Division of Rehabilitation Sciences, University of Texas Medical Branch in Galveston, Galveston, TX, USA.
Top Stroke Rehabil. 2013 Jul-Aug;20(4):299-307. doi: 10.1310/tsr2004-299.
The optimal parameters of neuromuscular electrical stimulation (NMES) for recovery of hand function after stroke are not known. This clinical pilot study examined whether higher or lower frequencies are more effective for improving fine motor control of the hand in a chronic poststroke population.
A 1-month, 4 times per week, in-home regimen of either a high-frequency (40 Hz) or low-frequency (20 Hz) NMES program was applied to the hemiplegic thenar muscles of 16 persons with chronic stroke. Participants were identified a priori as having a low level of function (LF) or a high level of function (HF). Outcome measures of strength, dexterity, and endurance were measured before and after participation in the regimen.
LF subjects showed no significant changes with either the high- or the low-frequency NMES regimen. HF subjects showed significant changes in strength, dexterity, and endurance. Within this group, higher frequencies of stimulation yielded strength gains and increased motor activation; lower frequencies affected dexterity and endurance.
The results suggest that higher frequencies of stimulation could be more effective in improving strength and motor activation properties and that lower frequencies may affect coordination and endurance changes. Results also indicate that persons with a higher functional level of recovery may respond more favorably to NMES regimens, but further study with larger patient groups is warranted.
神经肌肉电刺激（NMES）在手功能恢复方面的最佳参数尚不清楚。本临床初步研究探讨了在慢性卒中人群中，较高或较低频率是否更有利于改善手部精细运动控制。
16 名慢性卒中患者接受为期 1 个月、每周 4 次的高频（40 Hz）或低频（20 Hz）NMES 方案，应用于偏瘫鱼际肌。参与者预先确定为功能水平低（LF）或功能水平高（HF）。在参与方案前后测量力量、灵巧性和耐力的结局测量指标。
LF 受试者在高频和低频 NMES 方案中均未显示出显著变化。HF 受试者在力量、灵巧性和耐力方面均有显著变化。在该组中，较高频率的刺激可产生力量增益和增加运动激活；较低的频率影响灵巧性和耐力。
结果表明，较高频率的刺激可能更有效地改善力量和运动激活特性，而较低的频率可能影响协调和耐力的变化。结果还表明，功能恢复水平较高的患者可能对 NMES 方案更有反应，但需要进一步的、更大患者群体的研究。
