# Biomechanical Optimization of Lumbar Fusion Cages with a Porous Design: A Finite Element Analysis
## 5 Conclusions  
This study utilized finite element analysis to evaluate the biomechanical performance of four lumbar interbody fusion cage designs (C-cage, P-cage, G-cage, and V-cage) in the L3-L4 spinal segment. The results demonstrated that the V-Cage, with its biomimetic Voronoi porous structure, outperforms other designs by significantly reducing the range of motion (51% in Extension), cage stress (41.7% in A-Compression), and endplate stress (63.7% in L-Bending) when compared to the C-Cage. These improvements were attributed to its ability to distribute mechanical loads uniformly, mimicking the anisotropic properties of natural trabecular bone, thereby enhancing spinal stability and minimizing subsidence risk. Additionally, the G-Cage also exhibited notable benefits over the control C-cage design, though it was less effective than the V-Cage due to its isotropic Gyroid structure. In contrast, the P-Cage, featuring personalization but lacking porosity, showed limited biomechanical advantages. These findings underscore the transformative potential of integrating patient-specific geometry with porous architectures in interbody fusion cages. As such, the V-Cage design investigated in this work offers a compelling alternative for potentially improving fusion outcomes and reducing postoperative complications, thus providing a foundation for advancing personalized, porous implant designs in spinal surgery.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app15105384/s1](https://www.mdpi.com/article/10.3390/app15105384/s1)]([https://www.mdpi.com/article/10.3390/app15105384/s1](https://www.mdpi.com/article/10.3390/app15105384/s1)), Table S1. Comparison of the displacement of the complete finite element model (mm); Table S2. Comparison of the ROM of the complete finite element model (Deg); Table S3. Maximum stress for cages of L3-L4 segment in six motion modes (MPa); Table S4. Maximum stress for L3 endplate with different cages in six motion modes (MPa); Table S5. Maximum stress for L4 endplate with different cages in six motion modes (MPa).  
Conceptualization, C.Z.; methodology, K.D.; software, K.D.; validation, Z.S.; formal analysis, Y.W.; investigation, C.Z.; resources, C.Z.; writing--original draft preparation, C.Z.; writing--review and editing, Z.S.; supervision, C.Z.; project administration, C.Z.; funding acquisition, C.Z. All authors have read and agreed to the published version of the manuscript.  
This work was supported in part by Ningbo Key Projects of Science and Technology (No. 2023Z192).  
The study was conducted in accordance with the Declaration of Helsinki, and approved by the Ethics Committee of First Affiliated Hospital of Ningbo University (Approval Number: 2024-05-1, Date: 5 June 2024).  
Informed Consent Statement: Informed consent was obtained from all subjects involved in the study.  
Data Availability Statement: Data available on request due to restrictions of privacy: the data presented in this study are available on request from the corresponding author.  
The authors declare no conflicts of interest.