Can high frequency electrical stimulation of the skin (HFS) induce a sustained secondary hyperalgesia at the distal lower limb?
(2021) IASP Virtual Congress 2021 — Location: Online (16.June.2021)
Files
POSTER_IASP_HFS_FOOT_Louisien_Lebrun_landscape.pdf
Open Access - Adobe PDF
- 905.06 KB
Details
- Authors
- Abstract
- Background and Aims: High Frequency Stimulation (HFS) applied onto the human skin produces an increase in sensitivity to mechanical pinprick stimuli in the surrounding non-stimulated skin. This phenomenon is thought to be related to the secondary hyperalgesia caused by a lesion, and to be a consequence of central sensitization. Most previous studies have explored HFS-induced secondary hyperalgesia at the upper limb [1; 3]. The aim of this study was to characterize the change in mechanical pinprick sensitivity induced by HFS delivered to another body part, the distal end of the lower limb. Methods: 32 healthy volunteers (15 women and 17 men aged between 20 and 30; mean 23,7) were included in the experiment. Half of the participants received HFS on the volar forearm (10 cm distal from the cubital fossa, dermatomes C6-C7-T1) [2; 4]. The other half received HFS on the lateral side of the foot (dermatomes L5-S1) [2]. The stimulation consisted of 5 trains of 100 Hz pulses (pulse width: 2 ms) lasting 1 s. The electrode consisted of 16 blunt, stainless steel pins with a diameter of 0,2 mm protruding 1 mm from the base (MRC Systems, GmbH, Heidelberg University, Germany). The time interval between each train onset was 10 s. The intensity of stimulation corresponded to 20 times the detection threshold to a single pulse (forearm: 0.12 +/-0.06 mA [mean +/- SD], foot : 0.30 +/-0.10 mA). Pinprick sensitivity was assessed before HFS and 30 min, 60 min, 90 min, 120 min, 180 min and 240 min after HFS by asking participants to rate the intensity of a 128 mN pinprick stimulus (0.25 mm probe) applied perpendicular to the conditioned skin. The area of increased pinprick sensitivity was assessed along eight radial axes at each time point. Results: Both HFS applied to the volar forearm and HFS applied to the lateral foot dorsum induced a significant increase in pinprick sensitivity, which was present both up to 240 min at the forearm and the foot. The increase in sensitivity was greater at the forearm compared to the foot dorsum (p < .05). The area of increased sensitivity was also greater at the forearm as compared to the foot (p = 0,003). Conclusions: HFS can be used to explore secondary hyperalgesia at the lower limbs. However, the change in pinprick sensitivity induced by HFS at the foot is not as strong as the change in pinprick sensitivity induced by HFS at the volar forearm. This could be due to differences at peripheral or central level, including differences in epidermal nerve fiber density, differences in skin thickness, differences in the daily exposures to stimuli, and/or differences in the central processing of nociceptive input originating from the upper and lower limbs. References: [1] Klein T, Stahn S, Magerl W, Treede RD. The role of heterosynaptic facilitation in long-term potentiation (LTP) of human pain sensation. Pain 2008;139(3):507-519. [2] Lee M, McPhee R, Stringer MJCATOJotAAoCA, Anatomists tBAoC. An evidence?based approach to human dermatomes. 2008;21(5):363-373. [3] van den Broeke EN, Gousset S, Bouvy J, Stouffs A, Lebrun L, van Neerven SGA, Mouraux A. Heterosynaptic facilitation of mechanical nociceptive input is dependent on the frequency of conditioning stimulation. J Neurophysiol 2019. [4] van den Broeke EN, Mouraux A. High-frequency electrical stimulation of the human skin induces heterotopical mechanical hyperalgesia, heat hyperalgesia, and enhanced responses to nonnociceptive vibrotactile input. J Neurophysiol 2014;111(8):1564-1573. Conflicts of Interest: The authors have no conflict of interest to declare Source of Financial Support for the Project: This study was supported by a funding from the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement No [777500]. This Joint Undertaking receives support from the European Union’s Horizon 2020 research and innovation program and EFPIA. www.imi.europa.eu; www.imi-paincare.eu. The statements and opinions presented here reflect the author's view and neither IMI nor the European Union, EFPIA, or any Associated Partners are responsible for any use that may be made of the information contained therein.
- Affiliations
Citations
Lebrun, L., Stouffs, A., Nava, C., van den Broeke, E., & Mouraux, A. (2021). Can high frequency electrical stimulation of the skin (HFS) induce a sustained secondary hyperalgesia at the distal lower limb? IASP Virtual Congress 2021, Online. https://hdl.handle.net/2078.5/111348