Abstract：【Objective】 To established mild, moderate and severe models of spinal cord injury with a MASCIS impactor.【Methods】 In female adult SpragueDawley rats, T10 spinous process and the corresponding vertebral lamina were removed and spinal cord endorhachis was exposed. Three levels of injury were inflicted to rat spinal cord by dropping a 10g rod 12.5, 25.0 or 50.0 mm on to exposed spinal cord. The control group underwent T10~11 laminectomies alone. The behavioral scores and pathological alterations were recorded at different timepoints. 【Results】 In control group, the rats could walk after reviving and the microstructure of spinal cord was normal. Group A (12.5 mm), 1 month after operation, movement function was almost restored, the score of Basso, Beattie & Bresnahan (BBB) was 17.34±1.00, microstructure of spinal cord was distinct, glial cell hyperplasia; group B (25 mm), 1 month after operation, the score of BBB was 7.32±1.12, lacunar formation, glial cell hyperplasia and several variant neurons were present in microstructure of spinal cord; group C (50 mm), 1 month after operation, the score of BBB was 4.87±0.31, residue spinal cord tissues were less abundant than group B. The spinal cord structure was disorderly and seriously deformed. The necrotic cavity accounted for about 80% of spinal cord. The grading differences were statistically significant between groups A, B and C and normal control (P<0.05）. 【Conclusion】 The models of three levels of mild, moderate and severe injury made by a MASCIS impactor are stable, reliable and reproducible. they can used for elucidating the mechanism of spinal cord injury, pathophysiological changes and different treatments.
2015, Vol. 32 
