Kim Yongchul, Youm Youngil, Wu Ming, Schmit Brian D
Department of Mechanical Engineering, Pohang University of Science and Technology, San 31, Hyoja-dong, Nam-gu, Pohang City, Kyungbuk 790-784, South Korea.
J Clin Neurosci. 2007 Nov;14(11):1078-88. doi: 10.1016/j.jocn.2006.06.021. Epub 2007 Aug 24.
The aim of this study was to investigate the influence of hip proprioceptors on the organisation of the flexor reflex elicited by nociceptive stimulation in individuals with spinal cord injury. The influence of hip position and passive movement were tested in 10 subjects with chronic spinal cord injury. Stimuli were tested isometrically with the hip in three positions. Additionally, the response was also measured to stimuli applied with the hip at midposition during imposed hip flexion and extension movement. The torque and EMG responses were compared in order to identify the postural and movement-dependent modulation of the withdrawal reflex. Ankle and hip torques were significantly modulated by hip position (ANOVA, p<0.05), with the largest torque response obtained in the hip extended position, compared with the flexed position. We also observed a significant difference between the flexor reflex during movement and with the leg isometric. Ankle and hip torque and tibialis anterior electromyograms were significantly higher in the movement conditions than the isometric condition (Tukey test, p<0.05). We postulate that inputs from hip proprioceptors enhance the withdrawal reflex response. Movement appears to increase the response, regardless of movement direction, suggesting a novel role for the dynamic components of hip afferents.
本研究的目的是探讨髋部本体感受器对脊髓损伤个体中伤害性刺激引发的屈肌反射组织的影响。在10名慢性脊髓损伤受试者中测试了髋部位置和被动运动的影响。在髋部的三个位置等长测试刺激。此外，还测量了在髋部屈伸运动期间髋部处于中位时施加刺激的反应。比较了扭矩和肌电图反应，以确定撤离反射的姿势和运动依赖性调制。髋部位置对踝关节和髋部扭矩有显著调制作用（方差分析，p<0.05），与屈曲位置相比，在髋部伸展位置获得的扭矩反应最大。我们还观察到运动期间的屈肌反射与腿部等长时的屈肌反射之间存在显著差异。运动条件下的踝关节和髋部扭矩以及胫骨前肌肌电图显著高于等长条件（Tukey检验，p<0.05）。我们推测髋部本体感受器的输入增强了撤离反射反应。无论运动方向如何，运动似乎都会增加反应，这表明髋部传入神经的动态成分具有新的作用。
