Close collaboration between surgeons and engineers is paramount in the intricate process of designing and evaluating hip joint prostheses. In revision surgeries, cement spacers play a vital role, but their effectiveness hinges on the reinforcement of the cement, bone, and femur to minimize stress. To assess the fracture behavior of reinforced spacers, we employ a comprehensive three-dimensional approach that analyzes the three primary materials used for full stems: titanium, ceramics, and stainless steel. Our analysis focuses on evaluating the von Mises stress and stress intensity factor along the crack tip using linear elastic analysis. Additionally, we utilize the extended finite element Method (X-FEM) to simulate crack initiation and propagation in non-reinforced cement spacers. By comparing the results obtained from these two methods, we gain valuable insights into the influence of different materials on the performance and durability of reinforced spacers. Our findings unequivocally demonstrate that reinforcing spacers with ceramic and stainless-steel full stems are exceptionally effective techniques for enhancing the strength of hip spacers. Specifically, we observed a significant reduction of stress levels by 30% in various hip prosthesis components, along with a notable 23% decrease in the stress intensity factor for spacers reinforced with ceramic stems. These insights are invaluable for spacer designers and can contribute significantly to improving the durability of hip joint prostheses, ultimately minimizing the need for early hip revisions.

中文翻译：

---

分析髋关节水泥垫片的性能：通过多尺度方法研究裂纹行为

在设计和评估髋关节假体的复杂过程中，外科医生和工程师之间的密切合作至关重要。在翻修手术中，骨水泥垫片起着至关重要的作用，但其有效性取决于骨水泥、骨骼和股骨的加固以最大限度地减少压力。为了评估增强垫片的断裂行为，我们采用了全面的三维方法来分析用于全柄的三种主要材料：钛、陶瓷和不锈钢。我们的分析重点是使用线弹性分析评估沿裂纹尖端的 ​​von Mises 应力和应力强度因子。此外，我们利用扩展有限元方法 (X-FEM) 来模拟非增强水泥垫片中的裂纹萌生和扩展。通过比较这两种方法获得的结果，我们获得了关于不同材料对增强垫片性能和耐久性的影响的宝贵见解。我们的研究结果明确表明，采用陶瓷和不锈钢全柄加固垫片是增强髋部垫片强度的极其有效的技术。具体来说，我们观察到各种髋关节假体组件的应力水平显着降低了 30%，而陶瓷柄增强垫片的应力强度因子显着降低了 23%。这些见解对于垫片设计者来说非常宝贵，可以显着提高髋关节假体的耐用性，最终最大限度地减少早期髋关节翻修的需要。