Szecsi Johann, Fornusek Ché, Krause Phillip, Straube Andreas
Center for Sensorimotor Research, Department of Neurology, Ludwig-Maximillians University, Munich, Germany.
Arch Phys Med Rehabil. 2007 Mar;88(3):338-45. doi: 10.1016/j.apmr.2006.12.026.
To determine the efficacy of using modulated middle frequency alternating current (MFAC) muscle stimulation for functional electric stimulation-propelled cycling by people with spinal cord injury (SCI) compared with the conventional method of using standard low-frequency rectangular pulses (LFRP).
Repeated-measures.
Laboratory setting.
Eleven otherwise healthy volunteer subjects with SCI (8 with American Spinal Injury Association [ASIA] grade A, 3 with ASIA grade B).
To evaluate cycling-relevant differences between LFRP and modulated MFAC stimulation, we exposed participants to isometric measurements and cycling experiments performed during both 20 Hz LFRP and 4 KHz modulated with 50 Hz MFAC.
We recorded maximal isometric torque, maximal dynamic work during 20 minutes of ergometer cycling, and perceived discomfort for each of the 2 stimulation patterns.
Both the isometric torque (P<.02) and work generated (P<.001) during MFAC stimulation were significantly lower than during standard LFRP stimulation. Four participants reported discomfort and 1 of them also developed skin burns during MFAC stimulation.
Our findings suggest that in SCI subjects, stimulated cycling with low frequency is generally more effective than cycling with modulated MFAC in terms of torque, work, and pain sensation.
确定与使用标准低频矩形脉冲（LFRP）的传统方法相比，脊髓损伤（SCI）患者使用调制中频交流电（MFAC）肌肉刺激进行功能性电刺激驱动骑行的效果。
重复测量。
实验室环境。
11名其他方面健康的SCI志愿者受试者（8名美国脊髓损伤协会[ASIA] A级，3名ASIA B级）。
为了评估LFRP和调制MFAC刺激之间与骑行相关的差异，我们让参与者在20 Hz LFRP和50 Hz调制的4 KHz MFAC期间进行等长测量和骑行实验。
我们记录了两种刺激模式下的最大等长扭矩、测力计骑行20分钟期间的最大动态功以及感知到的不适程度。
MFAC刺激期间的等长扭矩（P<.02）和产生的功（P<.001）均显著低于标准LFRP刺激期间。4名参与者报告了不适，其中1名在MFAC刺激期间还出现了皮肤烧伤。
我们的研究结果表明，对于SCI受试者，在扭矩、功和疼痛感觉方面，低频刺激骑行通常比调制MFAC骑行更有效。
