Transcutaneous electrical nerve stimulation (TENS) is used to numb and relieve pain. TENS works by delivering mild electrical impulse to the targeted area, thus blocking pain signals from getting through to the brain. TENS is safe, easy to use, cost efficient and convenient.
As early as 1700's, physicians have been using electricity on patients to treat different kinds of medical conditions including migraine headaches  . In 1874, Isac Von Hohenheim invented crude form of a TENS machine for his patient who was suffering from Rheumatism  . Since then there has been many advancements in technology which led TENS machines becoming widely available on prescription drugs.
Since 1970s clinical studies started showing positive results of using TENS for pain relief  .
TENS can be used to relieve chronic nerve pain, which is the most common symptom of diabetic neuropathy  . TENS therapy also effective against post surgical neuralgia and radicular arm pain caused by herniated cervical disc. TENS has also been found effective in treating the arm or leg pains caused by peripheral neuropathy.
One out of every three patients with diabetes will develop neuropathy over a period of time and these individuals are at risk for developing other serious health conditions such as heart diseases  . Therefore diabetic people who have been diagnosed with nerve pain need to seek immediate professional help and advice.
Transcutaneous Electrical Nerve Stimulation (TENS) should only be use under professional supervision. Prolonged use of tens without proper supervision can cause some serious medical conditions especially those with heart diseases. The safety concerns will always outweigh any potential benefit you may gain from the therapy.
In a research study conducted by Fannin & Cleary (1991), TENS was found effective in eliminating neuropathic pain. The study included 13 subjects that have leg pain caused by diabetic peripheral neuropathy  and used two different forms of TENS therapy to measure the effectiveness. One form of Tens used a 20 percent constant current with pulse duration set at 1 second. The other type of tens used stimulus rate of 50 pulses per second at an intensity level between 200 to 300 microamperes. It was concluded that both types of TENS using either parameters had similar effectiveness in treating nerve pain but the one using pulse 1 sec with 20% constant has shown more positive results than the other which is stimulating 50 times per second with an intensity level between 200 to 300 microamperes.
According to a research conducted by Singh et al., Transcutaneous Electrical Nerve Stimulation is not effective in reducing neuropathic pain caused by herniated cervical disc, but it may be beneficial to some patients with chronic low back pain  . The study examined the effectiveness of TENS machines and clinical trials over a period of three weeks. Subjects included were people suffering from painful condition due to nerve compression because of degenerative discs which cause their nerves either being impinged or inflamed.
Research conducted by Bors et al., found that Transcutaneous Electrical Nerve Stimulation over a period of three months had shown positive results for treating chronic nerve pain and improving function  . The participants were randomized into two groups, one group received sham therapy and other served as controls who used standard medication. Subjects in the study have been diagnosed with painful diabetic neuropathy, post surgery neuralgia or radicular arm pain caused by herniated cervical disc. It was concluded that both groups receiving either real or placebo treatment showed comparable improvement of symptoms and function.
TENS is found to be effective in reducing chronic neuropathic pain and improving sensation, motor strength, sleep disturbances, activity level on self-report measures, as well as blood glucose levels  . Participants in the study were all patients diagnosed with painful diabetic peripheral neuropathy. It was concluded after using TENS for a period of six weeks that there has been improvement in all the clinical outcomes but could not reach statistical significance probably due to small sample sizes available for each test group.
While TENS may show positive results on eliminating neuropathic pain caused by acute injury or surgery or spinal cord injury, it can also prove useful when treatment is applied before any damage occurs to nerve fibers  . The study looked into the effectiveness of TENS in relieving pain caused by nerve compression because of disc herniation. The findings revealed that using TENS for a period of forty five days reduces symptoms and pain caused by the condition.
TENS may be effective in reducing symptoms for people who have had spinal cord injury  . A recent study has shown that TENS is a safe method of treatment which offers significant pain relief to patients with chronic back pain as well as improving quality of life. Transcutaneous Electrical Nerve Stimulation has been found to help gain better sleep as well as increased function for physical activities after a period of six months. Treatment was also reported to reduce depression and anxiety, while improving self-esteem seen in participants after treatment.
Patients who have undergone spinal cord injury as well as those who have been diagnosed with multiple sclerosis may find Transcutaneous Electrical Nerve Stimulation effective in reducing their pain  . Results from patients' self-report found that there was an improvement on both physical and psychological well being after receiving TENS treatment for a period of one month. Those who received real therapy had more significant improvement than direct control group who receive sham treatment. Patients were asked to complete the outcome measures at various times during study, which were pre-treatment, post-treatment and follow-up. Outcome measures include visual analog scale (VAS), the McGill Pain Questionnaire, the Short Form 36 (SF-36), Beck's Depression Inventory II (BDI-II) and Functional Independence Measure (FIM).
While treatment was found ineffective in treating the neck pain, TENS proved helpful for relieving lower back pain both at rest and during physical activities. It has been explained that when using higher intensity levels (300 microamps) for longer duration, there are less than normal side effects as compared to moderate intensity levels (150 microamps) with shorter treatment duration. TENS still remains to be the first line of defense in eliminating nerve pain caused by purely mechanical condition instead of any medical condition.
TENS therapy has been proven to help reduce pain caused by chronic musculoskeletal conditions especially for those patient who have failed conventional medical treatment  . Recent study shows that Transcutaneous Electrical Nerve Stimulation is an effective modality of treatment when used with a large case mix patients such as the elderly and those who are suffering from osteoarthritis of the knee or hip. A total of forty seven patients were included in the research and divided into two groups; one treated using TENS and control group given sham treatment. It was found that both groups had significant improvement on physical function (+22%) even though differences could not reach statistical significance. participants in the TENS group had improvements on quality of life (QoL) as compared to those in the sham control group (+11%) and did not have any side effects. One of the main complications when using medical treatment for musculoskeletal pain is drug related adverse events, which may lead to chronic pain and even overdose. Transcutaneous Electrical Nerve Stimulation has been reported by previous studies to be cost-effective and safe alternative mode of therapy at home  . Side effects are minimal and usually transient, which make it a preferred treatment for patients with Diabetes mellitus type 1 who have neuropathy diagnosed.
TENS has been found to reduce postherpetic neuralgia  . Postherpetic neuralgia is a condition in which the nerve becomes damaged from either shingles infection or trauma as well as after receiving treatment for cancer. Pain and burning sensation can be so severe that patients have trouble sleeping at night, as well as having problems with concentration during the day time. TENS has been able to reduce pain by 35% when applied 2 hours twice a week. In one of the studies, it was found that participants had significant improvement on their quality of life, they were better able to walk freely (70%) and were able to enjoy physical activities compared with control group who did not receive therapy. When applied over two sets of pads for six months Transcutaneous Electrical Nerve Stimulation was also effective in reducing pain caused by postoperative dental pain. One of the side effects that was reported to be mild for TENS therapy is skin irritation which usually disappeared within a week. The main aim when using treatment for postherpetic neuralgia is to relieve patient's pain, and this can only be achieved by reducing contact with sources of pain such as sensation in affected area, which is why many patients prefer Transcutaneous Electrical Nerve Stimulation over other forms of neuropathy therapies.
TENS has also been found to help reduce symptoms associated with diabetes mellitus type 2  . It had also been noted that TENS was well tolerated by most patients even though longer trials are recommended for better results. About half of participants did not discontinue treatment because they saw some improvement in their symptoms. Most participants had some improvement on sensitivity to pain with TENS therapy, but it was seen as only short term relief from chronic pain associated with diabetes.
TENS has also been used to help patients suffering from chemotherapy induced neuropathy  . It is estimated that more than half of those undergoing cancer treatments suffer from nerve damage, usually for the rest of their lives. Transcutaneous Electrical Nerve Stimulation has been found to be effective in reducing pain and other related symptoms like numbness by up to 34% when applied 2 hours twice a week over a period of four weeks after chemotherapy sessions were completed. This effect lasted up to twelve months after cessation of treatment indicating long term effects especially for this type of chronic pain.
Some patients may experience some side effects from using TENS, but the majority of them are temporary. The most common side effect is skin burn, which can be prevented by applying plastic film before beginning treatment or turning down intensity level. If the patient does not receive any benefit and no improvement in pain after 2 to 3 weeks, he should consult his doctor at once because it might indicate an underlying medical condition.
Transcutaneous Electrical Nerve Stimulation is a well known treatment for chronic pain whether it is caused by Diabetes mellitus type 2, postherpetic neuralgia or even chemotherapy induced neuropathy. It has minimal side effects especially when compared to common medications used in treating neuropathy pain like Lyrica, Gabapentin and morphine which can have serious adverse events especially if taken over long period of time. TENS therapy as an alternative model of therapy for neuropathy should be considered due to its ease of use, cost effectiveness and safe results obtained from previous studies on this mode of treatment . [ARTICLE END]
TENS (Transcutaneous nerve stimulation) does not appear to be effective for diabetic peripheral neuropathy. Further research is required to determine if other uses of TENS are effective (e.g. post herpetic neuralgia).
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