Physiotherapy Program, Faculty of Health Sciences, University of Ottawa, Canada; School of Rehabilitation, Faculty of Medicine, University of Montreal, Canada; Research Centre, Montreal Rehabilitation Institute, Montreal, Canada.
J Electromyogr Kinesiol. 1994;4(2):116-25. doi: 10.1016/1050-6411(94)90033-7.
The present study was conducted on eight normal subjects in order to evaluate the effects of transcutaneous electrical nerve stimulation (TENS); 99 Hz, 250 μs pulse duration, applied over either the common peroneal (CPN) or sural nerve, on the H-reflex of the soleus (SO), gastrocnemius medialis (GM) and gastrocnemius lateralis (GL) muscles. Within each session, SO, GL and GM H-reflexes were recorded before (for 5 min), during (for 30 min) and after (for 10 min) TENS was applied at twice the sensory threshold for perception. It was found that, on average, while the stimulation was administered on the CPN: (a) the GL H-reflex amplitude increased by 40% (Friedman test: χ(2) = 11.71, P < 0.05); (b) the SO H-reflex decreased (≥ 10% H(ctrl)), although not in a statistically significant manner, in five of eight subjects; and (c) the GM H-reflex remained, overall, relatively stable. No significant effects of TENS over the sural nerve were found on any of the investigated muscles. The finding of increased H-reflex amplitudes in GL during TENS made it less likely that CPN stimulation had reciprocal inhibitory effects. However, such an increase could be attributed to a selective effect (such as a decrease in the recruitment threshold) on type II motoneurons of the GL. Furthermore, the topographical effects observed on the GL during TENS may reflect selective local effects due to stimulation of a sensory branch of the CPN, the lateral sural nerve, which mainly innervates the skin overlying the GL. The absence of effects noted on the GM during TENS further supports this hypothesis as the cutaneous afferents overlying that muscle were not stimulated. The repetitive cutaneous stimulation over the sural nerve, at the lateral malleolus, may have been too distal to stimulate the cutaneous receptors overlying the SO.
本研究旨在评估经皮神经电刺激（TENS）对腓总神经（CPN）或腓肠神经刺激时比目鱼肌（SO）、腓肠肌内侧（GM）和外侧（GL）H 反射的影响。在每个实验中，在 TENS 应用于感觉阈的两倍（用于感知）之前（5 分钟）、期间（30 分钟）和之后（10 分钟）记录 SO、GL 和 GM H 反射。结果发现，在 CPN 刺激时，平均而言：（a）GL H 反射幅度增加了 40%（弗里德曼检验：χ²=11.71，P<0.05）；（b）SO H 反射在 8 个受试者中的 5 个中虽然没有统计学意义但下降（≥10%H（ctrl））；（c）GM H 反射总体上保持相对稳定。在所有研究的肌肉中，TENS 对腓肠神经没有明显的影响。TENS 期间 GL 中 H 反射幅度增加，使得 CPN 刺激不太可能产生交互抑制作用。然而，这种增加可能归因于对 GL 中 II 型运动神经元的选择性效应（例如募集阈值降低）。此外，TENS 期间在 GL 上观察到的空间效应可能反映了由于 CPN 的感觉分支（外侧腓肠神经）刺激而导致的选择性局部效应，该神经主要支配 GL 上方的皮肤。TENS 期间 GM 上未观察到效应进一步支持了这一假设，因为该肌肉上方的皮肤传入神经未被刺激。在外侧踝处的腓肠神经上进行重复性皮肤刺激可能太远离刺激 SO 上方的皮肤感受器。
