摘要
背景:有限元法最核心的部分就是有限元模型的建立,所建立模型的精确度和建模所需的时间直接体现了该方法的可行与有效性。随着建模方法的发展,骨科有限元分析的范围也逐渐从早期的股骨拓展到脊柱、四肢,而采用DICOM数据直建模法建立儿童肱骨模型并进行有限元分析,国内外文献尚未见相关报道。目的:建立并验证儿童肱骨三维有限元模型,并应用该模型探讨儿童肱骨髁上骨折和肘内翻发生的机制。设计、时间及地点:观察验证性实验,于2007-07/09在大连交通大学机械工程学院CAD/CAE研究中心完成。对象:选择山西医科大学第二医院放射科1例左肱骨髁间粉碎骨折患者CT图像,男性,4岁,采集右侧对照CT图像。方法:扫描层厚为1.25mm,无间隔,将所得图像数据导入到医学图像处理软件mimics中,生成肱骨三维模型。然后以IG格式输出导入到专业有限元网格制作软件HYPERMESH中,生成三维有限元模型。最后导入有限元分析软件ANSYS进有限元分析。主要观察指标:不同载荷下尺侧和桡侧平均应力值。结果:①模型检验与体外生物力学实验的数据基本一致。②肱骨髁上区可见明显的应力交界区。③肱骨尺侧应力大于桡侧结论:①本实验所建立模型真实可信,可用于生物力学分析。②肱骨髁上骨折模型与实际骨折基本一致,进一步形象地实了肱骨髁上骨折发生于骨形状及皮松质骨交界区。③尺侧皮质受损大于桡侧是肘内翻畸形的基本力学因素。
BACKGROUND： Establishment of finite element model is the key in finite element analysis. The accuracy and modeling time cost directly reflect the feasibility and validity of modeling method. With the development of model establishment, the scope of finite element analysis for orthopedics department is expanded from early femur to spine and extremities. To date, there are no reports about DICOM data method for child humeral modeling and finite element analysis at home and abroad. OBJECTIVE： To set up and verify the finite element model of child humerus and to analyze the injury mechanisms of supracondylar humeral fracture and cubitus varus. DESIGN, TIME AND SETTING： The observation was performed at CAD/CAS Research Center, College of Mechanical Engineering, Dalian Jiaotong University from July to September 2007. PARTICIPANT： CT images of a 4-year-old male child with comminuted fracture of left humeral condyle were collected from Department of Radiology, Second Hospital of Shanxi Medical University. The CT images of the right side served as control. METHODS： The humeral condyle was scanned by CT with 1.25 mm interval. The CT images were （DICOM） were dealt with MIMICS to form 3-dimentional （3D） humeral model. Then the model was output by IGS form and put in HYPERMESH software to build up 3D finite element model. Finally, the model was put in the ANSYS software for finite element analysis. MAIN OUTCOME MEASURES： Average ulnar and radial stress under different loads. RESULTS： The model kept coincidence with the data of biomechanical experiment in vitro. A clear junctional zone was found on the supracondylar humerus. The ulnar stress was larger than the radial stress. CONCLUSION： The model is reliable and can be used for biomechanical analysis. The fracture model of supracondylar humerus is almost identical to practical fracture, indicating the fracture of supracondylar humerus occurs in the juncture of cortical bone and cancellous bone. Damage of ulnar cortex larger than the radialis is the bas
出处
《中国组织工程研究与临床康复》
CAS
CSCD
北大核心
2008年第22期4265-4269,共5页
Journal of Clinical Rehabilitative Tissue Engineering Research
