Ballermann Mark, Tse Arthur D Y, Misiaszek John E, Fouad Karim
Centre for Neuroscience, University of Alberta, Edmonton, Alberta, Canada.
J Neurotrauma. 2006 Jun;23(6):897-907. doi: 10.1089/neu.2006.23.897.
Walking ability is a measure of recovery used in many studies that test experimental strategies to treat injuries or diseases of the central nervous system (CNS) in animal models. A common measure in the rat animal model of thoracic spinal cord injury (SCI) is visual inspection and scoring of hind limb activity, which allows the documentation of movements associated with the recovery of locomotor function. In this study, we expand on previously documented visible changes in the locomotor pattern following SCI. The spontaneous recovery of locomotion in rats with thoracic SCIs of variable extent was evaluated using electromyographic (EMG) and kinematic analysis while rats walked on an elevated runway. Comparisons with pre-lesion walking sequences revealed changes in the kinematics and in the muscle activation pattern of various muscles, including enhanced fore limb extensor activity, possibly reflecting an increased contribution to propulsion, altered recruitment of back muscles inserting into the hip (possibly to support stepping movements), and elevated posture during stance, which may compensate for deficits in weight support. These changes were noted in spinal cord injured rats with varying degrees of impairment, including animals with no visually detectable deficit in open-field walking. In summary, the presented results demonstrate that spinal cord injured rats develop alternative locomotor patterns following SCI that cannot be discriminated by the use of qualitative visually based analysis, thus urging the use of quantitative outcome measures in assessing motor function after SCI.
行走能力是许多研究中用于衡量恢复情况的指标，这些研究测试了在动物模型中治疗中枢神经系统（CNS）损伤或疾病的实验策略。在大鼠胸段脊髓损伤（SCI）动物模型中，一种常用的测量方法是对后肢活动进行视觉检查和评分，这可以记录与运动功能恢复相关的运动。在本研究中，我们扩展了先前记录的SCI后运动模式的可见变化。在大鼠在高架跑道上行走时，使用肌电图（EMG）和运动学分析评估了不同程度胸段SCI大鼠的自发运动恢复情况。与损伤前行走序列的比较揭示了各种肌肉的运动学和肌肉激活模式的变化，包括前肢伸肌活动增强，这可能反映了对推进的贡献增加，插入髋部的背部肌肉募集改变（可能是为了支持步行动作），以及站立时姿势升高，这可能补偿了体重支撑方面的缺陷。在不同程度损伤的脊髓损伤大鼠中都观察到了这些变化，包括在旷场行走中没有视觉上可检测到缺陷的动物。总之，所呈现的结果表明，脊髓损伤大鼠在SCI后会形成替代的运动模式，而使用基于视觉的定性分析无法区分这些模式，因此迫切需要在评估SCI后的运动功能时使用定量结果测量方法。
