Biomechanical Study On Internal And External Fixation Of Femoral Fractures

The femur is one of the main weight-bearing bones in the human body.Bone trauma causes great pain both physically and mentally.The surgical treatment of femoral fracture includes external fixation and internal fixation.At present,whether external fixator treatment or internal fixation treatment is selected,doctors decide some parameters according to clinical experience,such as the type of bone plate,the number and distribution of screws,the type of screws,as well as the location of external fixator installation,the number and distribution of Shancz nail fixation,etc..If the treatment method is not reasonable,it will lead to fracture of the bone plate,loosening,Shancz nail infection of the external fixator and other physical failure.Therefore,in this paper,the biomechanical characteristics of femoral fracture treatment methods were studied by using computer-aided design technology,reverse engineering technology and finite element analysis technology.The biomechanical characteristics of interlocking and anatomic bone plates for fixation of femoral shaft fractures were studied.Using the patient's femur CT scan data,the 3d CAD model of femur was obtained by editing and 3d reconstruction in Mimics software.Three-dimensional CAD model of bone plate was established by reverse engineering.The types,number and distribution of screws of bone plate for femoral shaft fracture were studied.The results showed that the deformation and stress of anatomic bone grafting plate were less than that of straight bone grafting plate,the deformation and stress of straight bone grafting plate were less than that of straight bone grafting plate,and the deformation and stress of plastic bone grafting plate were less than that of straight bone grafting plate.The biomechanical characteristics of femoral shaft fractures fixed with external fixator were studied,and the influence rules of the distance between fracture fracture and the nearest Shancz nail,the distance between external fixator and femur,and the number of bone needles were analyzed.It indicates that the closer the distance between the femur and the external fixator,the smaller the deformation and stress of the external fixator system will be.The distance between the fracture fracture and the nearest fracture fracture Shancz nail had no significant effect on the femoral-external fixation system,while the number of Shancz nail had a significant effect on the femoral-external fixation system.Install 6 Shancz nails with less deformation and stress than 4 Shancz nails.The first Shancz nail has the greatest potential for fatigue damage.The biomechanical properties of Proximal Femoral Nail Anturotation-PFNA and external fixation were studied.The effect of deformation and stress distribution of Shancz nails on femoral-external fixation system was analyzed.The effects of deformation and stress distribution on the femoral-PFNA system were analyzed.To compare the mechanical properties of external fixator and PFNA in the treatment of intertrochanteric fractures.Show that two kinds of treatment for intertrochanteric fractures in PFNA treatment stress is less than the external fixator of intertrochanteric-external fixation treatment,first Shancz nail stress,the largest Shancz screw loosening or the possibility of failure than other Shancz screw loosening or the possibility of failure,PFNA intertrochanteric fracture treatment,the stress of the locking nail,the largest of intertrochanteric-PFNA very important role in the system.