Faculty of Health and Social Sciences, Leeds Metropolitan University, UK.
Clin J Pain. 2013 Feb;29(2):146-53. doi: 10.1097/AJP.0b013e3182579919.
Strong nonpainful transcutaneous electrical nerve stimulation (TENS) is prerequisite to a successful analgesic outcome although the ease with which this sensation is achieved is likely to depend on the magnitude of current amplitude (mA) between sensory detection threshold (SDT) and pain threshold, that is, the current window.
To measure the current window and participant's perception of the comfort of the TENS sensation at different body sites.
A repeated measure cross-over study was conducted using 30 healthy adult volunteers. Current amplitudes (mA) of TENS [2 pulses per second (pps); 30 pps; 80 pps] at SDT, pain threshold, and strong nonpainful intensities were measured at the tibia (bone), knee joint (connective tissue), lower back [paraspinal (skeletal) muscle], volar surface of forearm (nerve) and waist (fat). The amplitude to achieve a strong nonpainful intensity was represented as a percentage of the current window. Data were analyzed using repeated measures analysis of variance.
Effects were detected for body site and frequency for SDT (P<0.001, P=0.018, respectively), current window (P<0.001, P<0.001, respectively), and strong nonpainful TENS as a percentage of the current window (P=0.002, P<0.001, respectively). The current window was larger for the knee joint compared with tibia (difference [95% confidence interval]=12.76 mA [4.25, 21.28]; P=0.001) and forearm (10.33 mA [2.62, 18.40]; P=0.006), and for the lower back compared with tibia (12.10 mA [1.65, 22.52]; P=0.015) and forearm (9.65 mA [1.06, 18.24]; P=0.019). The current window was larger for 2 pps compared with 30 pps (P<0.001) and 80 pps (P<0.001). Participants rated strong nonpainful TENS as most comfortable at the lower back (P<0.001) and least comfortable at the tibia and forearm (P<0.001).
TENS is most comfortable and easiest to titrate to a strong nonpainful intensity when applied over areas of muscle and soft tissue.
虽然实现这种感觉的容易程度可能取决于感觉检测阈值（SDT）和疼痛阈值之间的电流幅度（mA），即电流窗口，但强烈无痛的经皮神经电刺激（TENS）是成功镇痛效果的前提。
测量不同身体部位的 TENS 感觉舒适度的电流窗口和参与者的感知。
采用 30 名健康成年志愿者的重复测量交叉研究。在胫骨（骨）、膝关节（结缔组织）、下背部[脊柱旁（骨骼）肌肉]、前臂掌侧（神经）和腰部（脂肪）处测量 TENS 的电流幅度（mA）[2 脉冲/秒（pps）;30pps;80pps]在 SDT、疼痛阈值和强烈无痛强度下。达到强烈无痛强度的幅度表示为电流窗口的百分比。使用重复测量方差分析对数据进行分析。
身体部位和频率对 SDT 有影响（P<0.001，P=0.018），电流窗口（P<0.001，P<0.001），以及 TENS 作为电流窗口的百分比（P=0.002，P<0.001）。与胫骨（差异[95%置信区间]=12.76 mA [4.25，21.28]；P=0.001）和前臂（10.33 mA [2.62，18.40]；P=0.006）相比，膝关节的电流窗口更大，与胫骨（12.10 mA [1.65，22.52]；P=0.015）和前臂（9.65 mA [1.06，18.24]；P=0.019）相比，下背部的电流窗口更大。与 30pps（P<0.001）和 80pps（P<0.001）相比，2pps 的电流窗口更大。参与者认为强烈无痛的 TENS 在腰部最舒适（P<0.001），在胫骨和前臂最不舒服（P<0.001）。
当应用于肌肉和软组织区域时，TENS 最舒适，最容易调节至强烈无痛强度。
