文献类型：期刊文献

中文题名：骨质疏松症患者脊柱胸腰段椎体力学稳定性变化与椎体压缩性骨折风险预测的有限元分析

英文题名：Spinal thoracolumbar vertebrae stability change and risk prediction of vertebral compression fracture in osteoporosis patients:a finite element analysis

作者：秦大平[1,2];张晓刚[2];权祯[1];张华[1];曹林忠[1];陈钵[1];徐斌[1];徐世伟[2]

第一作者：秦大平

机构：[1]甘肃中医药大学中医临床学院,甘肃兰州730000;[2]甘肃中医药大学附属医院脊柱外科,甘肃兰州730020

第一机构：甘肃中医药大学中医临床学院

年份：2021

卷号：38

期号：4

起止页码：485

中文期刊名：中国医学物理学杂志

外文期刊名：Chinese Journal of Medical Physics

收录：CSTPCD;;CSCD:【CSCD_E2021_2022】；

基金：国家自然科学基金(81760873);甘肃省高等学校创新基金项目(2020A-073);甘肃中医药大学附属医院青年创新基金(gzfy-2018-11)。

语种：中文

中文关键词：骨质疏松症;力学稳定性;胸腰椎压缩性骨折风险预测;有限元分析

外文关键词：osteoporosis;mechanical stability;prediction of thoracolumbar compression fracture risk;finite element analysis

摘要：目的:通过有限元分析骨质疏松症(OP)患者的脊柱胸腰段椎体在不同运动状态下椎体力学稳定性变化,与人体正常模型进行对比分析,针对椎体是否存在压缩性骨折的风险进行预测,为干预性策略标准化建立和完善提供理论和生物力学依据。方法:选择没有脊柱胸腰段椎体伤病史的健康志愿者男女各1人;选择2例住院老年OP女性患者胸腰椎CT及MRI扫描资料。建立T11~L2骨质疏松性椎体的三维有限元模型并验证有效性。在正常生理载荷分析不同运动状态下的生物力学变化,对两组模型之间椎体、关节突关节、终板、纤维环、松质骨、椎间盘、髓核的Von Mises应力及椎体最大位移进行比对分析,同时对应力云图进行比对,分析其生理与病理关节应力变化。结果:正常人体与OP患者脊柱椎体的材料属性、弹性模量、刚度、强度以及所处的力学生物学环境变化进行分析结果表明,OP患者在脊柱前屈、后伸、左右侧弯、左右旋转、轴向7种不同运动状态下与正常人体脊柱胸腰段相比较,椎体、关节突关节、椎间盘、终板、纤维环、髓核的Von Mises应力有明显降低趋势,椎体最大位移呈现增大趋势。此外本研究对OP模型的建立并非采用文献中降低正常皮质骨、松质骨、终板弹性模量的模型,而是采用临床中根据CT数据、临床症状、骨密度等明确诊断的OP患者数据,与目前文献所提供的模型数据对比,更符合临床OP患者真实的脊柱胸腰段椎体与附属结构的生物力学特性和属性变化。与正常人体模型相比较,从筋骨系统进行分析,骨与肌肉、韧带所代表的动静力变化都有明显降低,这也印证了临床真实数据的变化。结论:OP患者脊柱胸腰段椎体应力分布不均匀、应力的集中趋势导致脊柱胸腰段椎体、椎间盘、髓核、纤维环、关节突及周围附属结构应力异常变化,即骨弹性模量的异常改变、周围附属结构的束缚力下降,引起筋骨系统平衡失常和长期稳定性下降,进而增加脊柱胸腰段椎体骨折的退变过程和风险,通过有限元分析针对椎体压缩性骨折风险建立标准化预防策略,提供理论和生物力学依据。
Objective To apply finite element analysis for analyzing the changes of the mechanical stability of the thoracolumbar vertebrae in osteoporosis patients in different motion states,and then compare the established finite element model with the normal human model,and to predict the risk of compression fracture,thereby providing theoretical and biomechanical basis for the standardization of intervention strategy.Methods A male volunteer who didn’t had the history of spinal thoracolumbar vertebrae injuries were enrolled in the study.Moreover,the thoracolumbar CT and MRI scan data of 2 hospitalized elderly osteoporosis women were selected to establish a three-dimensional finite element model of the osteoporotic vertebral body T11-L2,and then the validity of the established model was verified.The biological forces in different motion states under normal physiological load was analyzed;and the Von Mises stresses of vertebral body,articular process joint,endplate,fibrous ring,cancellous bone,intervertebral disc and nucleus pulposus,and the maximal displacement of vertebral body were compared between two groups;and finally,the physiological and pathological joint stress changes were analyzed using stress cloud map.Results The analysis on the material properties,elastic modulus,stiffness,strength of normal human spine and thoracolumbar spine in osteoporosis patients and the changes of mechanical and biological environment showed that the Von Mises stresses of vertebral body structure including vertebral body,articular process joint,intervertebral disc,end plate,fibrous ring and nucleus pulposus in osteoporosis patients under 7 motion states(forward flexion,extension,left and right lateral bending,left and right rotation,axial motion)were decreased significantly and the maximum displacement of vertebral body showed an increasing trend.In addition,the study established an osteoporosis model using clinical CT data and patients who were diagnosed with osteoporosis confirmed by specific clinical symptoms and bone mineral density,instead of adopting the model with reduced elastic modulus of cortical bone,cancellous bone and endplate which was provided in literatures.Compared with the model provided in the current literatures,the model established in the study was more consistent with the biomechanical characteristics and attribute changes of the actual spinal thoracolumbar vertebral body and accessory structure in osteoporosis patients.The analysis on musculoskeletal system showed that compared with those of normal human model,the dynamic and dynamic changes represented by bone,muscle and ligament of the model established in the study were significantly decreased,which also confirmed the change of clinical real data.Conclusion The uneven stress distribution and the tendency of stress concentration in thoracolumbar vertebrae in osteoporosis patients lead to abnormal changes of stresses in thoracolumbar vertebrae,intervertebral disc,nucleus pulposus,fibrosis,articular process and surrounding accessory structures,namely the abnormal change of elastic modulus of bone and the decrease of binding force of surrounding accessory structures,which will result in imbalance of musculoskeletal system and decrease of long-term stability,thus increasing the degeneration and risk of thoracolumbar compression fracture.The study also provide theoretical and biomechanical basis for the standardization of intervention strategy for thoracolumbar compression fracture risk.