TENS or Transcutaneous Electrical Nerve Stimulation is the most commonly used pain management modality, which provides short-term pain relief. It is not uncommon for electrical nerve stimulation and electrothermal therapy to be used for relieving the back pain. Intradiscal electrothermal therapy (IDET) is another treatment option designed specifically for the patients with intervertebral disc problems and resulting back pain.
TENS for Back Pain
In TENS treatment for back pain, a miniature, battery-operated device applies low-voltage electrical current through the skin via electrodes placed specifically near the source of pain. The low-voltage electricity from the TENS device interrupts the “pain signals” from the affected area to the brain and sends signals that “scramble” normal pain perception. TENS is not painful and may be effective therapy to mask pain such as diabetic neuropathy. However, TENS for chronic low back pain is not effective and cannot be recommended, the American Academy of Neurology (AAN) now says.
Transcutaneous Electrical Nerve Stimulation (T.E.N.S.) is a back pain treatment that utilizes small voltage electric current for relieving pain. TENS unit is a small battery-operated device. The machine can be hooked on to a belt and is connected to two electrodes. The electrodes carry an electric current from the TENS machine to the skin. Many pharmacies and medical supply stores, though, sell products called ‘TENS belts’ or ‘TENS support belts’. These products claim to use TENS principals to temporarily relieve low back pain related to sore and aching muscles. The belts are said to stimulate muscles or stimulate nerves in the lower back by way of adhesive pads.
‘PAIN GATING’ or How TENS Might Be Helping the Back Pain
There is little research to support how – or even if – TENS really works. Transcutaneous Electrical Nerve Stimulation and the gate control theory of pain use dates back to the 1960s. According to the theory, stimulating nerves closes a “gate” mechanism in the spinal cord, thereby stopping the ‘perception of pain’ signal from the injured site of the body from reaching the brain. During a TENS treatment for back pain, electrodes are placed on the skin over an area of pain in the back. This creates electrical impulses that travel along nerve fibers and create a tingling sensation.
Some people feel reduction in painful symptoms when the TENS is delivered. This could be because stimulating the nerves blocks other pain signals. Another theory is that stimulating the nerves with low voltage electric current encourages the body’s natural painkillers’ (endorphins and enkephalins) secretion.
However, research, generally does not support the use of TENS alone in treating back pain. The review of four randomized controlled studies comparing TENS to placebo, conflicting evidence made it difficult to determine whether TENS has any effect on lowering the back pain intensity. At the same time, in two of the trials, it became evident that TENS did not improve the level of disability due to back pain. There was also some evidence that TENS did not have any role in reducing the number of work days missed due to back pain.
TENS – Using It Safely
TENS, when properly used, is generally safe. If you are considering giving TENS a try in treating your back pain, then the first step is consulting your doctor. The procedure works differently for different people, and it’s not for everyone. Having a pacemaker or either high or low blood pressure that is not controlled, may be a contraindication for using TENS. Before starting TENS, have your health care provider show you how to use it properly. Follow directions carefully and take these precautions:
- Use TENS only for the reason your doctor orders it. Inform your doctor about any changes in your condition.
- Do not leave electrodes attached to the skin for too long without checking and cleaning the skin beneath them.
- If a rash or burn develops beneath the electrodes and is still there after six hours, stop TENS. Also inform your doctor or physical therapist.
- Do not place electrodes on broken or irritated skin.
- Driving is not allowed while using a TENS unit.
- Do not use the device in the shower or bathtub – water and electrical devices do not ‘work’ together.
- Do not use a TENS unit in conjunction with heating pads or cold packs.
- Do not use TENS while asleep.
Discogenic Back Pain and Intradiscal Electrothermal Therapy (IDET)
(IVDs) or intervertebral discs act as shock-absorbing cushions between the vertebrae. Wear and tear and excessive mechanical stresses (like in heavy or repetitive lifting) eventually damage the IVDs and may cause pain. IDET uses heat to desensitize the nerve fibers of an IVD and destroy pain receptors in the area. During the treatment, a wire called an electrothermal catheter is inserted into the disc through an incision. An electrical current is then passed through the wire, heating a small outer portion of the disc to a 90 degrees Celsius.
IDET is an outpatient procedure where the patient is under a local anaesthetic and awake. Preliminary studies have shown that some patients have experienced a continuous relief from pain for up to six months or longer.
The long-term effects of this procedure on the disc have not been determined.
Discogenic Back Pain and Radiofrequency Discal Nucleoplasty
Radiofrequency discal nucleoplasty is a newer procedure that uses a radio frequency probe instead of heating wire to destroy a small portion of the central disc material resulting in partial decompression of the disc, which may help relieve the pressure of the discs bulge pressing on nearby spinal nerve roots and associated pain.