3-D Visualization and Prediction of Vertebral Fractures

椎体骨折是骨质疏松性骨折中最常见的一种，每三名女性中就有一人受到影响， 六名50岁以上的男子。尽管其发病率很高，但对脊椎骨折的敏感和特异估计 风险仍然难以捉摸。当前评估脊柱强度和骨折的方法的局限性 风险在很大程度上依赖于平均骨矿密度(BMD)的测量，这一点得到了广泛的认识。 然而，在验证方面缺乏替代方法，并且明显优于 “平均骨密度”方法。我们最新的数据通过以下方式解决了知识和翻译方面的这一关键差距 演示定量计算机断层摄影在临床上可行的测量方法 (QCT)扫描以增强对脊椎衰竭的预测。使用QCT派生的分布测量 整个椎体的骨组织，我们发现椎体内异质性的大小 BMD可以更好地预测脊椎强度，在有脊椎的女性中比没有脊椎的女性更低 骨折。这些数据还表明，骨密度的多个特征空间分布(“模式”)在 脊椎可以提供高的骨骼强度，这些模式和强度之间的联系可能是 受邻近间盘(IVD)退变严重程度的影响。我们现在建议 明确椎体内骨密度异质性、椎体衰竭和IVD退行性变之间的关系 基于人群的研究和互补性的体外研究。Aim#1将使用病例对照研究设计 参加弗雷明翰心脏研究(FHS)的男性和女性先前获得的QCT扫描 多检测器QCT研究，以检验非均质性降低幅度与 增加了普遍骨折的风险。目标2将使用来自FHS的年龄和性别分层的随机样本 QCT队列以确定BMD的空间分布与IVD健康之间的关系，其次是EX 定义这些关联如何影响脊椎强度的活体研究。我们在AIM中的双重假设 第二，骨密度的空间分布模式与IVD的健康状况有关，而椎体强度取决于 空间BMD模式与IVDS提供的负荷分布之间的一致性。目标#3将 通过一种新的实验方法继续我们专注于临床的生物力学研究，提供 急需评估基于QCT的椎体失效有限元(FE)模型的准确性。这 AIM将检验这样的假设，即FE预测的准确性通过结合临床来提高 对IVD健康状况的可获得评估。这些目标加在一起，是朝着减轻 脊椎骨折。这项工作是对椎体内异质性现象的经济有效的研究。 在社区居住的人群中进行病例对照和生物力学的实验室研究 这种异质性的后果。结果将提供广泛适用的、综合的评估 脊椎健康，配有可翻译的工具，为评估骨折风险设定了新的标准。

Vertebral fractures are the most common type of osteoporotic fracture, afflicting one in three women and one in six men over the age of 50. Despite their high prevalence, sensitive and specific estimates of vertebral fracture risk have remained elusive. The limitations of current approaches for estimating vertebral strength and fracture risk, which rely heavily on measurement of the average bone mineral density (BMD), are widely recognized. However, alternative methods have been lacking with respect to validation and clear advantages over the “average BMD” approach. Our recent data address this critical gap in knowledge and translation by demonstrating the use of clinically feasible measurements made from quantitative computed tomography (QCT) scans to enhance predictions of vertebral failure. Using QCT-derived measures of the distribution of bone tissue throughout the vertebra, we have found that the magnitude of the intra-vertebral heterogeneity in BMD provides improved predictions of vertebral strength and is lower in women with vs. without vertebral fracture. These data also indicate that multiple, characteristic spatial distributions (“patterns”) of BMD within the vertebra can confer high bone strength, and that the associations between these patterns and strength may be modulated by the severity of degeneration in the adjacent intervertebral discs (IVDs). We now propose to define relationships among intra-vertebral heterogeneity in BMD, vertebral failure, and IVD degeneration in population-based studies and complementary ex vivo studies. Aim #1 will use a case-control study design with previously acquired QCT scans in men and women enrolled in the Framingham Heart Study (FHS) Multidetector QCT study to test the hypothesis that decreased magnitude of heterogeneity is associated with increased risk of prevalent fracture. Aim #2 will use an age- and sex-stratified, random sample from the FHS QCT cohort to determine associations between the spatial distribution of BMD and IVD health, followed by ex vivo studies that define how these associations can influence vertebral strength. Our dual hypotheses in Aim #2 are that the spatial patterns of BMD are associated with IVD health and that vertebral strength depends on the congruence between the spatial BMD pattern and the load distribution supplied by the IVDs. Aim #3 will continue our clinically focused, biomechanical investigations via a novel experimental approach that provides much-needed evaluation of the accuracy of QCT-based finite element (FE) models of vertebral failure. This aim will test the hypothesis that the accuracy of the FE predictions is improved by incorporating clinically obtainable assessments of IVD health. Together, these Aims are a major step towards reducing the burden of vertebral fracture. This work partners a cost-effective study of the phenomenon of intra-vertebral heterogeneity in a community-dwelling population with case-control and laboratory studies of the biomechanical consequences of this heterogeneity. The results will provide a widely applicable, integrated assessment of vertebral health, complete with translatable tools to set a new standard for estimation of fracture risk.