TENS (transcutaneous electrical nerve stimulation)
The pain-killing properties of TENS-apparatus are hypothesized to be a result of its effects on pain transmission. There are two theories 1) the gate control theory and 2) stimulus produced analgesia theory.
The gate control theory states that by TENS electrical nerve stimulation stimulates the Aδ-neurons which activate the interneuron and thereby finally prevent the activation of transmission neurons by the pain signals coming from the C-neurons.
The stimulus induced analgesia theory states that less pain is being transmitted due to central endorphins, which are produced from the descending neurons after the TENS electrical nerve stimulation. Both theories, however, do not cover the effects in daily practice and are difficult to prove.
Stimulation of neurons occurs via electrodes placed on the skin. TENS can be effective in control of pain in neuropathy, phantom pain and some cases of back pain.
TENS can be effective in control of pain in neuropathy, phantom pain and some cases of back pain. Except irritation of the skin at the site of the electrodes, TENS does not cause side effects.
One of the contraindications for TENS therapy can be a cardiac pacemaker.