The Neurophysiological Effects of Cervical Transcutaneous Spinal Cord Stimulation With and Without a High Frequency Carrier in Able-Bodied Adults.

IF 2.2 3区医学 Q3 ENGINEERING, BIOMEDICAL

Artificial organs Pub Date : 2025-06-03 DOI:10.1111/aor.15031

Frances Gawne, Sarah Massey, Lynsey Duffell

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引用次数: 0

Abstract

Background: Transcutaneous spinal cord stimulation (tSCS) is a promising avenue in spinal cord injury (SCI) rehabilitation; however, high currents are required to excite afferents in the spinal cord roots, which patients may not tolerate. Modulating tSCS pulses with a kHz carrier frequency (kHz-tSCS) may be used to reduce discomfort; however, the way that kHz-tSCS interacts with neural networks, compared to unmodulated pulses (conv-tSCS), is largely unknown.

Method: Ten able-bodied participants received conv-tSCS, kHz-tSCS, and sham interventions for 20 min over the C7/T1 vertebrae. Charge delivery of both waveforms was measured. Posterior root reflexes (PRRs) and motor-evoked potentials (MEPs) were recorded from the Flexor Carpi Radialis (FCR), Extensor Carpi Radialis Longus (ECRL), Flexor Carpi Ulnaris (FCU), and Brachioradialis (BR). PRR and MEP peak-peak amplitudes were measured at baseline, 0-, 15-, and 30-min post-intervention.

Results: The charge required to activate posterior roots with kHz-tSCS was 3.8 times higher than with conv-tSCS (p < 0.001). Differences in PRR amplitude were found in the FCR between conv-tSCS and kHz-tSCS at 0- and 15-min post-intervention (p < 0.028). PRR inhibition was found in the FCR between baseline and 30-min post-intervention with conv-tSCS and the sham intervention (p < 0.037). No change in PRR amplitudes was found for kHz-tSCS. No other muscle showed any differences in PRR responses between intervention groups. Neither intervention caused any effect in MEP responses across time or between intervention groups.

Conclusions: kHz-tSCS was a less efficient waveform for stimulation. Differences in effects on spinal excitability were found to be inconclusive, and conv-tSCS and kHz-tSCS had no effect on corticospinal excitability. Significant PRR inhibition in the FCR was found with this experimental setup even when no stimulation was applied, suggesting a natural reduction in spinal excitability caused by participants laying supine for an extended period. Future research should consider how participant positioning could affect neural excitability.

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健全成人有或无高频载体的颈经皮脊髓刺激的神经生理效应。

背景：经皮脊髓刺激（tSCS）是一种很有前途的脊髓损伤（SCI）康复途径；然而，需要高电流来激发脊髓根的传入神经，这可能是患者无法忍受的。以千赫载波频率调制tSCS脉冲（kHz-tSCS）可用于减少不适；然而，与未调制脉冲（convtscs）相比，kHz-tSCS与神经网络的相互作用方式在很大程度上是未知的。方法：10名身体健全的参与者在C7/T1椎体上分别接受convt - tscs、kHz-tSCS和假干预，干预时间为20分钟。测量了两种波形的电荷传递。记录桡侧腕屈肌（FCR）、桡侧腕长伸肌（ECRL）、尺侧腕屈肌（FCU）和肱桡肌（BR）的后根反射（PRRs）和运动诱发电位（MEPs）。在基线、干预后0、15和30分钟测量PRR和MEP峰幅。结果：使用kHz-tSCS激活后根所需的电荷比使用反向tscs高3.8倍(p)。结论：kHz-tSCS是一种效率较低的刺激波形。对脊髓兴奋性影响的差异尚无定论，convt - tscs和kHz-tSCS对皮质脊髓兴奋性没有影响。即使在没有刺激的情况下，FCR中也发现了显著的PRR抑制，这表明参与者长时间仰卧会导致脊髓兴奋性的自然降低。未来的研究应该考虑参与者的位置如何影响神经兴奋性。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Artificial organs 工程技术-工程：生物医学

CiteScore

4.30

自引率

12.50%

发文量

303

审稿时长

4-8 weeks

期刊介绍： Artificial Organs is the official peer reviewed journal of The International Federation for Artificial Organs (Members of the Federation are: The American Society for Artificial Internal Organs, The European Society for Artificial Organs, and The Japanese Society for Artificial Organs), The International Faculty for Artificial Organs, the International Society for Rotary Blood Pumps, The International Society for Pediatric Mechanical Cardiopulmonary Support, and the Vienna International Workshop on Functional Electrical Stimulation. Artificial Organs publishes original research articles dealing with developments in artificial organs applications and treatment modalities and their clinical applications worldwide. Membership in the Societies listed above is not a prerequisite for publication. Articles are published without charge to the author except for color figures and excess page charges as noted.