There is a large gap between the elastic modulus of the existing femoral stem and the host bone. This gap can lead to long-term complications, such as aseptic loosening and, eventually, a need for revision surgery. The porous metallic biomimetic femoral stem can effectively reduce stress shielding and provide firm implant fixation through bone ingrowth. The purpose of this research is to investigate the application of different porous femoral stems in relieving bone resorption and promoting osseointegration by finite element analysis. We present an intuitive visualization method based on a diamond lattice structure to understand the relationship between pore size, porosity, bone ingrowth criteria and additive manufacturing constraints. We further obtain an admissible design space of diamond lattice structure for porosity selection. We evaluate the relative micromotion of bone-implant interface and bone volume with density loss for three femoral stems with diamond lattice-based homogenous porous structures in admissible design space. We also evaluate porous femoral stems with four different grading orientations along the axial and radial directions of the femoral stem. These include an axial graded femoral stem with a porosity increased distally (DAGS), an axial graded femoral stem with a porosity increased proximally (PAGS), a radial graded femoral stem with a porosity increased inwardly (IRGS), and a radial graded femoral stem with a porosity increased externally (ERGS). The results indicate that: (i) homogenous porous femoral stems with 40% porosity, (ii) DAGS and (iii) IRGS can maintain the relative micromotion of the bone-implant interface in the safety range for bone ingrowth. The calculated volumes of bone with density loss in the cases of DAGS and IRGS are 3.6% and 3.3%, respectively, which are nearly 74% lower than that of fully dense stems. Therefore, DAGS and IRGS have an evident advantage in promoting osseointegration and relieving bone resorption. Thus, the graded femoral stem is more promising than the homogeneous porous stem.

现有股骨柄与宿主骨之间的弹性模量之间存在较大的差距。这种差距可能导致长期并发症，例如无菌性松动，最终需要翻修手术。多孔金属仿生股骨柄可有效减少应力屏蔽，并通过骨向内生长提供牢固的植入物固定。本研究的目的是通过有限元分析研究不同的多孔股骨柄在缓解骨吸收和促进骨整合方面的应用。我们提出了一种基于钻石晶格结构的直观可视化方法，以了解孔径，孔隙率，骨长入标准和增材制造约束条件之间的关系。我们进一步获得了用于孔隙率选择的金刚石晶格结构的允许设计空间。我们在允许的设计空间中评估了三个具有基于金刚石晶格的均质多孔结构的股骨柄的骨-植入物界面和骨量的相对微运动以及密度损失。我们还评估了沿股骨干的轴向和径向具有四个不同渐变方向的多孔股骨干。这些包括向远端增加孔隙度的轴向分级股骨柄（DAGS），向近端增加孔隙度的轴向分级股骨柄（PAGS），向内增加孔隙度的径向分级股骨柄（IRGS）和径向分级的股骨柄外部孔隙率增加（ERGS）。结果表明：（i）孔隙率为40％的均质多孔股骨柄，（ii）DAGS和（iii）IRGS可以将骨-植入物界面的相对微动保持在骨骼向内生长的安全范围内。在DAGS和IRGS情况下，具有密度损失的骨的计算量分别为3.6％和3.3％，比完全致密的茎的骨量减少了近74％。因此，DAGS和IRGS在促进骨整合和减轻骨吸收方面具有明显的优势。因此，分级股骨柄比均质多孔茎更有前途。