Zhou Ziyao, Shi Xiaogang, Peng Jiahui, Zhou Xiaoxiao, Yang Liuqing, Zhong Zhijun, Liu Haifeng, Peng Guangneng, Zheng Chengli, Zhang Ming
Teaching Veterinary Hospital, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China.
Sichuan Wolong National Natural Reserve Administration Bureau, Wenchuan 623006, China.
Vet Sci. 2025 Jul 19;12(7):682. doi: 10.3390/vetsci12070682.
Pedicle screw fixation is a critical technique for stabilizing lumbar fractures in canines, yet the biomechanical implications of insertion angles remain underexplored. This study aims to identify optimal screw trajectories by analyzing stress distribution and deformation patterns in beagle lumbar segments (L6-L7) using finite element analysis (FEA). A 3D finite element model was reconstructed from CT scans of a healthy beagle, incorporating cortical/cancellous bone, intervertebral disks, and cartilage. Pedicle screws (2.4 mm diameter, 22 mm length) were virtually implanted at angles ranging from 45° to 65°. A 10 N vertical load simulated standing conditions. Equivalent stress and total deformation were evaluated under static loading. The equivalent stress occurred at screw-rod junctions, with maxima at 50° (11.73 MPa) and minima at 58° (3.25 MPa). Total deformation ranged from 0.0033 to 0.0064 mm, with the highest at 55° and the lowest at 54°. The 58° insertion angle demonstrated optimal biomechanical stability with minimal stress concentration, with 56-60° as a biomechanically favorable range for pedicle screw fixation in canine lumbar fractures, balancing stress distribution and deformation control. Future studies should validate these findings in multi-level models and clinical settings.
椎弓根螺钉固定是稳定犬腰椎骨折的关键技术，但植入角度的生物力学影响仍未得到充分研究。本研究旨在通过有限元分析（FEA）分析比格犬腰椎节段（L6-L7）的应力分布和变形模式，以确定最佳螺钉轨迹。从一只健康比格犬的CT扫描重建了一个三维有限元模型，纳入了皮质骨/松质骨、椎间盘和软骨。将直径2.4mm、长度22mm的椎弓根螺钉以45°至65°的角度虚拟植入。10N的垂直载荷模拟站立状态。在静态载荷下评估等效应力和总变形。等效应力出现在螺钉-棒连接处，在50°时最大（11.73MPa），在58°时最小（3.25MPa）。总变形范围为0.0
