Biomechanics of Spine Fracture

脊柱骨折的生物力学

• 批准号: 6825417
• 负责人: Tony M Keaveny
• 金额: $ 63万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-28 至 2008-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6825417
• 关键词: bioimaging /biomedical imaging; biomechanics; bone density; bone fracture; bone imaging /visualization /scanning; computed axial tomography; disease /disorder proneness /risk; human tissue; image processing; mechanical stress; osteoporosis; photon absorptiometry; physical model; postmortem; spine disorder; vertebrae

DESCRIPTION (provided by applicant): Vertebral osteoporosis is a major health concern both in the United States and worldwide, and is expected to affect substantially more people as the size of the aging population increases. Currently, the clinical gold standard for assessment of fracture risk for the spine is dual-energy x-ray absorptiometry (DXA). This two-dimensional scanning modality is limited in its ability to predict fracture risk, and improved methods of fracture risk prediction are therefore needed. Quantitative computed tomography (QCT), being a three-dimensional imaging modality, offers great promise at providing such improved measures, but the complexity of the underlying biomechanics of spine fractures undermines the ability of QCT alone to predict fracture risk. In particular, the vertebral body displays different strength properties for the different types of loads it encounters in vivo, such as compression vs. anterior bending. QCT scans, being descriptors of only the bone structure, cannot account for these different strengths. Recent advances in bone biomechanics and computational stress analysis techniques now enable us to produce patient-specific structural computer finite element models of an individual's vertebra directly from QCT scans in an almost entirely automated fashion. Ideally suited for clinical implementation, these "voxer' finite element models can provide a fracture risk prediction that overcomes the limitations associated with DXA and QCT. Through an unique multidisciplinary team of bioengineers, clinical QCT radiological experts, and epidemiologists, we plan to implement this computational modeling technique clinically and compare its performance against DXA and QCT. In particular, we will test its ability to predict fracture risk in an ongoing NIH-funded osteoporosis prospective fracture surveillance study of almost 6000 men aged over 65, for which both DXA and QCT scans are available at baseline. To ensure that our modeling technique is optimized for successful clinical usage, we will first perform a detailed biomechanical validation of the technique as applied to cadaver vertebrae for varied loading conditions, including compression and combined compression/forward bending. We will also address the role of the posterior elements, and treat the disc condition as an uncertainty variable. Our Hypothesis is that the QCT-based finite element modeling technique, being mechanistic, is better at clinical fracture risk prediction than purely densitometric techniques such as DXA and QCT. This research will provide insight into the biomechanical mechanisms of osteoporotic spine fractures by way of our cadaver studies. It will have profound clinical impact by improving substantially the ability to predict risk of vertebral fracture in the elderly. Finally, we hope this research will instigate a paradigm change in musculoskeletal imaging in which engineering mechanistic models are integrated into medical images to provide a true functional image, in this case the "biomechanical scan" of the vertebra.

描述（由申请人提供）： 椎骨骨质疏松症在美国和全球范围内都是主要的健康问题，随着老龄化人口的规模的增加，预计将影响更多的人。目前，评估脊柱断裂风险的临床金标准是双能X射线吸收率（DXA）。这种二维扫描方式的预测能力有限，因此需要改进的断裂风险预测方法。定量计算机断层扫描（QCT）是一种三维成像方式，在提供这种改进的措施方面提供了巨大的希望，但是脊柱骨折的基本生物力学的复杂性会破坏QCT单独预测断裂风险的能力。特别是，椎体在体内遇到的不同类型的载荷显示了不同的强度特性，例如压缩和前弯曲。 QCT扫描仅是骨结构的描述，无法解释这些不同的优势。骨生物力学和计算应力分析技术的最新进展现在使我们能够直接以几乎完全自动化的方式从QCT扫描中生成患者特异性的结构计算机有限元模型。这些“ Voxer的有限元模型都可以提供理想的适合临床实施，可以提供一个断裂的风险预测，以克服与DXA和QCT相关的局限性。通过独特的多学科生物工程师团队，临床QCT放射学专家的临床QCT放射学专家以及流行病学家，我们计划在临床上对其进行临床范围的效果进行访问和QCT，我们计划实施该计算模型技术，以确定其始终如一。 risk in an ongoing NIH-funded osteoporosis prospective fracture surveillance study of almost 6000 men aged over 65, for which both DXA and QCT scans are available at baseline. To ensure that our modeling technique is optimized for successful clinical usage, we will first perform a detailed biomechanical validation of the technique as applied to cadaver vertebrae for varied loading conditions, including compression and combined compression/forward弯曲。我们的假设是，基于QCT的有限元建模技术是机械性的，在临床断裂风险预测方面比纯正密度测定技术（例如DXA和QCT）更好。这项研究将通过我们的尸体研究来洞悉骨质疏松性脊柱骨折的生物力学机制。它将通过基本提高老年人椎骨骨折风险的能力来实现深远的临床影响。最后，我们希望这项研究能够激发肌肉骨骼成像的范式变化，其中工程机械模型被整合到医学图像中，以提供真正的功能图像，在这种情况下为椎骨的“生物力学扫描”。