With the development of economy and the progress of medical science and technology,artificial prosthesis replacement has become an important means to improve the dysfunction caused by human bone diseases.However,there...With the development of economy and the progress of medical science and technology,artificial prosthesis replacement has become an important means to improve the dysfunction caused by human bone diseases.However,there are still some loose phenomena caused by stress shielding.To solve the complications of aseptic loosening after calcaneal prosthesis replacement,an optimal design method for the prosthesis was proposed.The prosthesis was designed and optimized according to the real bone shape and the replacement requirements by the combination of computed tomography(CT)technology,computer-aided design,finite element analysis,and power flow theory.CT data were imported into MIMICS and Geomagic Studios.UG was used to obtain the geometric model of the human skeleton.Then,the 3D finite element model of the prosthesis was established by combining the finite element software Abaqus,and a series of finite element analysis was carried out.The prosthesis was topologically optimized and filled with a porous structure.The prosthesis was implanted by computer simulation.Finally,the power flow method was used to compare the dynamic performance and energy transfer before and after the prosthesis replacement to verify the rationality of the prosthesis design.In this paper,this method was used to optimize the design of the calcaneal prosthesis,and the research shows that this method can reduce the stress shielding effect of the calcaneal prosthesis.From the case of calcaneal prosthesis optimization,this method is not only a supplement to the contemporary biomechanical theory but also can guide the design of bone prosthesis in bone prosthesis replacement surgery.展开更多
During the modern city construction,the conservation of the historic buildings is especial important,for the future development is based on the historic accumulation.Timber element,which is the common material in the ...During the modern city construction,the conservation of the historic buildings is especial important,for the future development is based on the historic accumulation.Timber element,which is the common material in the historic buildings,always sufferd by the varies natural or man-made factors,and finally lead to huge threaten to the entire structure.The conservation methods often changing according to the different circumstances and degree of destruction.This paper has introduced two approaches,repair and replacement,compared the advantages and disadvantages of each,and then summary the application of two methods in the light of conservation principle.展开更多
Background Dislocation is the second most common complication of hip replacement surgery, and impact of the prosthesis is believed to be the fundamental reason. The present study employed Solidworks 2003 and MSC-Nastr...Background Dislocation is the second most common complication of hip replacement surgery, and impact of the prosthesis is believed to be the fundamental reason. The present study employed Solidworks 2003 and MSC-Nastran software to analyze the three dimensional variables in order to investigate how to prevent dislocation following hip replacement surgery. Methods Computed tomography （CT） imaging was used to collect femoral outline data and Solidworks 2003 software was used to construct the cup model with variabilities. Nastran software was used to evaluate dislocation at different prosthesis positions and different geometrical shapes. Three dimensional movement and results from finite element method were analyzed and the values of dislocation resistance index （DRI）, range of motion to impingement （ROM-I）, range of motion to dislocation （ROM-D） and peak resisting moment （PRM） were determined. Computer simulation was used to evaluate the range of motion of the hip joint at different prosthesis positions. Results Finite element analysis showed： （1） Increasing the ratio of head/neck increased the ROM-I values and moderately increased ROM-D and PRM values. Increasing the head size significantly increased PRM and to some extent ROM-I and ROM-D values, which suggested that there would be a greater likelihood of dislocation. （2） Increasing the anteversion angle increased the ROM-I, ROM-D, PRM, energy required for dislocation （ENERGY-D） and DRI values, which would increase the stability of the joint. （3） As the chamber angle was increased, ROM-I, ROM-D, PRM, Energy-D and DRI values were increased, resulting in improved joint stability. Chamber angles exceeding 55° resulted in increases in ROM-I and ROM-D values, but decreases in PRM, Energy-D, and DRI values, which, in turn, increased the likelihood of dislocation. （4） The cup, which was reduced posteriorly, reduced ROM-I values （2.1-5.3-°） and increased the DRI value （0.073）. This suggested that the posterior high side 展开更多
基金the Natural Youth Science Foundation of Fujian Province(No.2017J05006)the National Natural Science Foundation of China(No.51575196)+1 种基金the Subsidized Project for Postgraduates’Innovation Fund in Scientific Research of Huaqiao University(Nos.18014080034 and 19013080038)the Case Base of Graduate Programs for Professional Degree of Huaqiao University(No.18YJG25)。
文摘With the development of economy and the progress of medical science and technology,artificial prosthesis replacement has become an important means to improve the dysfunction caused by human bone diseases.However,there are still some loose phenomena caused by stress shielding.To solve the complications of aseptic loosening after calcaneal prosthesis replacement,an optimal design method for the prosthesis was proposed.The prosthesis was designed and optimized according to the real bone shape and the replacement requirements by the combination of computed tomography(CT)technology,computer-aided design,finite element analysis,and power flow theory.CT data were imported into MIMICS and Geomagic Studios.UG was used to obtain the geometric model of the human skeleton.Then,the 3D finite element model of the prosthesis was established by combining the finite element software Abaqus,and a series of finite element analysis was carried out.The prosthesis was topologically optimized and filled with a porous structure.The prosthesis was implanted by computer simulation.Finally,the power flow method was used to compare the dynamic performance and energy transfer before and after the prosthesis replacement to verify the rationality of the prosthesis design.In this paper,this method was used to optimize the design of the calcaneal prosthesis,and the research shows that this method can reduce the stress shielding effect of the calcaneal prosthesis.From the case of calcaneal prosthesis optimization,this method is not only a supplement to the contemporary biomechanical theory but also can guide the design of bone prosthesis in bone prosthesis replacement surgery.
文摘During the modern city construction,the conservation of the historic buildings is especial important,for the future development is based on the historic accumulation.Timber element,which is the common material in the historic buildings,always sufferd by the varies natural or man-made factors,and finally lead to huge threaten to the entire structure.The conservation methods often changing according to the different circumstances and degree of destruction.This paper has introduced two approaches,repair and replacement,compared the advantages and disadvantages of each,and then summary the application of two methods in the light of conservation principle.
文摘Background Dislocation is the second most common complication of hip replacement surgery, and impact of the prosthesis is believed to be the fundamental reason. The present study employed Solidworks 2003 and MSC-Nastran software to analyze the three dimensional variables in order to investigate how to prevent dislocation following hip replacement surgery. Methods Computed tomography （CT） imaging was used to collect femoral outline data and Solidworks 2003 software was used to construct the cup model with variabilities. Nastran software was used to evaluate dislocation at different prosthesis positions and different geometrical shapes. Three dimensional movement and results from finite element method were analyzed and the values of dislocation resistance index （DRI）, range of motion to impingement （ROM-I）, range of motion to dislocation （ROM-D） and peak resisting moment （PRM） were determined. Computer simulation was used to evaluate the range of motion of the hip joint at different prosthesis positions. Results Finite element analysis showed： （1） Increasing the ratio of head/neck increased the ROM-I values and moderately increased ROM-D and PRM values. Increasing the head size significantly increased PRM and to some extent ROM-I and ROM-D values, which suggested that there would be a greater likelihood of dislocation. （2） Increasing the anteversion angle increased the ROM-I, ROM-D, PRM, energy required for dislocation （ENERGY-D） and DRI values, which would increase the stability of the joint. （3） As the chamber angle was increased, ROM-I, ROM-D, PRM, Energy-D and DRI values were increased, resulting in improved joint stability. Chamber angles exceeding 55° resulted in increases in ROM-I and ROM-D values, but decreases in PRM, Energy-D, and DRI values, which, in turn, increased the likelihood of dislocation. （4） The cup, which was reduced posteriorly, reduced ROM-I values （2.1-5.3-°） and increased the DRI value （0.073）. This suggested that the posterior high side
