Modulation of coordinated muscle activity during imposed sinusoidal hip movements in human spinal cord injury.
Modulation of coordinated muscle activity during imposed sinusoidal hip movements in human spinal cord injury.
复制标题
在人类脊髓损伤中施加正弦髋关节运动期间协调肌肉活动的调节。
DOI：
10.1152/jn.00677.2003
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
Schmit,BrianD
中科院分区：
文献类型：
--
作者：
Steldt,RobertE;Schmit,BrianD
慢性脊髓损伤（SCI）患者常表现出多关节反射活动，临床上被归类为伸肌痉挛。这些反应通常与髋关节的强制伸展运动结合观察到，例如从坐姿到仰卧位的运动。巧合的是，髋关节本体感受器的传入反馈也有牵连的运动控制的脊髓化猫。由于这种并发症，我们推测，伸肌痉挛，髋关节伸展触发可能涉及激活有组织的神经元间回路，也有运动的作用。如果这是真的，那么髋关节的强制性振荡将预期产生运动模式中的腿部肌肉组织的活动。此外，这种肌肉活动将被夹带到臀部运动。10名慢性SCI患者的右髋关节，包括完全性[美国脊柱损伤协会（ASIA）A]和不完全性（ASIA B，C）损伤，使用定制的髋关节系统在40 °至-15°（±5°）的范围内以60°/s的速度进行斜坡和保持（10 s）运动，并以1.2、1.88和2.2 rad/s的速度进行正弦振荡。记录下肢七块肌肉的表面肌电图和矢状面关节力矩以表征反应。斜升和保持扰动在髋关节、膝关节和踝关节产生共激活，持续时间长（5-10 s）。正弦扰动产生一致的肌肉时序模式，导致交替屈肌和伸肌关节扭矩。肌电图和关节扭矩通常夹带的运动频率，股直肌，股内侧肌，比目鱼肌活动与髋关节伸展和内侧腘绳肌活动发生在髋关节屈曲。除了股内侧肌外，个体肌肉的时间模式与正常步态中的髋关节位置一致。这些结果表明，与伸肌痉挛相关的反射可能通过有组织的神经元间通路发生，如运动的脊髓中心。
Individuals with chronic spinal cord injury (SCI) often demonstrate multijoint reflex activity that is clinically classified as an extensor spasm. These responses are commonly observed in conjunction with an imposed extension movement of the hips, such as movement from a sit to a supine position. Coincidentally, afferent feedback from hip proprioceptors has also been implicated in the control of locomotion in the spinalized cat. Because of this concurrence, we postulated that extensor spasms that are triggered by hip extension might involve activation of organized interneuronal circuits that also have a role in locomotion. If true, imposed oscillations of the hip would be expected to produce activity of the leg musculature in a locomotor pattern. Furthermore, this muscle activity would be entrained to the hip movement. The right hip joints of 10 individuals with chronic SCI, consisting of both complete [American Spinal Injury Association (ASIA) A] and incomplete (ASIA B,C) injuries, were subjected to ramp and hold (10 s) movements at 60°/s and sinusoidal oscillations at 1.2, 1.88, and 2.2 rad/s over ranges from 40 to –15° (±5°) using a custom servomotor system. Surface EMG from seven lower extremity muscles and sagittal-plane joint torques were recorded to characterize the response. Ramp and hold perturbations produced coactivation at the hip, knee, and ankle joints, with a long duration (5–10 s). Sinusoidal perturbations yielded consistent muscle timing patterns that resulted in alternating flexor and extensor joint torques. EMG and joint torques were commonly entrained to the frequency of movement, with rectus femoris, vastus medialis, and soleus activity coinciding with hip extension and medial hamstrings activity occurring during hip flexion. Individual muscle timing patterns were consistent with hip position during normal gait, except for the vastus medialis. These results suggest that reflexes associated with extensor spasms may occur through organized interneuronal pathways, such as spinal centers for locomotion.