Reverse Engineering Research And Finite Element Analysis Of Children Femur-Proximal Based On CT Data

This article has studied a way based on the CT data, the DICOM standard and the Mimics software which realizes three dimensional reconstruction of the human bone. This work has narrated the whole idea and specific process of the three dimensional medicinal reconstruction in detail and reappeard Femur-Proximal and hip of a DDH child as well as the complex shape of normal child's Femur-Proximal. The created model which is particular verisimilitude and nice reducibility might be revolved at random, so that you can observe from different angles. The whole idea and the specific process of in detail.The course of establishing three-dimensional finite element model handling with the software Mimics and Ansys comes down to a problem about lead-in and lead-out of the data which is solved by programming using the ADPL of Ansys. Thus, it establishes the foundation for doing the research about this aspect more. The work particularly narrates the finite element model of children Femur-Proximal as well as the course of distributing material property to the finite element model of children Femur-Proximal, define material characteristic parameter on the base of the experience relation among CT value, Apparent density and the Young's modulus E. The way of Femur-Proximal three-dimensional finite element model on the base of CT has the following advantages:1 It can take full advantage of the geometry modality and material characteristic information about Femur-Proximal supplied by CT data. Compared with the old way, it can establish Femur-Proximal three-dimensional finite element model more accurately in order to assure the accuracy of finite element analysis result.2 The material characteristic setting of this way can manifest the non-uniformity of skeleton material more precisly than the old way which distributes single material.Besides. This way can shorten modeling time because there is no need to confirm the interface among compact bone, spongy bone and marrow. This study through the finite element analysis of normal children and DDH children Femur-Proximal, research results show that:(1) In the same load, the Femur-Proximal of DDH children is easiest to have the deformation. Therefore, the DDH children should try to avoid a great load, in order to prevent the occurrence of fractures;(2) The stress level is high in the outside and inside of the chileren Femur-Proximal, particularly, the medial femoral neck equivalent to the femur from the site. The part with the thick bong and the higher density, which can withstand the high stress caused by the weight of the upper body and avoids fatigue fracture. Such this kind of stress and the bone density distribution method are consistent with the basic principles of mechanics, which is another corroboration of Wolff law. In once more, it manifests the each kind of organizational structure and the function uniformity of human body;(3) The strain is consistent with the stress. According to the femoral neck stress cloud, the high levels of stress positions can be seen. When the femur receive the violence, the most vulnerable to fractures is the femoral neck for the position. In physical exercise and fracture after treatment the protection of these sections should focused.In brief, this article makes a comparative analysis of Femur-Proximal biomechanical characteristics when the DDH child and the normal child stand with legs and the single leg and simulate adding different conditions to Femur-Proximal. The results of this study can effectively evaluate development of DDH children Femur-Proximal and forecast the femur possible changes in development. Three-dimensional finite element analysis is a kind of convenient and practicable method to research biomechanics of human being, in addition, can be used as the confirmation and supplement of experiment biomechanics study.