Webb Aubrey A, Muir Gillian D
Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, Saskatoon, Saskatchewan, Canada.
J Neurotrauma. 2002 Feb;19(2):239-56. doi: 10.1089/08977150252806983.
The accurate measurement of behavioral compensation after CNS trauma, such as spinal cord injury, is important when assessing the functional effects of injury and treatment in animal models. We investigated the locomotor abilities of rats with unilateral thoracic or cervical spinal cord injuries using a locomotor rating (BBB) scale, reflex tests, and quantitative kinetic measurements. The BBB rating scale indicated that thoracic spinal hemisected (TH) rats had more severely affected hindlimbs compared to cervical spinal hemisected (CH) and sham-operated animals. Kinetic measurements revealed that CH and TH animals moved with different ground reaction force patterns, which nevertheless shared some similarities with each other and with the gait patterns of rats with different unilateral CNS lesions. Uninjured rats typically had an equal distribution of their body weight over the forelimbs and hind limbs, and used their forelimbs predominantly for braking while using their hind limbs mostly for propulsion. CH rats bore more weight on their hind limbs than their forelimbs, while TH animals bore more weight on their forelimbs than their hind limbs. Neither CH nor TH rats used the forelimb ipsilateral to the spinal hemisection for net braking or propulsion. The hindlimb contralateral to the hemisection was placed on the ground prematurely during the stride cycle for both CH and TH animals. The altered kinetics of the locomotor pattern in hemisected animals resulted in changes in the oscillations of total body potential and kinetic energies. These two forms of energy oscillate synchronously in intact locomoting rats, but were asynchronous during parts of the stride cycle in spinal hemisected animals. We conclude that rats develop a general compensatory response for unilateral CNS lesions, which may help stabilize the animal during locomotion.
在评估动物模型中脊髓损伤等中枢神经系统创伤后的功能影响及治疗效果时，准确测量行为补偿情况非常重要。我们使用运动评分（BBB）量表、反射测试和定量动力学测量方法，研究了单侧胸段或颈段脊髓损伤大鼠的运动能力。BBB评分量表显示，与颈段脊髓半横断（CH）和假手术动物相比，胸段脊髓半横断（TH）大鼠的后肢受影响更严重。动力学测量结果表明，CH和TH动物的地面反作用力模式不同，但彼此之间以及与不同单侧中枢神经系统损伤大鼠的步态模式有一些相似之处。未受伤的大鼠通常前肢和后肢均匀分担体重，主要用前肢制动，后肢主要用于推进。CH大鼠后肢承担的体重比前肢多，而TH动物前肢承担的体重比后肢多。CH和TH大鼠都没有使用脊髓半横断同侧的前肢进行净制动或推进。对于CH和TH动物，在步幅周期中，半横断对侧的后肢过早着地。半横断动物运动模式的动力学改变导致全身势能和动能振荡的变化。在完整运动的大鼠中，这两种能量形式同步振荡，但在脊髓半横断动物的步幅周期部分时间内是异步的。我们得出结论，大鼠对单侧中枢神经系统损伤会产生一种普遍的代偿反应，这可能有助于动物在运动过程中保持稳定。
