is a TENS or an IF device?
TENS delivers an electrical stimulus through the skin and into the peripheral nervous system. A portable TENS device generates the low-level electrical current; lead wires carry the stimulus to conductive patches (electrodes) placed on the skin and the stimulus is carefully controlled. TENS devices are Class II medical devices that require FDA clearance and a physician’s prescription.

IF devices are similar to TENS, in that, an electrical stimulus is delivered into the peripheral nervous system but the difference lies in the intensity of the currents. IF devices deliver an increased current allowing deeper penetration into the affected areas. These devices are also Class II medical devices that require FDA clearance and a physician’s prescription.

How does a TENS and IF device work?
TENS overrides pain messages that are sent to the brain. To demonstrate this effect think of what happens when you have a burn on a finger and placing the injured finger in cold water relieves the perception of the pain. TENS also induces the nervous system to release endorphins, which are strong neurohormones that help to reduce pain perception.

IF devices increase localized blood flow, which can improve healing by reducing swelling and bringing nutrients necessary for healing to the injured area. The stimulation of local nerve cells can have a pain reducing effect due to blocking pain signals or by stimulating the release of pain reducing endorphins.

What are the indications for TENS and IF devices?

Indications for TENS include the symptomatic relief and management of chronic, intractable pain and as an adjunctive treatment for post surgical and post-trauma acute pain.

Indications for IF include pre and post-orthopedic surgery, joint injury syndrome, cumulative trauma disorders, increase circulation, relax muscle spasms, and pain control of various origins.

When should you use TENS and IF?
TENS and Interferential are effective when:

  • Pain is ineffectively controlled due to diminished effectiveness of medications
  • Pain is ineffectively  controlled with medications due to side effects (cardiovascular or gastrointestinal contraindications and potential addiction and/or tolerance to opiates)
  • History of substance abuse
  • Significant pain from postoperative or acute conditions limits the ability to perform exercise programs/physical therapy

What are the contraindications for TENS and IF?
TENS and IF should not be utilized until the proper diagnosis of pain has been determined. Patients who have pacemakers or defibrillators should consult with their physicians prior to use.

Are TENS and IF devices affordable?
TENS and IF devices are high value alternatives when you weigh the modest acquisition cost verses the overall efficacy when treating for long-term pain management. After the initial expense of the devices, the only additional costs are the electrodes. With the reduction of pain medications or other treatments, the price of the devices can be recouped within the first twelve months.

How long should the patient use their TENS or IF device?
Depending on the nature and severity of the patients’ pain, they may need to use the device minimally or on a constant basis. Over time, the condition of the patient should improve and the usage of the device should decrease. TENS and IF devices are non-addictive and have no known side effects other than possible skin irritation from the electrode, so continued use is not detrimental to the patient

How does a patient receive a TENS or IF device?
The patient can receive a TENS or IF device by visiting their physician or therapy clinic. During this visit, the clinician will properly assess the patient injury and give instruction on the usage of the device.

So why choose an Empi device?
Empi, a DJO company, has been the leading manufacturer and provider of non-invasive medical products for pain management and physical rehabilitation for over 30 years. Empi is committed to delivering positive patient outcomes and providing innovative products specifically designed to meet the needs of the patient and medical professionals.

Empi is a trusted brand amongst clinicians and the product line has been innovative in the discipline of electrotherapy. Some of the characteristics that differentiate Empi from their competitors are:

Lifetime warranty on TENS devices

  • Dedicated sales staff for training patients and clinicians which leads to improved patient compliance
  • Simple Modulated Pulse (SMP) mode, which is a patented waveform that assists in the reduction of pain by fluctuating from high to low frequency over a short duration
  • Active TENS, the most innovative TENS device on the market with one touch activation
  • Select TENS, One touch site specific buttons to launch preset programs for the knee, shoulder, low back/hip, hand/wrist and back also has compliance meter for patient usage
  • IF 3WAVE, an interferential combination providing three distinct modalities in one powerful, portable device – IF, NMES, and PDC.

Physicians write more prescriptions for Empi devices than any other brand. Over one million patients have been treated with Empi devices allowing patients to achieve higher functional levels and ultimately greater satisfaction.

If you would like to learn more about our company or devices, please do not hesitate to visit our website at or phone us at (800) 328 2536.