关键词: 骨折模型, 大鼠, 闭合性骨折, 开放性骨折

Abstract: Objective The purpose of this study was to comprehensively compare the differences between different method used in previous studies to establish rat fracture models and the stability of the models, and to evaluate the scientific nature and reliability of the improved method for establishing rat osteotomy models, so as to provide a reliable method for establishing animal models for fracture research. Method According to different modeling method, the rats were divided into closed fracture model group and open fracture model group. In the closed fracture model group, the middle femur fracture was established by self-made closed fracture modeling instrument. The weight was 500 g, and the falling height was 22, 26 and 30 cm respectively. In the open fracture model group, transverse or short oblique fractures of the middle femur were made by operation. In the simple Kirschner wire fixation group, different types of Kirschner wires were used for intramedullary fixation. In the Kirschner wire plus wire fixation group, on the basis of intramedullary fixation with Kirschner wire, the two fracture ends were pulled and fixed with absorbable wire. Result In the closed fracture model group, the falling height of weights was 22, 26 and 30 cm, and the success rate was 33%, 50% and 17% respectively. In the open fracture model group, 1. 2 mm Kirschner wire internal fixation was better than 0. 8 and 1. 0 mm Kirschner wire internal fixation. The fracture ends in the Kirschner wire plus thread fixation group were more stable than those in the simple Kirschner wire fixation group. HE staining result showed that the fixation of Kirschner wire plus thread group was stable, the fracture healing was good, and there was no adverse effect of absorbable line on it. Conclusion The open fracture model is easier to control the fracture type and ensure the homogeneity of the experimental objects than the closed fracture model. The fixation effect of Kirschner wire plus thread fixation group is more stable than that of simple Kirschner wire fixation group, which can avoid nonunion or delayed union of fracture due to unstable fixation of fracture ends,Resulting in sample shedding and deviation of experimental result due to loose fixation, which ensures the homogeneity of experimental objects and reduces random error.

Key words: fracture model, rats, closed fracture, open fracture