[A model of mild spinal cord injury in rats--dynamics of changes in motor function]

Authors proceeded by performing compressive spinal traumas of variable intensity in 21 rats at lower thoracic level over an intact dura. The deficit of hind limbs motor functions was evaluated simultaneously with the two tests as follows: a) in observing the gait of an animal along with graduation in accord with modified Tarlov's classification, b) with the method of inclined plane. The reproducibility of injuries of various intensity appeared to be imperfect. Five animals with severe injury died up to 4 weeks (Fig. 4, 5). The remainder of them showed substantial approval (mild injury--Fig. 6-13). The dynamics of motor disorder showed changes up to 6 weeks, after then the state persisted unchanged up to 2 months. Within this survival interval, rats were killed either in the state of mild paresis or even under regained normal condition. It outflowed from our study that a long term monitoring of postinjury spinal cord function is important in order not to ascribe possible approval of the functions to the therapy applied. Further on course of disorder can be predicted in accordance with duration of initial paraplegia. The post-surgery paraplegia had lasted for only several hours in the animals whose injuries resulted in a normal condition.