Baca Vaclav, Horak Zdenek, Mikulenka Petr, Dzupa Valer
Department of Anatomy, 3rd Faculty of Medicine, Charles University in Prague, Prague, Czech Republic.
Med Eng Phys. 2008 Sep;30(7):924-30. doi: 10.1016/j.medengphy.2007.12.009. Epub 2008 Feb 20.
Finite element (FE) analysis has been widely used to study the behaviour of bone or implants in many clinical applications. One of the main factors in analyses is the realistic behaviour of the bone model, because the behaviour of the bone is strongly dependent on a realistic bone material property assignment. The objective of this study was to compare isotropic and orthotropic inhomogeneous material models used for FE analyses of the "global" proximal femur and "small" specimens of the bone (cancellous and cortical). Our hypothesis was that realistic material property assignment (orthotropy) is very important for the FE analyses of small bone specimens, whereas in global FE analyses of the proximal femur, this assignment can be omitted, if the inhomogeneous material model was used. The three-dimensional geometry of the "global" proximal femur was reconstructed using CT scans of a cadaveric femur. This model was implemented into an FE simulation tool and various bone material properties, dependant on bone density, were assigned to each element in the models. The "small" specimens of cortical and cancellous bone were created in the same way as the model of the proximal femur. The results obtained from FE analyses support our above described hypothesis.
有限元（FE）分析已广泛应用于许多临床应用中，用于研究骨骼或植入物的行为。分析中的一个主要因素是骨骼模型的真实行为，因为骨骼的行为强烈依赖于真实的骨材料属性赋值。本研究的目的是比较用于“整体”近端股骨和骨骼“小”标本（松质骨和皮质骨）有限元分析的各向同性和正交各向异性非均匀材料模型。我们的假设是，对于小骨标本的有限元分析，真实的材料属性赋值（正交各向异性）非常重要，而在近端股骨的整体有限元分析中，如果使用非均匀材料模型，则可以省略此赋值。使用尸体股骨的CT扫描重建了“整体”近端股骨的三维几何形状。该模型被应用到一个有限元模拟工具中，并且根据骨密度为模型中的每个单元赋予了各种骨材料属性。皮质骨和松质骨的“小”标本以与近端股骨模型相同的方式创建。有限元分析得到的结果支持我们上述假设。
