HIP FRACTURE RISK PREDICTION BY QDR

描述（改编自申请人摘要）：髋关节相关 骨折是一个不断升级的公共卫生问题，超过28万髋关节 在美国每年发生的骨折， 亿 本申请的长期目标是了解 影响髋部骨折风险的生物力学因素， 开发可用于临床的非侵入性密度测量方法 用于骨折风险预测。 在上一个资助期内， 申请人证明了骨矿物质 骨密度（BMD）和骨折负荷在很宽的年龄范围内保持不变， 装载率 他还表明，与跌倒严重程度相关的因素 (fall方向、撞击地点和势能）施加强大的 对断裂风险的潜在主导影响，并触及某一领域 风险与骨密度无关。 为了解决 身体形态和跌倒严重程度的影响，一个综合指数 被提出申请人称之为风险因素。 申请人 在一项有限的回顾性病例对照研究中， 危险因素和髋部骨折之间有很强的联系，但 与髋部骨折的相关性强于单独的股骨BMD。 的 申请人现在建议在几个重要的领域扩展这些研究。 的方式 目标1将检查肌肉力量的作用，无论是从下降- 相关的影响，并在一些常见的日常生活活动， 从而估计可能导致 自发性骨折 目标2将开发预测方法 股骨近端失效的有限元模型。 这些 方法将被用来检查加载条件和年龄的影响， 相关密度变化对骨折风险的影响。 这些车型也将在 用于检查由以下因素引起的骨折风险的潜在降低 二磷酸盐治疗 在目标3中，身体的混杂影响 髋关节骨折风险的习惯将通过进行一项 使用软组织和匹配股骨的一系列体外实验 捐献者的血液 这些发现将有助于完善 他们对特定体型、性别、 和下落方向。 最后，在目标4中，风险因素将是 通过对老年疗养院进行前瞻性研究进行测试 科目 基线时，受试者的身高、体重、体重指数和 将评估转子软组织厚度，以估计髋关节 跌倒（风险因素分子）和髋骨撞击力 用于估计股骨强度的矿物质密度（因子的分母 的风险）。 申请人假设风险因素不会 仅与髋部骨折发生率密切相关，但将是一个 比单独BMD更好的预测髋部骨折风险。 通过干预 基于对复杂的相互作用的更好理解的战略 申请人认为， 有希望，越来越多的流行性髋部骨折， 老年人可以大大减少。

DESCRIPTION (Adapted from the applicant's Abstract): Age-related hip fractures are an escalating public health problem, with over 280,000 hip fractures occurring each year in the US and costs in excess of $10 billion. The long-term objectives of this application are to understand the biomechanical factors that influence hip fracture risk, and to develop non-invasive densitometric measures that can be used clinically for fracture risk prediction. During the previous funding period, the applicant demonstrated that strong associations between bone mineral density (BMD) and fracture load hold over a wide range of age and loading rates. He has also shown that factors related to fall severity (fall direction, impact site, and potential energy) exert a strong and potentially dominant influence on fracture risk and touch on a domain of risk independent of bone density. To address the confounding influences of body habitus and fall severity, a composite index has been proposed that the applicant calls the factor of risk. The applicant has shown, in a limited, retrospective, case-control study, not only a strong association between the factor of risk and hip fracture, but a stronger association with hip fracture than femoral BMD alone. The applicant now proposes to extend these studies in several important ways. Aim 1 will examine the role of muscle forces, both from fall- related impact and during several common activities of daily living, thereby estimating the factor of risk for loads that could cause spontaneous fractures. Aim 2 will develop methods for predicting failure of the proximal femur using finite element models. These methods wull be used to examine the effect of loading conditions and age- related density changes on fracture risk. These models will also be used to examine potential reductions in fracture risk induced by bisphosphonate therapy. In Aim 3, the confounding influence of body habitus on hip fracture risk will be characterized by conducting a series of ex vivo experiments using soft tissues and matching femurs from donors of known height and weight. The findings will help refine their estimates of the factor of risk for a given body habitus, gender and fall direction. Finally, in Aim 4, the factor of risk will be tested by conducting a prospective study of elderly nursing home subjects. At baseline, subject height, weight, body mass index and trochanteric soft tissue thickness will be assessed to estimate the hip impact forces from a fall (numerator of factor of risk) and hip bone mineral density to estimate femoral strength (the denominator of factor of risk). The applicant hypothesizes that the factor of risk will not only associate strongly with hip fracture incidence, but will be a better predictor of hip fracture risk than BMD alone. With intervention strategies based on an improved understanding of the complex interplay between fall biomechanics and bone fragility, the applicant believes there is hope that the growing epidemic of hip fractures among the elderly can be substantially abated.