带血管蒂的骨膜瓣治疗距骨缺血性坏死过程中不同骨隧道的三维有限元分析

发布时间：2018-04-11 00:00

本文选题：距骨缺血性坏死 + 骨隧道　；参考：《遵义医学院》2015年硕士论文

【摘要】：目的:应用三维有限元建立正常距骨模型、距骨缺血性坏死模型及打入骨髓道后坏死距骨模型。分析正常距骨、坏死距骨、打入骨髓道后坏死距骨表面的应力及位移数据变化,找出最合适的骨隧道位置,为临床治疗距骨缺血性坏死提供参考。方法:对正常人的踝关节行64排薄层螺旋CT扫描获得人踝关节的三维数据,通过图像处理软件建立几何模型,导入到有限元软件中生成距骨的三维有限元实验模型,参照文献模拟距骨坏死模型,另模拟在距骨体-颈交界部位打入骨隧道,挖出死骨,再植入人工骨,分析人自然站立位时距骨表面的应力及位移数据变化,从中找出对距骨表面应力及位移影响最小的骨隧道方向。结果:我们成功建立了距骨的三维有限元模型图,共有节点159271个,单元122442个,其中松质骨110898个,密质骨11544个。建立的距骨形态还原性良好。当距骨外侧坏死时,在应力方面,坏死距骨表面应力明显大于正常距骨表面应力;打入骨隧道后坏死距骨表面应力均小于坏死距骨表面应力,但是均大于正常距骨表面应力,内侧骨隧道距骨表面应力最小;位移方面,坏死距骨位移小于正常距骨位移;外侧、中部、内侧骨隧道距骨位移均大于正常及坏死距骨位移。距骨内侧坏死后,在应力方面,结果同距骨外侧坏死,外侧、中部、内侧骨隧道距骨表面应力比较,中部的应力最小。在位移方面,距骨内侧坏死的位移同距骨外侧坏死,外侧、中部、内侧骨隧道距骨位移比较,变化不大,中部及内侧的位移相同,小于外侧的位移。结论:通过本次实验,我们成功建立了正常距骨、坏死距骨和打入骨髓道后坏死距骨的三维有限元模型,并观察了当人自然站立位时,正常距骨、坏死距骨、打入骨髓道后坏死距骨的应力云图及位移云图,实验结果发现当距骨发生坏死时,距骨的力学环境发生明显变化,表面应力明显大于正常距骨表面应力,通过有限元软件模拟对坏死距骨打入骨隧道后,距骨表面应力均明显小于坏死距骨表面应力,但均大于正常距骨表面应力,说明内、中、外侧3种骨隧道在恢复距骨力学坏境方面有所贡献,但均无法让距骨的力学环境恢复正常;另外,我们通过对不同骨隧道进行比较发现:当距骨外侧发生坏死时,从距骨颈-体部交界部位内侧打入骨隧道后,距骨表面应力最接近于正常距骨表面应力,对距骨的表面应力影响最小,应属最佳方案;当距骨内侧发生坏死时,内、中、外侧3种骨隧道距骨表面应力变化不大,但相比较而言,中间骨隧道距骨表面应力最接近于正常距骨表面应力,对距骨表面应力影响最小,可作为最佳方案。
[Abstract]:Objective: to establish the normal talus model, the talus ischemic necrosis model and the talus model after penetrating the bone marrow canal by using three dimensional finite element method.The data of stress and displacement on the surface of the necrotic talus after penetrating into the bone marrow tract were analyzed to find out the most suitable location of the bone tunnel and to provide a reference for clinical treatment of avascular necrosis of the talus.Methods: the 3D data of human ankle were obtained by 64 row spiral CT scanning of ankle joint. The geometric model was established by image processing software, and the three-dimensional finite element model of talus was generated by introducing it into the finite element software.According to the model of talus osteonecrosis, the model of talus osteonecrosis was simulated, and the dead bone was dug out at the junction of talus and neck, and then the artificial bone was implanted. The data of stress and displacement on the surface of talus were analyzed when the human was standing naturally.The direction of bone tunnel which has the least influence on the surface stress and displacement of talus is found out.Results: we successfully established the three-dimensional finite element model of talus. There were 159271 nodes and 122442 units, of which the cancellous bone was 110898 and the dense bone was 11544.The shape of talus was reduced well.When the lateral talus is necrotic, the surface stress of the necrotic talus is obviously greater than that of the normal talus, the surface stress of the necrotic talus is smaller than that of the necrotic talus, but the surface stress of the necrotic talus is larger than that of the normal talus.The displacement of necrotic talus is smaller than that of normal talus, and that of lateral, middle and medial tunnel is greater than that of normal and necrotic talus.After the medial talus necrosis, the stress in the middle part of the talus was the smallest compared with the lateral necrosis, lateral necrosis, middle part and medial tunnel of talus.In terms of displacement, the displacement of medial necrosis of talus is similar to that of lateral necrosis, lateral, middle and medial bone tunnel of talus. The displacement of middle and medial talus is the same and smaller than that of lateral.Conclusion: through this experiment, we have successfully established the three-dimensional finite element model of normal talus, necrotic talus and necrotic talus after penetrating into bone marrow tract, and observed the normal talus and necrotic talus when people were standing naturally.The stress cloud image and displacement cloud image of the necrotic talus after penetrating into the bone marrow tract. The experimental results show that the mechanical environment of the talus changes obviously when the talus necrosis occurs, and the surface stress is obviously larger than that of the normal talus surface stress.After penetrating the necrotic talus into the tunnel by the finite element software, the surface stress of the talus is obviously smaller than that of the necrotic talus, but higher than that of the normal talus.Three kinds of lateral bone tunnels have contributed to the restoration of mechanical condition of talus, but none of them can make the mechanical environment of talus return to normal. In addition, we have compared different bone tunnels and found that: when the lateral talus necrosis occurs,After penetrating into the tunnel from the medial part of the talus neck-body junction, the surface stress of the talus is the closest to the normal one, which has the least influence on the surface stress of the talus.However, the surface stress of talus in the middle tunnel was the closest to the normal one, and had the least effect on the surface stress of talus.
【学位授予单位】：遵义医学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R687.3

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