A Novel Curved Titanium Mesh And Three-dimensional Finite Element Analysis

Objective:This project aims to develop a new type of curved titanium mesh with endplate ring,which contributing to reducing the titanium mesh subsidence that induced by anterior cervical vertebral body subtotal decompression and bone grafting and internal fixation.Also,we explored its mechanical characteristics.Methods:1.On the basis of the structural parameters of normal cervical vertebral and the existing straight titanium mesh,we developed a new type of curved titanium mesh with end plate ring.2.Establishing an effective human cervical vertebral 4 to 6 finite element model by 3D finite element method.3.Implanting a new curved titanium mesh or a traditional straight titanium mesh base on subtotal resection of the fifth cervical vertebral body finite element model.Besides,we compared the stress of titanium mesh,titanium plate and adjacent end plate surfaces of twogroups of models,under five different motion modes.Results:1.We Successfully developed a new type of curved titanium mesh with end plate ring.It consists of a traditional titanium mesh body and two end plate rings.The titanium mesh main body has different radians,and the end plate surface has different angles to adapt to the physiological curvature of the cervical vertebral.In addition,we designed three different specifications(1mm,2mm and 3mm)of the end plate ring to match the decompression grooves of different lengths.2.Establishment of an effective human cervical vertebral 4 to 6finite element model by 3D finite element method.3.Equivalent stress assays for two internal fixations:(1)Under the conditions of side bending,simple compression,extension,forward flexion and rotation load,the equivalent stress of the rear part of the new curved titanium mesh C6 end face is smaller than that of the traditional straight titanium mesh.Also,the equivalent stress of front face of the C6 end plate and the face of the C4 end plate were greater than that of the traditional straight titanium mesh.(2)Under different load conditions,the total equivalent stress of the new curved titanium mesh is smaller than that of the traditional straight titanium mesh.In addition,the equivalent stress mainly concentrated on the end plate ring and the rear of the new curvedtitanium mesh.(3)Under different motion modes,the equivalent stress of the titanium plate in the new curved titanium mesh is greater than that of the traditional straight titanium mesh,and its maximum stress is mainly concentrated on the nail hole area.Conclusions:1.We successfully developed a new type of curved titanium mesh with end plate ring.This new curved titanium mesh with end plate ring is reasonably designed and stress transmission are more in line with the load-bearing structure of the human cervical vertebral.2.Compared with the traditional straight titanium ring mesh with end plate,the new curved titanium ring mesh with end plate can improve the overall stress distribution.Also,it increases the stress distribution of the C4 end plate surface and titanium plate,and reduces the stress distribution of the titanium mesh body.3.The new curved titanium mesh with end plate ring can reduce the stress at the rear of the C6 end plate surface,which may reduce the occurrence of titanium mesh subsidence.