Bell K R, Lehmann J F
Arch Phys Med Rehabil. 1987 Aug;68(8):490-3.
The local application of cold has been used to decrease spasticity and facilitate neuromuscular function, but previous attempts to identify its effect on the stretch reflex have not been entirely successful. We examined the effects of cold on the Hoffmann (H) reflex and on the tendon tap (T) reflex in 16 subjects. A series of H/M recruitment curves and T-reflexes were recorded via surface EMG electrodes before and during cooling of the triceps surae. Skin and intramuscular temperatures were recorded with average decreases of 18.4C and 12.1C, respectively. Peak-to-peak amplitude of the M, H, and T compound action potentials (CAPs) was measured. In all cases, the amplitude of the maximal M-wave decreased (p less than 0.001) in response to cooling. These changes in the recording of CAPs should be considered when cooling experiments result in alterations in H or T waveforms. When using the M-wave as a covariant in our analysis, there were no significant changes in the H-reflex amplitude; the height of CAPs elicited by T decreased (p = 0.025). Our findings do not support earlier claims that simple cooling facilitates the excitatory alpha motoneuron pool as measured by the H-reflex; we do confirm that muscle spindle activity, as measured by the T-reflex, is decreased by muscle cooling.
局部冷敷已被用于减轻痉挛并促进神经肌肉功能，但先前确定其对牵张反射影响的尝试并不完全成功。我们研究了冷敷对16名受试者霍夫曼（H）反射和腱反射（T）的影响。在腓肠肌冷却前和冷却过程中，通过表面肌电图电极记录了一系列H/M募集曲线和T反射。记录了皮肤和肌肉内温度，平均降幅分别为18.4℃和12.1℃。测量了M波、H波和T复合动作电位（CAP）的峰峰值幅度。在所有情况下，冷却后最大M波的幅度均下降（p<0.001）。当冷却实验导致H波或T波波形改变时，应考虑CAP记录中的这些变化。在我们的分析中，将M波用作协变量时，H反射幅度没有显著变化；T引发的CAP高度下降（p = 0.025）。我们的研究结果不支持早期的说法，即通过H反射测量，单纯冷却会促进兴奋性α运动神经元池；我们确实证实，通过T反射测量，肌肉冷却会降低肌梭活动。
