Interferential Therapy

Clinical Application

There are 4 main clinical applications for which IFT appears to be used:

  • Pain relief
  • Muscle stimulation
  • Increased local blood flow
  • Reduction of oedema

In addition, claims are made for its role in stimulating healing and repair and for various specialised applicationphysical threapy 5 – e.g. stress incontinence, though for the former examples (healing and repair) there are more likely to be secondary consequences of these.

As IFT acts primarily on the excitable (nerve) tissues, the strongest effects are likely to be those which are a direct result of such stimulation (i.e. pain relief and muscle stimulation). The other effects are more likely to be secondary consequences of these.

Pain Relief:

Electrical stimulation for pain relief has widespread clinical use, though the direct research evidence for the use of IFT in this role is limited. Logically one could use higher frequencies (90-130Hz) to stimulate the pain gate mechanisms & thereby mask the pain symptoms. Alternatively, stimulation with the lower frequencies (2-5Hz) can be used to activate the opioid mechanisms, again providing a degree of relief. These two different modes of action can be explained physiologically & will have different latent periods & varying duration of effect. It remains possible that the relief of pain may be achieved by stimulation of the reticular formation at frequencies of 10-25Hz or by blocking C fibre transmissions at >50Hz.