Pain reduction using transcranial electrostimulation: a double blind "active placebo" controlled trial. Immediate influence of transcranial electrostimulation on pain and beta-endorphin blood levels: an active placebo-controlled study. Transcutaneous electrical nerve stimulation vs. transcutaneous spinal electroanalgesia for chronic pain associated with breast cancer treatments. Transcutaneous electrical nerve stimulation in the relief of primary dysmenorrhea. Transcutaneous electrical nerve stimulator for procedural pain associated with intravenous needlesticks. An evaluation of transcutaneous electrical nerve stimulation for pain relief in labour. Temporary pain relief using transcranial electrotherapy stimulation: results of a randomized, double-blind pilot study. Acupuncture and transcutaneous electric nerve stimulation in the treatment of pain associated with chronic pancreatitis. A randomized study. Diabetic peripheral neuropathy: amelioration of pain with transcutaneous electrostimulation. Acupuncture and transcutaneous nerve stimulation in stroke rehabilitation: a randomized, controlled trial. Modification of haemophiliac haemorrhage pain by transcutaneous electrical nerve stimulation. Pain reducing effect of three types of transcutaneous electrical nerve stimulation in patients with chronic pain: a randomized crossover trial. The amelioration of the suffering associated with spinal cord injury with subperception transcranial electrical stimulation.
To examine the efficacy of transcranial electrical stimulation a non-invasive method of reducing pain.
                A randomized, double-blind, placebo-controlled trial.
                A total of 119 patients with chronic pain.
                Patients were treated with either transcranial electrical stimulation or an active placebo device. Short- and long-term follow-ups were evaluated for treatment efficacy with 4 ordinal scale variables: visual analogue scale (pain level), SLEEP (how often does pain disturb sleep), FREQ (frequency of pain) and MED (frequency of use of medications to relieve pain).
                Pain level decreased significantly in the transcranial electrical stimulation-treated group compared with the active-placebo group 3 weeks after the end of treatment (p = 0.0017 between groups). Other parameters did not demonstrate significant differences. Three months after the end of treatment this effect was maintained and other treatment parameters showed similar improvements.
                Transcranial electrical stimulation is an effective non-invasive method for pain relief. The active placebo device has a powerful effect on reported pain, which diminishes in the long-term. The involvement of possible neural mechanisms is discussed. Stimulation of the antinociceptive system by noninvasive electrical current from electrodes placed on the head is a renewed method of pain relief.
                We conducted a randomized, double-blind, placebo-controlled study on 20 chronic back pain patients. They were treated with either transcranial electrostimulation (TCES) or an active placebo device. Pain level and serum beta-endorphin levels were measured before and after treatment.
                beta-Endorphin level increased in seven of the ten patients from the treatment group and did not change in eight of ten patients from control group (P = 0.057 between groups). Pain level decreased in eight treated patients and seven control patients (significant decrease for each group, no significant difference between groups).
                Transcranial electrostimulation is a nonpharmacologic method of pain relief accompanied or mediated by beta-endorphin release. The comparable degree of the initial clinical response emphasizes the powerful placebo effect on reported pain not mediated by endorphin release. This preliminary study shows that noninvasive electrical stimulation is a safe treatment with a positive effect on beta-endorphin blood levels. Chronic pain associated with breast cancer treatment is becoming increasingly recognized. Patients with this condition can experience significant physical and psychological morbidity and may benefit from nonpharmacological interventions as part of a multidisciplinary team approach. We compared the effectiveness of transcutaneous electrical nerve stimulation (TENS), transcutaneous spinal electroanalgesia (TSE), and a placebo (sham TSE) in a randomized controlled trial. The study sample comprised 41 women with chronic pain following breast cancer treatment, and outcome measures included pain report, pain relief, pain interference, anxiety and depression, arm mobility, and analgesic consumption. There was little evidence to suggest that TENS or TSE were more effective than placebo. All three interventions had beneficial effects on both pain report and quality of life, a finding that may be due to either psychophysical improvements resulting from the personal interaction involved in the treatment or a placebo response. Although electrical stimulation appears to be well tolerated in this population, further research is needed to establish its effectiveness for chronic cancer treatment-related pain. The purpose of this study was to replicate a previous study to determine the effectiveness of acupuncture-like transcutaneous electrical nerve stimulation in treating primary dysmenorrhea. Twenty-one women with dysmenorrhea received a placebo pill or 30 minutes of acupuncture-like TENS. All subjects completed two pain questionnaires before treatment; immediately posttreatment; 30, 60, 120, and 180 minutes posttreatment; and the next morning upon awakening. Each woman also participated in a separate study measuring electrical resistance at four auricular acupuncture points before and immediately after treatment. The data were analyzed with a two-factor repeated-measures analysis of variance, which revealed statistical significance over time but not for group or interaction between group and time. Results revealed an average pain relief of at least 50% immediately posttreatment, indicating that acupuncture-like TENS may be useful for dysmenorrheic pain. This study also suggests that auriculotherapy via acupressure may relieve the pain of primary dysmenorrhea. Venipuncture continues to be considered a painful and unpleasant experience for those receiving medical treatment. A prospective study investigating whether the application of a transcutaneous electrical nerve stimulator (TENS) decreases the complaints of pain and unpleasantness with i.v. needle insertion was conducted using a group of 71 subjects who were double-blinded and randomized to one of three groups: TENS, placebo-TENS, and control. This article gives an overview of this research and describes its findings. The effectiveness of transcutaneous nerve stimulation (TENS) for pain relief in labour was evaluated by randomizing 280 patients in early labour into 2 groups. Inoperative sham machines were applied to patients in the control group and active units to those in the test group. Neither patients nor attending labour ward staff were aware of which group the patient was in. The intensity of low back pain and abdominal pain was assessed by the patient each hour on a visual analogue pain scale. Each patient served as her own control by switching off the machine for 2 contractions every hour and then recording the intensity of pain. The amount of conventional analgesia each patient received was recorded by labour ward staff. There was no difference in the intensity of pain recorded by each group. Nor was there any difference between the 2 groups in the change of pain experienced when the machine was switched off. Moreover there was no difference in the amount of other analgesia required. Some differences were found when those with little low back pain were excluded from the study. We conclude that TENS is ineffective as a routine method of pain relief in labour. It is likely to benefit only those with severe back pain and then only to a modest degree. Results of a randomized, double-blind pilot study indicate that transcranial electrotherapy stimulation may be an effective treatment for the temporary reduction of pain in osteoarthritis patients. Presently, the predominant method for pain management is medication. One very different approach is the application of micro- to milliamp current applied to specific areas of the head, resulting in a release of endogenous opioids from pain management regions of the brain. For the pilot study, 64 subjects suffering from osteoarthritis of the knee and/or hip were enrolled. For two weeks prior, then during and after treatment, subject pain was self-assessed using the visual scale (VS). In addition, subjects were globally assessed by a physician. All subjects, device operators and physicians were blinded as to whether subjects were treated with an active or sham device. Data collected from the study indicate both a decrease in VS pain scores and a significant improvement (p = 0.05) in physician assessment in subjects treated with active devices compared to those treated with the sham device. In 23 patients with pancreatitis, daily pain for at least 3 months, and no abuse of alcohol, the pain-relieving effect of electroacupuncture (13 patients) or transcutaneous electric nerve stimulation (TENS) (16 patients) was studied. In two prospective studies with a cross-over design, active acupuncture was compared with sham acupuncture, and TENS of the segmental points of the pancreas with sham treatment. Neither electroacupuncture nor TENS brought about pain relief that could substitute for or supplement medical treatment. To evaluate the efficacy of transcutaneous electrotherapy for chronic painful peripheral neuropathy in patients with type 2 diabetes.
                Thirty-one patients with symptoms and signs of peripheral neuropathy were randomized to the electrotherapy or sham treatment (control) group. The electrostimulation was given by a portable unit (H-Wave machine) than generated a biphasic, exponentially decaying waveform (pulse width 4 ms, 25-35 V, > or = 2 Hz). Patients treated each of their lower extremities for 30 min daily for 4 weeks at home. Nine patients from the sham-treatment group participated for a second period, during which all of them received the active electrotherapy. Patient's degree of pain and discomfort was graded on a scale of 0 to 5.
                In the sham-treated group (n = 13), the neuropathic symptoms improved in five (38%) patients, and the pain score declined from 2.92 +/- 0.13 to 2.38 +/- 0.26 (P < 0.04), suggesting a procedure-related placebo effect. In the electrotherapy group (n = 18), symptomatic improvement was seen in 15 (83%) cases, 3 of which were completely asymptomatic; the pain score declined from 3.17 +/- 0.12 to 1.44 +/- 0.25 (P < 0.01) and the posttreatment pain scores were considerably lower (P < 0.03), indicating a substantial treatment effect over and above any placebo influence. Patients in the electrotherapy group reported greater reduction in symptoms (52 +/- 7% vs. 27 +/- 10% in control subjects, P < 0.05) on an analog scale. Moreover, the electrotherapy decreased pain scores (from 3.0 +/- 0.62 to 1.56 +/- 0.32, P < 0.02) in nine patients who had received sham treatment earlier.
                A form of transcutaneous electrotherapy ameliorated the pain and discomfort associated with peripheral neuropathy. This novel modality offers a potential non-pharmacological treatment option. In small trials with control groups that receive no intervention, acupuncture has been reported to improve functional outcome after stroke. We studied effects of acupuncture and transcutaneous electrical nerve stimulation on functional outcome and quality of life after stroke versus a control group that received subliminal electrostimulation.
                In a multicenter randomized controlled trial involving 7 university and district hospitals in Sweden, 150 patients with moderate or severe functional impairment were included. At days 5 to 10 after acute stroke, patients were randomized to 1 of 3 intervention groups: (a) acupuncture, including electroacupuncture; (b) sensory stimulation with high-intensity, low-frequency transcutaneous electrical nerve stimulation that induces muscle contractions; and (c) low-intensity (subliminal) high-frequency electrostimulation (control group). A total of 20 treatment sessions were performed over a 10-week period. Outcome variables included motor function, activities of daily living function, walking ability, social activities, and life satisfaction at 3-month and 1-year follow-up.
                At baseline, patients in each group were closely similar in all important prognostic variables. At 3-month and 1-year follow-ups, no clinically important or statistically significant differences were observed between groups for any of the outcome variables. The 3 treatment modalities were all conducted without major adverse effects.
                When compared with a control group that received subliminal electrostimulation, treatment during the subacute phase of stroke with acupuncture or transcutaneous electrical nerve stimulation with muscle contractions had no beneficial effects on functional outcome or life satisfaction. Haemophiliacs suffer considerable pain when they bleed into their joints. This study investigated the use of transcutaneous electrical nerve stimulation (TENS) for relief of such pain. Thirty-six haemophiliac patients received either active or placebo TENS treatment. The intensity of pain was assessed before and after treatment using the McGill Pain Questionnaire. After 25 min of active treatment, 71% of the subjects reported at least 50% pain relief as measured by the McGill Pain Questionnaire. This compares with only 25% pain relief experienced by the placebo group. Transcutaneous electrical nerve stimulation (TENS) is a frequently applied therapy in chronic pain although evidence for effectiveness is inconclusive. Several types of TENS, based on different combinations of frequency, pulse duration and intensity, exist. The precise mechanism of action and the relevance of combinations of stimulus parameters are still unclear. To compare the effectiveness of three types of TENS we conducted a randomized, single blinded crossover trial. Patients received two times a 2-week period of daily TENS treatment, separated by a washout period of 2 weeks. In total, 180 chronic pain patients were randomized into three groups. In group 1, high frequency, low intensity TENS (HFT) was compared with high frequency, high intensity TENS (HIT). In groups 2 and 3, HFT and HIT were compared with a control TENS (COT). The order of applying the different modalities of TENS in each group was also randomized. Primary outcome was the patient's overall assessment of effectiveness and pain reduction (VAS). No differences were found in patient's assessment or pain reducing effect between the three groups, indicating no superiority of one type of TENS. In total, 56% continued TENS after the 2-week treatment period. At 6 months, 42% of all patients still used TENS. We concluded that there were no differences in effectiveness for the three types of TENS used in this study. Because no placebo group was included, no definite conclusions on effectiveness of TENS in general in the treatment of chronic pain could be made. Double blind, partial crossover.
                To evaluate the analgesic activity of a novel cranial electrostimulus in people with spinal cord injury (SCI).
                Hereward College, a residential centre that provides educational facilities for students with disabilities.
                Subjects with SCI experiencing chronic pain were randomly assigned into two groups, one of which received sham and the other transcranial electrostimulation treatment (TCET) on two occasions daily for four successive days. After a 'wash-out' period of 8 weeks all subjects returned and received the identical stimulus that the treated cohort received on the first arm of the study.
                Pain measurements applied before and after each session indicated that the pain decreased in the treated group to 51% of that reported at the commencement of treatment; reported pain intensity did not decrease significantly in the sham treated subjects. The same (sham) subject group reported experiencing 59% of the pain at the end of the second arm of the study (TCET) as on the first arm (sham). No significant differences were determined between the mood of all subjects estimated before and after each sham or TCET treatment session. The reported analgesic, and combined antidepressant and anxiolytic drug use in subjects receiving TCET on the second arm of the study, was 46% and 53% respectively of the average pre-study drug use. No similar decrease in the use of the drugs was noted in the same subjects after sham treatment on the first arm of the study. Salivary cortisol determinations made prior to and after each sham and treatment session implicated this corticoid in the pain-relieving mode of action of the treatment, but could not be associated with any changes in mood. Subjects receiving TCET had significantly higher urinary 3-methoxy-4-hydroxy-phenylglycol (MHPG) output after the TCET treatment period than sham stimulation, implicating increased central noradrenaline (NA) metabolism in the observed effects.
                The subjects reported less pain during, and immediately after receiving this transcranial treatment, although they were using less medication than when receiving sham treatment.
In this update, we could not confirm that transcutaneous electrostimulation is effective for pain relief. The current systematic review is inconclusive, hampered by the inclusion of only small trials of questionable quality. Appropriately designed trials of adequate power are warranted.