颈椎生理曲度变直全节段有限元建模与分析

Finite element modeling and analysis for cervical spine with straightened physiological curvature

目的 建立生理曲度变直的颈椎全节段有限元模型,对颈椎生理曲度变直的发生机制进行验证与分析.方法 选取符合颈椎曲度变直纳入标准的患者,采集其CT数据,使用生物力学有限元建模软件,精确重建颈椎各节段的独立实体模型,直接从三维实体模型划分生成高质量有限元体网格,进一步精细生成各种韧带、椎间盘、关节突软骨等组织和结构.结果 在前屈、后伸、侧弯和旋转情况下,生理曲度变直的颈椎全节段有限元模型活动度范围比正常值范围要小并且出现再分配.同时,在应力分布方面,C3～4、C4～5 之间的小关节、钩突关节,和C3～4之间的椎间盘容易出现应力集中情况,表明易出现损伤和退化.结论 新型生物力学有限元建模软件简单易用,所建生理曲度变直的颈椎全节段有限元模型结构完整,空间结构精度高,单元划分规则精细,有限元分析结果对生理曲度变直的颈椎病临床诊断有指导意义.

Objective To establish a finite element model of complete cervical spine with straightened physiological curvature. Methods CT scan data of patients with straightened cervical spine were collected. By using specailly designed modeling system, the accurate solid model of separate cervial vertebra was created, which was subsequently meshed directly to build finite element volumetric mesh of high quality; then soft tissue structures were created inlcude detailed ligaments, disk and facet joint cartilage. Results Under the boundary conditions of flexion, extension, lateral bending and rotation, the results demonstrated that the active movement range of straightened cervical spine was limited with a different distribution pattern compared to normal configuration. For stress distribution, there were stress concentration at the facet joint cartilage and uncovertebral joint between C3-4, C4-5, and at the disk between C3-4. Conclusion The established finite element model of complete cervical spine with straightened physiological curvature has complete structure, accurate geometry, and regular element shape, which is of use in diagnosis and treatment of straightened physiological curvature.