HIP FRACTURE RISK PREDICTION BY QDR

描述(改编自申请者摘要)：与年龄相关的髋关节 骨折是一个日益严重的公共健康问题，超过28万人髋关节骨折 美国每年都会发生骨折，费用超过10美元 十亿美元。这个应用程序的长期目标是理解 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， 申请人证明骨矿物质之间有很强的相关性 密度(BMD)和断裂载荷在广泛的年龄和 装载率。他还表明，与跌倒严重程度相关的因素 (坠落方向、撞击地点和势能)产生强烈的和 对骨折风险的潜在主导影响和对某个领域的接触 不受骨密度影响的风险。解决令人困惑的问题 身体习惯和跌倒严重程度的影响，一个综合指数 有人提出，申请人称为风险因素。申请人 在一项有限的、回顾性的病例对照研究中显示，不仅是 风险因素与髋部骨折之间有很强的相关性，但 与单纯股骨骨密度相比，与髋部骨折的相关性更强。这个 申请者现在建议将这些研究扩展到几个重要的 方式。目标1将研究肌肉力量的作用，这两种力量都来自跌倒- 相关影响以及在日常生活的几个常见活动中， 从而估计可能导致以下情况的负荷的风险系数 自发性骨折。目标2将开发预测方法 应用有限元模型对股骨近端的破坏进行研究。这些 方法将被用来检验荷载条件和年龄的影响。 相关密度变化对骨折风险的影响。这些型号也将是 用于检查以下因素可能导致的骨折风险降低 双磷酸盐疗法。在目标3中，身体的混杂影响 对髋部骨折风险的习惯性将通过进行 利用软组织和匹配的股骨进行的一系列体外实验 来自已知身高和体重的捐赠者。这些发现将有助于提炼 他们对特定身体习性、性别的风险因素的估计 然后向下坠落。最后，在目标4中，风险因素将是 通过对养老院进行前瞻性研究进行检验 研究对象。在基线时，受试者的身高、体重、体重指数和 粗隆间软组织厚度将被评估以估计髋关节 跌倒(风险系数的分子)和髋骨产生的冲击力 用于估计股骨强度的矿物质密度(因子的分母 风险)。申请人假设风险因素不会 只与髋部骨折的发生率密切相关，但将是一个 比单纯的BMD更能预测髋部骨折的风险。有干预的 基于对复杂相互作用的更好理解的战略 在跌倒生物力学和骨骼脆性之间，申请者认为 人们希望，日益流行的髋部骨折在 老年人的人数可以大大减少。

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.