关键词: 大鼠, 胫骨骨折, 动物模型, 骨折愈合, Micro-CT

Abstract: Objective To establish a model of tibial bone defect in rats prepared by Kirschner wire cortical fixation method, and to evaluate it by imaging. Method A total of 30 ( Sprague-Dawley, SD) rats were divided into three groups: sham group, fixed group and unfixed group, with 10 rats in each group, the fixed group and the non-fixed group had bone defects caused by chainsaws in the middle of the tibia, the width of the defect was 2 mm, the depth was 2 mm, the fixed group was fixed in the bone cortex with K-wire ( the non-fixed group did not use K-wire ) , and the sham group only exposed the middle tibia. Micro computed tomography ( Micro-CT) , Hematoxylin-eosin staining ( HE staining ) , Masson’ s trichrome staining, Safranin O / Fast green staining, Toluidine blue staining was used to evaluate the bone defect model and healing. Result The success rate of modeling in the fixed group was 100% and 60% in the unfixed group on the 3rd day after surgery (P<0. 05) . The height and width of the bone defect were (1. 65±0. 21) mm and ( 1. 99±0. 15) mm measured by Micro-CT on the 3 days after operation, and the width and height of the bone defect were ( 1. 38±0. 17) mm and ( 1. 77±0. 16) mm on the 14 days after surgery. Micro-CT result were consistent with tissue sectioning result. Conclusion In this study, the K-wire cortical fixation method was used to prepare the defect model, and the morphology and healing of the model can be evaluated by Micro-CT, which provides an animal model for the basic research on the diagnosis and treatment of bone defect.

Key words: rat, tibial fracture, animal models, fracture healing, micro-CT