Svilpauskaite Jovita, Truffert André, Vaiciene Nerija, Magistris Michel R
Department of Neurology, Kaunas University of Medicine, Lithuania.
Medicina (Kaunas). 2006;42(4):300-13.
Methods for assessing small peripheral nerve fiber function objectively are limited. The cutaneous silent period (CuSP), a transient suppression of electromyographic voluntary activity that follows painful stimuli, could serve as an objective functional measure of the A delta fibers.
To establish normal values of CuSP, to compare these values to those in the literature and to discuss the yield of the CuSP in pathological conditions.
We investigated the CuSP of the upper and lower limbs of 40 normal subjects.
We observed that the spinal circuitry mediating the CuSP is mainly unilateral and restricted to one limb, and that CuSP latency decreases and duration increases with increasing stimulus intensity, then CuSP stabilizes with strong stimuli. In an additional study, we observed that painful cutaneous stimuli are either inhibitory, causing a pause in an ongoing contraction (CuSP), or excitatory, inducing a contraction of a muscle at rest (RIII). Inhibition and excitation have similar timings.
The method for studying the CuSP is simple and well tolerated; it is useful to study A delta fibers in peripheral neuropathies and the central circuitry of this cutaneous nociceptive response in conditions affecting the spinal cord. Comparison of CuSP studies suggests the need for a standardization of the method.
客观评估外周小神经纤维功能的方法有限。皮肤静息期（CuSP）是一种在疼痛刺激后出现的肌电图随意活动的短暂抑制，可作为Aδ纤维的一种客观功能指标。
建立CuSP的正常值，将这些值与文献中的值进行比较，并讨论CuSP在病理状态下的应用价值。
我们对40名正常受试者的上肢和下肢的CuSP进行了研究。
我们观察到，介导CuSP的脊髓回路主要是单侧的，且局限于一个肢体，并且CuSP潜伏期随刺激强度增加而缩短，持续时间随刺激强度增加而延长，然后在强刺激下CuSP趋于稳定。在另一项研究中，我们观察到疼痛性皮肤刺激要么是抑制性的，导致正在进行的收缩暂停（CuSP），要么是兴奋性的，诱导静息肌肉收缩（RIII）。抑制和兴奋具有相似的时间。
研究CuSP的方法简单且耐受性良好；它对于研究外周神经病变中的Aδ纤维以及在影响脊髓的疾病中这种皮肤伤害性反应的中枢回路很有用。CuSP研究的比较表明需要对该方法进行标准化。
