Development of a method for experimental modeling of tubular bone fractures in rats

Today in orthopedics and traumatology there are many ways to model different types of bone fractures, which have different modifications based on the need to model a particular clinical situation. In our study, we set out to develop and select the optimal model of tubular bone fracture in rats for its intramedullary fixation with pivots from different types of implants. The study was performed in two stages: at the first stage, the femur of 24 mature Wistar rats was examined and a complete transverse diaphyseal fracture of the left femur was modeled by surgical intervention, followed by retrograde intramedullary osteosynthesis. The second stage was performed on 24 mature Wistar rats with modeling of incomplete transverse fracture of the left tibia and antegrade insertion of the implant into the bone marrow cavity through a separate hole in the bone. All animals underwent radiological control. Bones were removed on days 7 and 30 after surgery. Histological preparations were made according to standard methods. Regeneration was assessed by observation microscopy with hematoxylin and eosin staining. The results of X-ray and microscopic studies showed that in animals with a model of complete transverse fracture, a significant difference in the ends of bone fragments was determined, which affected the stages of regenerate formation. These shortcomings were leveled in our proposed model of incomplete transverse fracture and also allowed us to form a control group.