Applications of Finite Element Methods in Foot and Ankle Biomechanics / 医用生物力学

Finite element method (FEM) has become an effective tool for biomechanical researches because of its high efficiency, accuracy and repeatability. Due to the complex anatomical structure and motion characteristics of foot and ankle, FEM can solve the problems that are difficult to be solved in real experiments with the help of powerful simulation modeling and data calculation ability, which has unique advantages and has been widely used. In this paper, the literatures on foot and ankle biomechanics using FEM at home and abroad in recent five years were summarized, and the following 4 aspects were reviewed: biomechanical analysis of foot and ankle under different motion states, researches on tissue characteristics, clinical treatment analysis, and researches on orthosis and shoes, so as to provide theoretical references for the study of foot and ankle biomechanics, as well as new ideas for the application and development of FEM in the field of foot and ankle biomechanics in the future.

Review on the Progress in Development of Finite Element Models for Functional Spinal Units: Focus on Lumbar and Lumbosacral Levels

@#Functional spinal unit (FSU) has been of major interest in research related to the human spine as it is the simplest entity of spine that is believed to provide vital information useful in analyzing the biomechanics of the spine. In-vitro experiments and in-vivo tests are implemented for this purpose, but due to many restraints in using them, the use of an alternate approach such as Finite Element Analysis (FEA) seems preferential. FEA offers an edge in evaluating significant parameters that may or may not be possible through experiments. The finite element analysis of FSU’s has evolved to handle complexity with the increase in computing capacity and advancement in the software packages. This paper reviews the progress in the development of finite element analysis of FSU’s and also focuses on the application of FEA to analyse the lumbar (L1-L5) and lumbosacral (L5-S1) levels of the spine where spinal disorders are more prevalent.

Study on finite element modeling approach of mandible with full dentition based on CBCT images / 实用口腔医学杂志

Objective: To explore an efficient method for the establishment of 3D finite element model based on CBCT images. Methods: Mandible of a male volunteer was scanned by CBCT, and the resulting DICOM data was used for 3D reconstruction in Mimics17 software. Then with the. stl format file, the result of 3D reconstruction was imported into Geomagic Warp 2015, in which 3D models consisting of triangular patches for dentition, periodontal ligament and alveolar bone were created. With free meshing algorithm, the 3D finite element model of mandible with full dentition consisting of 10-node tetrahedron elements was obtained under the constraint that the maximum inner angle was set to be 25°. Results: The 3D finite element model for human mandible with full dentition was established. The total number of nodes is 299286, the elements number for dentition, periodontal ligament and alveolar bone are105805, 122427 and 577529, respectively. Conclusion: The proposed method can be used for the establishment of 3D finite element model of mandible with full dentition based on CBCT images, and it has the merits of good stability, high precision and wide application compared with the traditional modeling method.

Progress of Finite Element Method Applied in Biomechanical Researches on Lumbar Fusion and Replacement / 医用生物力学

The research progress of finite element method (FEM) applied in biomechanics of lumbar fusion and artificial lumbar disc replacement was reviewed and its prospect was forecasted. The main research directions of FEM are optimal selection of operation plans before the surgery, performance evaluation of implanted devices and prediction of postoperative outcomes. Based on the recent research progress, the application prospects of FEM in simulation of personalized surgery, evaluation of elastic implants and postoperative prediction of novel operation method were discussed. By reviewing and prospecting the application of FEM in biomechanical research of lumbar fusion and artificial lumbar disc replacement, the purpose of this paper is to provide theoretical references and practical guidance for the treatment of lumbar diseases in clinic.

Research progress and application of head finite element model / 医用生物力学

The finite element method (FEM) is a technology for numerical analysis which based on the development of the electronic computer, and also a more advanced biomechanical research method. Early FEM was applied in the fields of engineering science and technology. In recent years, FEM has been widely used for brain research in biomedical engineering. With the rapid development of traffic and transportation, the high incident of craniocerebral injury has become a serious threat to human health year by year. The biomechanical mechanism of craniocerebral injury can be well researched by establishing the finite element model of human head. In this review, establishment, development and application of human head finite element model are summarized, and the future research direction is discussed as well.

Research progress and application of head finite element model / 医用生物力学

The finite element method (FEM) is a technology for numerical analysis which based on the development of the electronic computer,and also a more advanced biomechanical research method.Early FEM was applied in the fields of engineering science and technology.In recent years,FEM has been widely used for brain research in biomedical engineering.With the rapid development of traffic and transportation,the high incident of craniocerebral injury has become a serious threat to human health year by year.The biomechanical mechanism of craniocerebral injury can be well researched by establishing the finite element model of human head.In this review,establishment,development and application of human head finite element model are summarized,and the future research direction is discussed as well.

Three-dimensional finite element analysis of angled abutments in anterior maxilla implant restoration / 西安交通大学学报(医学版)

Objective To explore the effects of angled abutments on the anterior maxilla implant restoration. Methods We analyzed the biomechanical properties of implants of different sizes (Φ3.5 mm,4.0 mm and 4.5 mm in diameter;L11.5 mm and L13 mm in length)after connecting different angled abutments (0°,10°,20°,and 30°) using finite element method.Results The stresses and strains of loading parts of restorations increased and their distribution became more concentrated as the angle of abutment increased.Cortical bone of Φ3 .5 implants with smaller angle (10°or less)andΦ4.0 implants with abutments had the risk of overpassing the bone elastic threshold when the angle approached 30°.However,the cortical bone elastic deformation was within a safe range at all angles inΦ4.5 group.Conclusion We should consider the diameter of the implant when selecting angled abutments.The angled abutments are not suitable for small diameter implants.The bite force should be under control when needed. The larger angled abutments can be applied in the standard and major diameter implants and it is necessary to avoid occlusal overloading.

Finite Element Analysis of Reconstruction of Mandibular Symphysis Defects Using Reconstruction Plates

A Biomechanical Analysis of Surgical Procedures for Osteonecrosis of the Femoral Head using Three-Dimensional Finite Element Method: A Parametrical Analysis by Varying Physiological Loading Conditions / 대한정형외과연구학회지

Many operative procedures for osteonecrosis of the femoral head(ONFH) have been proposed, but their clinical results remain controversial to many clinicians. Recently, a new surgical procedure that incorporates cementation with polymethylmethacrylate(PMMA) after core drilling has been tried clinically. In this study, a finite element method (FEM) was employed to analyze and compare various surgical procedures of ONFH to provide a biomechanical insight by varying physiological loading conditions. Our finite element models were constructed for this purpose they included normal, necrotic, core decompressed, fibular bone grafted, and cementation models. The extent of necrotic region was determined based upon the average CT-scan data from 10 patients. The physiological load directions and magnitudes during the gait cycle were selected at the stage of heel-strike, toe-off, and average stance. The von Mises stresses were calculated and volumetric percentages of the necrotic region under different levels of stresses were analyzed for each model. Our results indicated that there were substantial increase of the necrotic region subjected to the high stress level (beyond 11 MPa) and decrease in the low stress level (below 5 MPa) with the core decompression model, an indication of a malignant stress transfer pattern. On the other hand, the exact opposite pattern of stress transfer was noted with the fibular bone graft and cementation methods suggesting that they could provide structural integrity within the necrotic region.