Research On Material Parameterization Of 3-12 Year Old Children's Cervical Spine

Traffic accidents are an important factor causing child casualties,and cervical spine injury is a common form of injury for children in accidents,with Characteristics of high morbidity and high mortality.Because children's cadaveric experimental data sources are limited,there is less research on children's cervical spine injury.Although some children's cervical spine finite element models have been developed to study the mechanism of child injury,these models are developed for specific ages and can't be used well to study the difference in the injury of children of different ages.Children are in the stage of growth and development,the mechanical characteristics of cervical tissue changes greatly with age.The study of children's cervical tissue material characteristics with the change of age has important reference value for the development of children's cervical spine finite element model and the research of children's injury mechanism.Due to the limitation of conditions,it is not realistic to use the method of corpse experiment to obtain the material parameters of the tissue.Therefore,this article will be based on the experimental data of human tissue from other scholars.Firstly,through a large number of literature research work,this article summarized the study on the mechanical properties of the domestic and foreign scholars on the human cervical spine,and analyzed the results of these studies,obtained the material parameters of adult cervical tissue.Then based on the human cervical material parameters acquisition method,the cervical spine material parameters of children were established by the methods of scaling adult cervical material parameters and related mechanical property curve.Finally,the parameterization methods for vertebral,ligament,intervertebral discs and other tissue materials were introduced.The parameterization results of cervical on the material parameters of each tissue with the change of age were summarized.Based on the established parametric material model,three C4-C5 cervical segment models of age-representative children were selected for simulation analysis of dynamic tension,flexion-extension,lateral bending,axial rotation and other load conditions.The experimental data of the existing corpses of Luck,Yoganandan,and Nightingale were scaled according to Irwin's neck-response scaling method,and the response data of children of different ages were obtained.According to the error between the simulation results and the children's response data,the sensitive tissues that have a greater influence on the mechanical response of the cervical spine were analyzed to determine the material parameters that have a significant influence on the mechanical response of the cervical spine in the sensitive tissue.Finally,the sensitive parameters were performed optimization through an adaptive response surface method,and regression analysis of the optimized parameters.Children's cervical vertebrae,articular surface angles and intervertebral disc anatomical structures and mechanical characteristics during the growth and development were introduced,and the relationship between the changes in anatomical structure and mechanical response of children's cervical spine and the trends of changes in vertebral mineral content during the growth of children and the relationship between mechanical properties of the vertebrae and changes in their material parameters were analyzed.Next,several sets of simulation models were established using the established parameterized material model to investigate the effect of changes in material parameters on the children's cervical spine mechanical response,and combined with simulation results to analyze the differences in children's cervical spine injury.