Finite Element Analysis Of A Novel Anterior Locking Plate For Unstable Thoracolumbar Burst Fractures

Objective: The finite element analysis method was used to explore the biomechanical stability of a novel locking plate for thoracolumbar burst fracture fusion fixation and its effect on the range of spine motion.Methods: A normal volunteer was selected for a CT scan of the thoracolumbar spine,and a T12-L4 normal 3D spine model(M0)structure was constructed and meshed using software such as Mimics.The meshed 3D model was imported into the finite element software Abaqus to assign material properties to each structure,and the end plates on the T12 vertebral body were subjected to axial 150 N and 10 Nm torque to verify the effectiveness.The verified normal 3D spine model was imported into UG NX software,and three different surgical scheme models were designed: Model A simulated the traditional anterior double-segment fixation instrument,Model B simulated the novel anterior double-segment fixation instrument,and Model C simulated the novel anterior single-segment fixation instrument.Apply an axial pressure of 500 N and a torque of 10 Nm to the end plate on T12,simulate the flexion-extension,lateral bending and rotation movement of each model,and record the maximum stress value of the internal fixation instrument.Results: Among the three simulated surgical fixation models,model A has a larger range of motion in all directions than model B,indicating that the new type of internal fixation can provide greater stability to the spine.Compared with the Model B,the Model C has a larger range of motion in all directions,indicating that the shorter the fixed segment,the better the spine mobility.By comparing the maximum stress of the cage in model A and model B,it is found that the maximum stress of cage in model A is smaller than that in model B except for the extension,indicating that the novel locking plate can play a better supporting effect.When models move in flexion,extension,and left axial rotation directions,the maximum stress value of the internal fixation of the Model A is greater than that of the Model B,indicating that the traditional instrument is liable to form stress concentrations in these movements;the novel locking plate is liable to form stress concentrations in right axial rotation,left lateral bending and right lateral bending directions of movement because of the maximum stress value of the internal fixation of the Model A is smaller than that of the Model B.Conclusions: The novel locking plate has a smaller structure and better performance in biomechanical stability.The novel plate can be used for single-segment fixation,reducing the number of segments that need to be fused,and maintaining maximum spinal motion.However,whether the maximum stress and fatigue effects that can withstand is better than traditional instrument requires further experiments.