大鼠颈椎骨折错位致脊髓损伤模型的继发性损伤研究

目的　建立大鼠颈椎骨折错位致脊髓继发性损伤模型。 方法　20只成年SD大鼠，随机分为实验组(n=11)和对照组(n=6)，3只处死取颈椎测量C4/5水平椎管和椎体矢状径。实验组利用颈椎骨折错位脊髓损伤装置在C4/5之间快速（200 mm/s）错位1.65 mm，造成颈椎骨折错位和颈脊髓损伤，采用自制器械固定颈椎。对照组除未行错位外与实验组相同。术后进行行为学（前肢运动和梳理试验）评价8周，和病理学检查。 结果 实验组行为学评分各个观察时间点均较对照组低。脊髓HE染色切片见实验组脊髓萎缩，灰质破坏，空洞，对照组未见明显异常。实验组损伤中心残留面积（2.79±0.98）mm2，明显小于对照组（6.36±0.08）mm2（P=0.034）。 结论　成功建立了大鼠颈椎骨折错位脊髓继发性损伤模型，大鼠C4/5骨折错位1.65 mm导致明显的脊髓组织损伤和运动功能障碍。

Secondary spinal cord injury of cervical spine fracturedislocation in rats

Objective To establish a model of secondary SCI of cervical fracture dislocation in rats. Methods 11 male rats were randomly assigned into the cervical fractured islocation group (n=11), the sham group (n=6)。Rats in the experiment group was subjected to fracture dislocation of 1.65 mm at C4/5 at speed of 200 mm/sec, and then stabilized 8 weeks with a custom designed cervical spinal fixation. Behavior was evaluated using the forelimb locomotor and grooming tests. Histology examination was conducted at the lesion epicenter using HE stain. Results The behavior scores of the experiment group were both lower than the sham group. There was rupture of grey mater, cavity in the cord and the cord shrink in the experiment group at 8 weeks after injury. The spared area of the cord at epicenter was (2.79±0.98)mm2 in the experiment group, and lower than the area in the sham group (6.36±0.08) mm2 (P=0.034). Conclusions The present study established the secondary SCI of cervical fracture dislocation in rats. The injury was characterized with the cord damage and locomotor function impair.