Comparison of Effects of Transcutaneous Electrical Nerve Stimulation of Auricular, Somatic, and the Combination of Auricular and Somatic Acupuncture Points on Experimental Pain Threshold

Abstract

This study compared the effects of high intensity, low frequency transcutaneous electrical nerve stimulation of auricular, somatic, and combined auricular and somatic acupuncture points on experimental pain threshold measured at the wrist. Sixty-seven healthy adults, aged 18 to 39 years, were assigned randomly to one of four groups: 1) the Auricular Group (n = 17) received TENS to auricular acupuncture points, 2) the Somatic Group (n = 17) received TENS to somatic acupuncture points, 3) the Combined Group (n = 17) received TENS to both auricular and somatic acupuncture points, and 4) the Control Group (n = 16) received no TENS and served as controls. Pain threshold was measured immediately before and after treatment or rest. Pain threshold significantly increased (p less than .05) in the Auricular, Somatic, and Combined Groups following treatment, with no statistically significant differences in mean pain threshold change scores among treatment groups. The Control Group demonstrated no statistically significant change in pain threshold. The results indicate that TENS applied to any of the three sets of acupuncture points equally increases pain threshold, thus possibly increasing options in choosing stimulation sites for treating patients with pain.

Dose-specific Effects of Transcutaneous Electrical Nerve Stimulation (TENS) on Experimental Pain

“…26,49 Overall, TENS showed conflicting evidence of efficacy. Twenty-four trials reported positive outcomes 28,33,[36][37][38][39][41][42][43]45,[47][48][49][50]52,53,[55][56][57][58]61,64,65 (ie, a significant difference favoring TENS compared with an inactive control) and 19 trials reported negative outcomes 26,27,[29][30][31][32]34,35,40,44,46,51,54,59,60,62,63,66 (ie, no difference between TENS and an inactive control). No trials reported a significant difference favoring the control group.…”

“…Similar proportions of positive and negative trials recorded the outcome measurement with TENS switched on, [26][27][28][29][30][31][32][33]36,41,45,[49][50][51][52][54][55][56][57][58]63,68 switched off, 34,35,[37][38][39][40][42][43][44][46][47][48] or poststimulation. 53,[59][60][61][62]64,65 Specifically, with TENS switched on, 13 of 24 trials (54%) 28,33,36,41,45,49,50,52,[55][56]…”

The History, Mechanism, and Clinical Application of Auricular Therapy in Traditional Chinese Medicine

“…Noling et al (1988) found that a low frequency (1 Hz) with a high intensity (1000 μ A) elevated the pain threshold, and this effect peaked 5 to 10 min after stimulation and lasted from several hours to a few days [ 47 ]. Lein et al (1989) used TENS and also had the same result as above [ 48 ]. Sator-Katzenschlager et al (2003) found that auricular electrical stimulation is better than auricular manual acupuncture when decreasing pain [ 49 ].…”

Effect of Transcutaneous Electrical Nerve Stimulation for the Management of Burn Pruritus: A Pilot Study

“…Recent studies indicate that stimulating acupuncture points as a treatment for pain may be even more effective than TENS on other somatic points. 10,18,19 With respect to this study, the gate control theory best represents the affect of TENS on patients with burn pruritus. The exogenous stimulus provided by TENS appeared to override the patients' perception of pruritus.…”