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BACKGROUND:The hip is a complicated structure and irregular in shape. It is hard to measure stress distribution and transmission. OBJECTIVE:To establish a three-dimensional finite element model of the hip joint and upper femur, and analyze the stress distribution and transmission characteristics of the acetabulum region under different loads, and explore mechanics mechanism of hip fracture based on CT data. METHODS:The three-dimensional finite element hip and femur model were reconstructed in Mimics 14.0 based on the CT data of a healthy adult man. After dividing mesh, assigning material and transforming into finite element model, the stress distributions of anterior wal , the top, and the posterior wal of the acetabulum, the stress of acetabulum areas and displacement of acetabular unit were calculated with finite element software Ansys 13.0 software under 300, 600, 900 and 1 200 N. RESULTS AND CONCLUSION:(1) A three-dimensional finite element model of the hip and the femur was successful y established, consisting of 284 183 nodes and 160 665 units. (2) The characteristics of the stress distribution of acetabulum region:the maximal stress was concentrated on the posterosuperior part of acetabular crest, fol owed by the posterior wal and the anterior wal in order in upright position under different loads. The stress transmitted by four ways:from acetabular crest to ilium, along linea terminalis of pelvis to sacroiliac joint, in the acetabular sockets, and along the pubic ramus. The stress and the propagation distance were increasing as the loads increased. Acetabular element stress variable was increased. (3) Above results indicated that three-dimensional finite element model of the human hip joint established by Mimics 14.0 based on CT data matches the anatomical structure in a great degree, could be used in the biomechanics analysis under different loads, and has a guiding significance for design of artificial hip prosthesis.
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BACKGROUND:Recently, studies on three-dimensional reconstruction and biomechanics became more and more. Three-dimensional models of organs were established by modeling software based on image data using computer. Mechanical analysis was conducted using finite element analysis software. After literature retrieval, we found that the principle of three-dimensional reconstruction of human organs is not clear, and the process description is relatively simple. Some is not accorded with the fact. Above studies cannot guide related research. OBJECTIVE:To explore the principle, process, results and further application of three-dimensional reconstruction models of organs, and to provide evidence for future studies. METHODS:We retrieved China National Knowledge Infrastructure for representative literatures about three-dimensional reconstruction of human organs using the computer, and analyzed the principle, process, results and further application of three-dimensional reconstruction models of organs. RESULTS AND CONCLUSION:In combination with established three-dimensional bone models, we explained the principle, process, and application of three-dimensional reconstruction in detail, and laid the theoretical foundation for subsequent biomechanical research. With continuous development of tissue engineering technology, scholars have begun to study the pathogenesis of bone injury from various angles and different aspects so as to better prevent and treat this disease. The related research is stil in its primary stage, and stil needs further investigations.
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BACKGROUND:In recent years, increasing research emphasizes the puncture position of the foramen ovale in skul , but most of the positin methods require a higher personal experience of surgeons and lack of individualized quantitative parameters. OBJECTIVE:To establish a visualized digital model of the foramen ovale in skul , explore the reasonable puncture path and puncture depth of percutaneous treatment of foramen ovale puncture for trigeminal neuralgia, and develop the individualized treatment of trigeminal neuralgia. METHODS:Head CT images from healthy adult male volunteers were obtained and were input into three-dimensional reconstruction software MIMICS 10.01, the three-dimensional visualized models of the skul and skin were established. Using the models, the puncture path of the foramen ovale was designed and the preliminary model of the puncture locator was plotted. RESULTS AND CONCLUSION:The three-dimensional visualized digital model of the foramen ovale puncture path was established with CT scan images by using MIMICS software, which provides reliable anatomical data for clinical teaching and lays the groundwork for the simulation of puncture surgery. On the three-dimensional models, the“needle points”,“target points”, and“midpoint”were determined, and the triangle consisted of the three points was regarded as“positioning plane”. Using these parameters, the positioning instrument is characterized by simple structure, convenient operation, high positioning precision and short period of exposure to radiation, it simulates the foramen ovale puncture needle depth and needle direction in a precise and individualized manner.
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BACKGROUND:Recently, scholars al over the world have made numerous studies on three-dimensional visualization model of reconstructing maxil ofacial bone tissue, skin, and muscle in the ordinary PC. However, few studies concerned the three-dimensional visualization model of constructing maxil ofacial bone tissue, skin, muscle and blood vessels. OBJECTIVE:To establish a three-dimensional visualization model of the complete maxil ofacial region using an ordinary PC based on spiral CT, MRI data, and three-dimensional reconstruction software. METHODS:One healthy male adult was chosen as the object in this study. CT and MRI were performed respectively to acquire the DICOM standardized image of the sample. Al CT and MRI images were imported to Mimics to construct three-dimensional visualization models of the bones in the maxil ofacial region, some masseter muscles, trigeminal cistern, internal carotid artery and internal jugular vein. Three-dimensional model of the bones in the maxil ofacial region was chosen as the reference. Models of muscles, blood vessels and trigeminal cistern established by MRI images were imported, and registration in space of three-dimensional model was performed. At last, three-dimensional visualization model of the complete maxil ofacial region was acquired. RESULTS AND CONCLUSION:The integrated three-dimensional models of the bones, muscles, skin, trigeminal cistern and blood vessels in the maxil ofacial region established accurately reflected the complex anatomic structure of maxil ofacial region, provided reliable anatomic data for clinical diagnosis and laid a good foundation for sham operations in the future.