Age-related changes in proximal femoral strength in men and women

描述(由申请人提供)：髋部骨折发病率随年龄增长的指数增长不能用与年龄相关的面积减少来解释！骨密度(ABMD)或跌倒风险随年龄增加而增加。最近的研究概述了与年龄相关的髋部结构变化，这些变化似乎会导致脆性增加，但这可能不会反映在骨密度测量中。我们建议研究衰老对股骨近端结构和强度的影响，并将这些措施与髋部骨折风险联系起来。为了实现这一目标，我们将使用定量计算机断层扫描(QCT)进行两项研究：一项是纵向研究，旨在检查股骨近端几何和强度随年龄的变化；另一项是前瞻性研究，将这些特性与髋部骨折的发生联系起来。分析方法将包括从高分辨率QCT扫描中对髋关节进行结构分析，以及在模拟单腿站姿和向一侧坠落的负荷条件下估计髋关节强度的患者特有的有限元建模(FEM)。我们的纵向队列将是从年龄基因/环境-雷克雅未克(AGES-R)研究的5000名老年受试者中挑选出的500名患者的子集。在前瞻性骨折研究中，将使用AGES-R骨折登记来确定在基线扫描的受试者中哪些人持续髋部骨折。这些受试者的扫描结果将与一组性别和年龄匹配的对照组一起进行分析。在这项研究中，我们期望获得关于股骨近端的结构特征和强度如何随年龄变化以及它们如何导致骨折风险的影响的临床相关信息。

DESCRIPTION (provided by applicant): The exponential increase in hip fracture incidence with age cannot be explained either by the age-related decrease in area! bone mineral density (aBMD) or by the increase of fall risk with age. Recent studies have outlined age-related changes in hip structure that appear to result in increased fragility but that may not be reflected in bone density measurements. We propose to examine the effect of aging on proximal femoral structure and strength and to relate these measures to hip fracture risk. To accomplish this end, we will carry out two studies using quantitative computed tomography (QCT): a longitudinal study to examine age-related changes in proximal femoral geometry and strength and a prospective study relating these properties to incident hip fracture. The analytical methods will include structural analysis of the hip from high resolution QCT scans and patient specific finite element modeling (FEM) to estimate hip strength in loading conditions simulating a single-legged stance and a fall to the side. Our longitudinal cohort will be a subset of 500 patients selected from the 5000 elderly subjects in the Age Gene/Environment -Reykjavik (AGES-R) study. In the prospective fracture study the AGES-R fracture registry will be employed to determine which of the subjects scanned at baseline have sustained fracture of the hip. The scans of these subjects will be analyzed along with a set of gender and age-matched controls. In this study, we expect to derive clinically relevant information regarding the effect regarding how the structural characteristics of the proximal femur and its strength change with age and how they contribute to fracture risk.