天鹅记忆加压接骨器对肱骨骨折加载应力的选择

背景肱骨骨折治疗中经常遇到的主要问题在于应力加载的方向与应力加载的力值.目的分析天鹅记忆加压接骨器固定肱骨时不同应力加载的选择,为今后肱骨骨折治疗时内固定器械的放置部位、载荷的施加方向及大小等提供力学依据.设计进行不同应力加载的条件下,构建肱骨骨折的三维有限元模型.单位解放军第二军医大学附属长海医院骨科和同济大学生命科学与生物工程学院.材料实验于2001-01/2003-05在解放军第二军医大学长海医院骨科实验室和同济大学生命科学与生物工程学院实验室完成.选取湿成年尸体肱骨标本和与之相对应型号的天鹅型记忆接骨器.方法选择湿肱骨标本行CT成像得到肱骨每层横截面图像,采用大型有限元分析软件ANSYS 5.6建立肱骨、天鹅型记忆接骨器以及天鹅型记忆接骨器固定肱骨的三维模型.主要观察指标对比不同加载方式下肱骨的受力情况,寻求临床治疗的参考数值.结果所构建天鹅型记忆接骨器固定肱骨三维模型,逼真反映真实解剖形态及生物力学行为,同时获得不同加载方式下肱骨的受力情况.结论天鹅型记忆接骨器固定肱骨三维有限元模型的构建,可以为肱骨正常力学行为以及骨折后内固定的力学基础研究提供精确模型.

Choice of the loading stress during the fracture fixation of humerus using Swain Memory Compression Bone Reduction Apparatus

BACKGROUND: During the therapy of the fracture of humerus, the main problem is the loading direction and power of the stress.OBJECTIVE: To analyze the choice of the different loading manners using Swain Memory Compression Bone Reduction Apparatus so as to provide the clinical evidence for the set position of the internal fixation apparatus, the loading direction and power during the therapy of the fracture of humerus.DESIGN: To construct the three-dimensional finite element model of the fracture of humerus with different loading manners.SETTING: Department of Orthopaedics of Changhai Hospital of Second Military Medical University of Chinese PLA; College of Life Sciences and Bioengineering of Tongji University,MATERIALS: The study was conducted during the period from January 2001 to May 2003 in the Orthopedic Laboratory of Changhai Hospital of Second Military Medical University of Chinese PLA and the laboratory of Life Science and Bioengineering Academy of Tongji University. The samples of the humerus taken from the wet adult cadavers, and the Swain Memory Compression Bone Reduction Apparatuses of the corresponding size were prepared.METHODS: The CT scanning was done on the samples of the wet humerus to obtain the cross section image of each layer of the humerus.The images were analyzed by a large-scale finite element analysis software ANSYSS.6 to construct the three-dimensional model of the humerus, Swain Memory Bone Reduction Apparatus and the fixed humerus using Swain Memory Bone Reduction Apparatus.MAIN OUTCOME MEASURES: To get the reference values for the clinical therapy through the comparison of the power endurance with different loading manners.RESULTS: The three-dimensional model of the fixed humerus using Swain Memory Bone Reduction Apparatus reflects the real anatomical configuration and the biomechanics behavior; meanwhile the status of the power endurance of humerus with different loading manners is also obtained.CONCLUSION: The three-dimensional model of the fixed humerus using Swain Memory Bone Reduction Apparatus may provide an accurate model for the basic study of the biomechanics behavior of the normal and fixed humerus after the fracture.