Center for Interdisciplinary Pain Medicine, Department of Anesthesiology, University Hospital of Regensburg, Franz-Josef-Strauss-Allee 11, 93053, Regensburg, Germany.
Center for Interdisciplinary Pain Medicine, Department of Anesthesiology, University Hospital of Regensburg, Franz-Josef-Strauss-Allee 11, 93053, Regensburg, Germany.
J Neurosci Methods. 2019 May 15;320:44-49. doi: 10.1016/j.jneumeth.2019.03.009. Epub 2019 Mar 11.
The nociceptive withdrawal reflex (NWR) is a polysynaptic spinal reflex protecting the body from harmful stimuli. Two different methods to assess its' threshold (NWR-T) have been part of clinical trials concerning the evaluation of the nociceptive system in the human body. NWR-T's are gathered by stimulation at the sole of the foot and over the sural pathway. Consequently, EMG analyzes the muscle activity over the biceps femoris and tibialis anterior muscle. Past studies favor stimulation at the sole of the foot.
The two methods were compared concerning retest-reliability and subjective pain ratings. The retest-reliability was tested over a period of 21 days using an up-down staircase method. Reliability was evaluated with a Bland Altman agreement analysis. Subjective pain ratings were evaluated with a numeric rating scale (NRS).
NWR-T assessment was successful for all subjects. The EMG muscle activity had larger reflex amplitudes for measurements of the tibialis anterior muscle. NWR-T values showed greater variability than NRS values.
The retest-reliability over a period of 21 days showed stable NWR-T results for both stimulation sites, but superior reliability was gathered with stimulation at the sole of the foot. Subjects rated stimulation over the sural pathway as more painful.
The NWR-T upholds reliable measurements over a longer period of time and seems to be a stable measure for pain condition. Reliability estimations, EMG recordings, and subject's rating show stimulation at the sole of the foot could be the better choice.
伤害性退缩反射（NWR）是一种多突触脊髓反射，可保护身体免受有害刺激。两种不同的评估其阈值（NWR-T）的方法已成为涉及人体痛觉系统评估的临床试验的一部分。NWR-T 通过足底和腓肠神经通路的刺激来收集。因此，肌电图分析股二头肌和胫骨前肌的肌肉活动。过去的研究倾向于足底刺激。
比较了两种方法的重测可靠性和主观疼痛评分。使用升降梯法在 21 天的时间内测试重测可靠性。可靠性通过 Bland Altman 一致性分析进行评估。主观疼痛评分采用数字评分量表（NRS）进行评估。
所有受试者的 NWR-T 评估均成功。对于胫骨前肌的测量，EMG 肌肉活动具有更大的反射幅度。NWR-T 值的变异性大于 NRS 值。
在 21 天的时间内，两种刺激部位的重测可靠性均显示出稳定的 NWR-T 结果，但足底刺激的可靠性更高。受试者认为腓肠神经通路的刺激更疼痛。
NWR-T 可在较长时间内进行可靠测量，似乎是一种稳定的疼痛状况衡量标准。可靠性估计、肌电图记录和受试者的评分均表明，足底刺激可能是更好的选择。
