Transcutaneous electrical nerve stimulation (TENS, TNS, TENS therapy; transcutaneous electrical nerve stimulation) is an electromedical stimulation current therapy for pain treatment.
Indications (areas of application)
- Herpes zoster neuralgia (synonym: zoster neuralgia; extremely severe nerve pain resulting from shingles).
- Phantom pain
- Neuralgia (nerve pain)
- Lumbago (lumbago)
- Rheumatic diseases
- Degenerative diseases of the skeletal system (wear and tear or overload of the skeletal system).
- Sports injuries
- Pain due to congenital or acquired deformities of the musculoskeletal system.
- Pain in the context of cancer
- Pain in the context of circulatory disorders
Contraindications
- Persons with cardiac pacemakers
- Persons with epilepsy
- Electrodes should not be placed on damaged skin
The procedure
Transcutaneous electrical nerve stimulation involves the generation of electrical impulses in a small device, which are then transmitted to the body to the painful area by means of electrodes.
Four mechanisms are used to explain the analgesic effect (effect that cancels or suppresses the sensation of pain) of transcutaneous electrical nerve stimulation:
- The electrical impulses stimulate pain-inhibiting messenger substances, so-called neurotransmitters (endorphins, encephalins), which are increasingly released. These block the receptors in the nervous system, where otherwise pain-triggering messengers would accumulate.
- Blood flow-promoting vasodilatory substances such as vasoactive intestinal polypeptide (VIP hormone) are also formed increased.
- Pain-inhibiting systems in the spinal cord are activated, thereby blocking the transmission of pain impulses
- Impulse transmission of peripheral nerves (located outside the spinal cord and brain) is blocked by electrical inhibitory processes
In all the above cases, the electrical impulses increase the pain threshold.
The best evidence is a frequency of the pulses of 80 Hz, so the pain threshold can be raised up to 20%.With this method, pain medication can often be saved or reduced and thus decreases the risk of severe side effects.
Important for the correct application are the right electrode size, the appropriate placement of the electrodes and the correct setting of the current frequency. Studies have shown that even placing the electrodes far away from the painful area results in pain relief, but the pain relief is less than the pain relief from electrode placement close to the source of the pain.
Different arrangements of electrodes are indicated depending on where the pain is located.
The duration of a treatment is generally about 30 minutes per session. Since success usually lasts only a few hours, treatment is often given several times a day. In acute diseases, the symptoms usually subside quickly. For chronic diseases, however, home treatment must usually be considered.
The TENS device is easy and safe to use after instruction by the attending physician.
By using the TENS unit, pain can be reduced or even eliminated in many cases without side effects. The TENS unit can be combined well with medications and other pain-fighting measures.
Possible complications
Complications are rare due to the very good tolerability of TENS therapy:
- Current-related skin irritations
- Skin irritations due to incompatibility of the electrode contact gel.
