Blight A
Center for Paralysis Research School of Veterinary Medicine Purdue University, West LaFayette, IN.
J Am Paraplegia Soc. 1988 Jul-Oct;11(2):26-34. doi: 10.1080/01952307.1988.11735792.
Reliable animal models of spinal cord injury are essential for studying pathological mechanisms and for laboratory testing of experimental treatments. The normal unpredictability of neurological outcome following experimental injury results partly from variations in the mechanics of both apparatus and tissue. Weight drop contusion models have been used extensively, and often effectively within a given study, but direct comparison between studies is usually made impossible by differences in the experimental parameters. The most important differences include the weight-height combination, the mass of the interface between weight and cord, and the support given to the cord from below. There are also important dimensional and physiological variables intrinsic to the biological material, which are usually ignored. A morphometric study of contusion injuries of the cat thoracic cord indicates that the major determinant of axon disruption is the extrusion of tissue from the impact site, due to viscoelastic distortion of the parenchyma within the meningeal tube. Direct compression and shear do not appear to play an important role in this kind of injury, where a brief compression of the cord occurs at an initial velocity of about 1.5 m/sec. The pathology produced by slower compression rates may vary, but the pattern of central necrosis, expected to be produced by extrusion, is common to most types of experimental lesion and to a large proportion of human injuries.
可靠的脊髓损伤动物模型对于研究病理机制和实验性治疗的实验室测试至关重要。实验性损伤后神经学结果的正常不可预测性部分源于仪器和组织力学的变化。重物坠落挫伤模型已被广泛使用，并且在给定的研究中常常有效，但由于实验参数的差异，通常无法在不同研究之间进行直接比较。最重要的差异包括重量-高度组合、重物与脊髓之间界面的质量以及下方对脊髓的支撑。生物材料本身还存在重要的尺寸和生理变量，这些通常被忽略。一项对猫胸段脊髓挫伤损伤的形态计量学研究表明，轴突中断的主要决定因素是由于脑膜管内实质的粘弹性变形导致组织从撞击部位挤出。在这种损伤中，直接压缩和剪切似乎并不起重要作用，在这种损伤中，脊髓会以约1.5米/秒的初始速度发生短暂压缩。较慢压缩速率产生的病理变化可能不同，但预期由挤出产生的中央坏死模式在大多数类型的实验性病变和很大比例的人类损伤中是常见的。
