Kawamura H1, Nishigami T1, Tsujishita M2, Ito K2, Ohya N3, Takagi M4
1Konan Women's University, Department of Physical Therapy, Faculty of Nursing and Rehabilitation, Kobe, Japan, 2Naragakuen University, Nara, Japan, 3Shonan University of Medical Sciences, Yokohama, Japan, 4Kanagawa University of Human Services, Yokosuka, Japan
Background: There are cases when transcutaneous electrical nerve stimulation (TENS) cannot be performed directly at the pain site for reasons such as strong allodynia or bleeding or an open wound at the affected site. In such cases, treatment using stimulation contralateral to the pain site or the same dermatome is effective.
Stimulation intensities used in TENS include a comfortable stimulation intensity based on gate control theory and a stimulation intensity accompanying the rather strong pain of diffuse noxious inhibitory controls (DNICs), but there are no reports comparing the analgesic effects under different stimulation intensities.
Purpose: The purpose of this study was to investigate the effective intensity for TENS contralateral to the pain site.
Methods: The subjects were 10 healthy adult women (21.8±0.4 years old).
The study protocol called for 60 s rest as baseline, followed by heat stimulation for 60 s with 47°C conductive heat from a Peltier element device using a thermal algometer to create quantitative pain in advance on the dorsal side of the left wrist as controls. Next, for analgesia, TENS was performed to a dermatome on the dorsal side of the right wrist, which is contralateral to the pain site on the dorsal side of the left wrist and at the same dermatome level, at three different intensities randomly: TENS of a comfortable stimulation intensity (frequency 20 Hz, wavelength 200 µs, current duration 60 s); TENS of the intensity at pain threshold; and TENS of the intensity inducing maximum pain. There was a rest of 5 min before each TENS intervention, and a 90 s period of rest after the completion of all TENS interventions.
The treatment effect was judged using a visual analogue scale (VAS) and high frequency (HF), low frequency/high frequency (LF/HF) heart rate variability analysis to ascertain changes in autonomic nervous function.
For VAS and HF, LF/HF, statistical analysis comparing the control and the three TENS intensities was conducted based on one-way analysis of variance and multiple comparisons, with the level of significance set at 5%.
Results: VAS was significantly lower with the TENS of the intensity inducing maximum pain than with the control.
No significant changes were seen in HF or LF/HF, but for HF, the TENS of the intensity inducing maximum pain tended to be higher than the control.
Conclusion(s): The intensity of TENS to the dorsal side of the right wrist contralateral to the left pain site was effective at an intensity similar to that of DNICs.
Implications: By establishing an effective stimulation intensity for TENS contralateral to a pain site, TENS can likely be started earlier to a site contralateral to the pain site to relieve pain, contributing to shorter durations of analgesic treatment.
Keywords: Transcutaneous electrical nerve stimulation, Contralateral site, Visual analogue scale
Funding acknowledgements: Unfunded
Stimulation intensities used in TENS include a comfortable stimulation intensity based on gate control theory and a stimulation intensity accompanying the rather strong pain of diffuse noxious inhibitory controls (DNICs), but there are no reports comparing the analgesic effects under different stimulation intensities.
Purpose: The purpose of this study was to investigate the effective intensity for TENS contralateral to the pain site.
Methods: The subjects were 10 healthy adult women (21.8±0.4 years old).
The study protocol called for 60 s rest as baseline, followed by heat stimulation for 60 s with 47°C conductive heat from a Peltier element device using a thermal algometer to create quantitative pain in advance on the dorsal side of the left wrist as controls. Next, for analgesia, TENS was performed to a dermatome on the dorsal side of the right wrist, which is contralateral to the pain site on the dorsal side of the left wrist and at the same dermatome level, at three different intensities randomly: TENS of a comfortable stimulation intensity (frequency 20 Hz, wavelength 200 µs, current duration 60 s); TENS of the intensity at pain threshold; and TENS of the intensity inducing maximum pain. There was a rest of 5 min before each TENS intervention, and a 90 s period of rest after the completion of all TENS interventions.
The treatment effect was judged using a visual analogue scale (VAS) and high frequency (HF), low frequency/high frequency (LF/HF) heart rate variability analysis to ascertain changes in autonomic nervous function.
For VAS and HF, LF/HF, statistical analysis comparing the control and the three TENS intensities was conducted based on one-way analysis of variance and multiple comparisons, with the level of significance set at 5%.
Results: VAS was significantly lower with the TENS of the intensity inducing maximum pain than with the control.
No significant changes were seen in HF or LF/HF, but for HF, the TENS of the intensity inducing maximum pain tended to be higher than the control.
Conclusion(s): The intensity of TENS to the dorsal side of the right wrist contralateral to the left pain site was effective at an intensity similar to that of DNICs.
Implications: By establishing an effective stimulation intensity for TENS contralateral to a pain site, TENS can likely be started earlier to a site contralateral to the pain site to relieve pain, contributing to shorter durations of analgesic treatment.
Keywords: Transcutaneous electrical nerve stimulation, Contralateral site, Visual analogue scale
Funding acknowledgements: Unfunded
Topic: Electrophysical & isothermal agents; Pain & pain management
Ethics approval required: Yes
Institution: The Konan Women’s University
Ethics committee: The Konan Women’s University Ethics Committee
Ethics number: 2014205
All authors, affiliations and abstracts have been published as submitted.
