Jurkiewicz Michael T, Mikulis David J, McIlroy William E, Fehlings Michael G, Verrier Mary C
Department of Physiology, University of Toronto, Toronto, Canada.
Neurorehabil Neural Repair. 2007 Nov-Dec;21(6):527-38. doi: 10.1177/1545968307301872. Epub 2007 May 16.
Although the consequences of spinal cord injury (SCI) within the spinal cord and peripheral nervous system have been studied extensively, the influence of SCI on supraspinal structures during recovery remains largely unexplored.
To assess temporal changes in cortical sensorimotor representations beginning in the subacute phase following SCI and determine if an association exists between the plastic changes within cortical sensorimotor areas and recovery of movement postinjury.
Functional magnetic resonance imaging (fMRI) was used to study 6 SCI patients for 1 year, beginning shortly postinjury, and 10 healthy control individuals. During fMRI, individuals performed a simple self-paced wrist extension motor task. Recovery of movement was assessed using the American Spinal Injury Association (ASIA) Standard Neurological Classification of SCI.
In the subacute period post-SCI, during impaired movement, little task-related activation within the primary motor cortex (M1) was present, whereas activation in associated cortical sensorimotor areas was more extensive than in controls. During motor recovery, a progressive enlargement in the volume of movement-related M1 activation and decreased activation in associated cortical sensorimotor areas was seen. When movement was performed with little to no impairment, the overall pattern of cortical activation was similar to that observed in control individuals.
This study provides the first report of the temporal progression of cortical sensorimotor representational plasticity during recovery following traumatic SCI in humans and suggests an association between movement-related fMRI activation and motor recovery postinjury. These findings have implications on current and future rehabilitative interventions for patients with SCI.
尽管脊髓损伤（SCI）对脊髓和周围神经系统的影响已得到广泛研究，但SCI在恢复过程中对脊髓上结构的影响仍未得到充分探索。
评估SCI亚急性期开始后皮质感觉运动表征的时间变化，并确定皮质感觉运动区域内的可塑性变化与损伤后运动恢复之间是否存在关联。
采用功能磁共振成像（fMRI）对6例SCI患者进行为期1年的研究，研究从损伤后不久开始，并纳入10名健康对照个体。在fMRI期间，个体执行简单的自定节奏的腕部伸展运动任务。使用美国脊髓损伤协会（ASIA）脊髓损伤神经学分类标准评估运动恢复情况。
在SCI后的亚急性期，运动受损时，初级运动皮层（M1）内几乎没有与任务相关的激活，而相关皮质感觉运动区域的激活比对照组更广泛。在运动恢复过程中，与运动相关的M1激活体积逐渐增大，相关皮质感觉运动区域的激活减少。当运动几乎没有或没有损伤时，皮质激活的总体模式与对照组相似。
本研究首次报告了人类创伤性SCI后恢复过程中皮质感觉运动表征可塑性的时间进程，并表明与运动相关的fMRI激活与损伤后运动恢复之间存在关联。这些发现对当前和未来SCI患者的康复干预具有启示意义。
