IFC therapy is a form of electrotherapy that may be a good option for your patients looking to reduce inflammation but without painful side effects.
You already no doubt aware of forms of electrotherapy in your practice to help relieve musculoskeletal pain, inflammation, and stiffness, often with reasonably good results. The most common form is transcutaneous electrical nerve stimulation (TENS). However, you may not always be able to reach a properly therapeutic current level with a TENS machine due to unpleasant side effects for certain patients, particularly those with a low pain threshold.
On the one hand, you could end up having to deliver less than optimal therapeutic levels over more visits. On the other hand, if you reach proper therapeutic levels, despite it being painful for your patients, they may decide it is not worth it to continue with treatment. Unfortunately, either of these scenarios can be frustrating both for you and your patients, and runs the risk of patients opting out of further treatment.
Fortunately, there has been some interesting research on the use of interferential current (IFC) therapy, which appears to provide evidence for having all the benefits of TENS therapy, while not having the side effect of being painful for those patients who are particularly sensitive.
What is IFC? How does it work? Is it beneficial? And how can you use it in your practice?
What is IFC and how does it work?
The basic principle behind IFC therapy works very similarly to TENS. Electrical stimulation pulses stimulate the nerves in the damaged or affected area of the body in order to both block pain and promote healing. The main difference between IFC and TENS is in the use of a medium-frequency current (4,000 Hz) amplitude modulated a low frequency of 0-250 pulses per second (pps).2
In comparison, TENS may often use lower frequency currents, which meet greater resistance when passing through the skin as a barrier. This skin impedance can be painful for particularly sensitive patients. Proponents for IFC therapy claim that the higher frequency currents that IFC uses meet less skin resistance, thereby causing less pain for the patient.1-3
What does the research say?
A 2003 study in the journal Physical Therapy compared the effectiveness of IFC therapy and TENS to sham electrotherapy in a group of otherwise healthy subjects who agreed to undergo induced ischemic pain.3 A group of 30 volunteers were randomized into one of three groups (IFC, TENS, or sham) and reported on any change in pain level following one of the three treatments.
Although there was no difference between IFC and TENS in terms of pain reduction, there was a difference between IFC and the sham electrotherapy, which seems to indicate that IFC can provide benefit in terms of pain relief.
A 2010 article in the same journal performed a meta-analysis to look for patterns among the findings of 14 smaller studies on the possible benefits of IFC.2 Overall, the researchers found that IFC may be beneficial as supplemental therapy along with other interventions to help control pain and inflammation. IFC was also found to be more beneficial than placebo, in line with the 2003 study.
Incorporating IFC therapy into your practice
First and foremost, you do not necessarily need to replace your TENS equipment with IFC. Research has shown that each is effective for different types of pain. For example, IFC has been shown to be more useful for short-term treatment of acute inflammatory pain.1
Conversely, TENS may be a better option for your patients with chronic pain. As mentioned previously, IFC may also be a good option for those patients with low pain thresholds who are likely to find TENS to be painful.
Electrotherapy is an excellent means to provide pain relief beyond just adjustments. By adding IFC to your already existing TENS therapy, you may be able to not only be more effective in your treatments, but also be able to treat patients for whom TENS may not work due to unpleasant side effects.
- Jorge S, Parada CA, Ferreira SH, Tambeli, CH. 2006. Interferential therapy produces antinociception during application in various models of inflammatory pain. Physical Therapy, 86(6), 800-808.
- Fuentes JP, Armijo Olivo S, Magee DJ, Gross DP. 2010. Effectiveness of interferential current therapy in the management of musculoskeletal pain: A systematic review and meta-analysis. Physical Therapy, 90(9), 1219-1238.
- Johnson MI, Tabasam2003. An investigation into the analgesic effects of interferential currents and transcutaneous electrical nerve stimulation on experimentally induced ischemic pain in otherwise pain-free volunteers. Physical Therapy, 83(3), 208-223.