Spinal Cord Injury and Disorders Center, Hunter Holmes McGuire VAMC, Richmond, VA, USA.
NeuroRehabilitation. 2013;33(1):161-70. doi: 10.3233/NRE-130941.
To investigate the effects of regional thigh composition that result in different responses to current amplitude among individuals with spinal cord injury (SCI) during applications of surface neuromuscular electrical stimulation (NMES) to evoke dynamic leg extension.
Cross-sectional.
Academic Settings.
Five males with chronic motor complete SCI completed 3 visits of NMES to determine the current amplitude required to evoke full knee extension. The participants underwent magnetic resonance imaging of both thighs to measure skeletal muscle cross-sectional area (CSA), thigh subcutaneous adipose tissue (SAT) and intramuscular fat (IMF). Applicants were classified into high (n = 3) and low-responders (n = 2) based on the determined current amplitude.
The low-responders required 48-59% greater current amplitude to complete the same task as the high-responders. Low-responders had greater thigh SAT CSA (51-56%) than the high-responders with SCI. After adjusting to whole thigh CSA, IMF CSA was significantly greater in the low- responders; whereas skeletal muscle CSA was lower compared to the high-responders.
The findings suggest that thigh SAT and IMF act as insulation against propagation of current during surface NMES applications in individuals with SCI.
探究不同个体在接受表面神经肌肉电刺激（NMES）以诱发动态腿部伸展时，大腿区域组成的差异对电流幅度的反应，这些差异与脊髓损伤（SCI）有关。
横断面研究。
学术环境。
5 名慢性完全性运动 SCI 男性完成了 3 次 NMES 测试，以确定诱发全膝关节伸展所需的电流幅度。参与者接受了双侧大腿的磁共振成像（MRI）检查，以测量骨骼肌横截面积（CSA）、大腿皮下脂肪组织（SAT）和肌内脂肪（IMF）。根据确定的电流幅度，将参与者分为高反应者（n = 3）和低反应者（n = 2）。
低反应者完成相同任务所需的电流幅度比高反应者高 48-59%。低反应者的大腿 SAT CSA（51-56%）比 SCI 高反应者大。在调整为整个大腿 CSA 后，低反应者的 IMF CSA 明显更大；而与高反应者相比，骨骼肌 CSA 较低。
这些发现表明，在 SCI 患者接受表面 NMES 应用时，大腿 SAT 和 IMF 起到了阻碍电流传播的绝缘作用。
