A finite element modeling of posterior atlantoaxial fixation and biomechanical analysis of C2 intralaminar screw fixation

• Published in: Chinese medical journal Vol. 127; no. 7; pp. 1266 - 1271
• Main Authors: Ma, Xuexiao, Peng, Xianbo, Xiang, Hongfei, Zhang, Yan, Zhang, Guoqing, Chen, Bohua
• Format: Journal Article
• Language: English
• Published: China Department of Orthopaedic Surgery, the Affiliated Hospital of Qingdao University, Qingdao, Shandong 266003, China 2014
• Subjects: Biomechanical Phenomena; Bone Screws; Cervical Vertebrae - surgery; Finite Element Analysis; Humans; Range of Motion, Articular; 三维有限元模型; 内固定; 内核; 力学分析; 有限元建模; 枢椎; 椎弓根螺钉; 生物力学; pedicle screw; upper cervical spine; intralaminar screw; biomechanics; finite elements
• ISSN: 0366-6999; 2542-5641
• DOI: 10.3760/cma.j.issn.0366-6999.20122928

Background The objective of this study was to use three-dimensional finite element （FE） models to analyze the stability and the biomechanics of two upper cervical fixation methods：the C2 intralaminar screw method and the C2 pedicle screw method.Methods From computed tomography images,a nonlinear three-dimensional FE model from C0 （occiput） to C3 was developed with anatomic detail.The C2 intralaminar screw and the C2 pedicle screw systems were added to the model,in parallel to establish the interlaminar model and the pedicle model.The two models were operated with all possible states of motion and physiological loads to simulate normal movement.Results Both the C2 intralaminar screw method and the C2 pedicle screw method significantly reduced motion compared with the intact model.There were no statistically significant differences between the two methods.The Von Mises stresses of the internal and external laminar walls were similar between the two methods.Stability was also similar.Conclusions The C2 intralaminar screw method can complement but cannot completely replace the C2 pedicle screw method.Clinicians would need to assess and decide which approach to adopt for the best therapeutic effect.