RISK ASSESSMENT OF FRACTURES DURING BIPHOSPHATE TX BY ULTRASOUND WITH BQ1-H2

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目及 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 骨质疏松症是一个主要的医学问题，临床上表现为以最小创伤发生的骨骼骨折（以下称为非创伤性骨折）。由于骨密度与骨折率呈负相关，因此骨密度已被用于定义骨质疏松症，其中低于正常峰值的约75%的值（T分数<-2.5）被称为骨质疏松症，即使在没有骨折的情况下。 然而，骨密度本身并不能预测骨折的风险。一些骨密度正常的患者会发生非创伤性骨折，而一些骨密度低的患者则不会发生骨折。 对这一发现的一种解释是，骨“质量”有时可能与骨密度“不同步”。 因此，如果骨质量上级，一些骨密度低的受试者可能不太容易骨折。 另一方面，如果骨质差，一些骨密度高的人可能容易骨折。有一些情况与骨质量有关或导致骨质量恶化，如骨的佩吉特病、骨软化症或佝偻病、固定和地方性氟中毒。骨质量被定义为“影响骨抵抗骨折能力的特征和特性的总和”（骨强度）。 不幸的是，没有商业设备可以测量骨质量非侵入性。 骨强度只能通过力学测试直接测量。 然而，由于其破坏性和侵入性，这些方法不能应用于临床。 以前已经表明，弹性模量（描述应力和应变之间关系的参数）与骨强度相关，并可用作骨强度的预测因子。 这是使用超声速度（或其功能）作为评估骨强度的非侵入性方法的基础。 然而，可用的方法是基于透射超声，其中测量超声穿过骨组织的时间或速度。 不幸的是，其中获得的数据受器官水平的骨几何形状和密度、覆盖组织和骨髓含量的影响，因此只能部分地揭示骨质量。 本研究的目的是通过超声临界角反射仪（UCR）评估使用治疗性双膦酸盐（BP）治疗骨质疏松/骨量减少的鼻后妇女发生非创伤性骨折的风险。 UCR器械可测量骨的标准化弹性，可帮助医生评估双磷酸盐治疗期间发生非创伤性骨折的风险。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Osteoporosis is a major medical problem, clinically manifested by skeletal fractures occuring with minimum trauma (henceforth named atraumatic fractures). Because bone density is inversely correlated with the rate of skeletal fractures, bone density has been used to define osteoporosis, with a value below about 75% of normal peak value (T-score<-2.5) referred to as osteoporosis even in the absence of fractures. However, bone density alone does not predict the risk of fractures. Some patients with normal bone density develop non-traumatic fractures, and some with low bone density do not sustain fractures. One explanation for this finding is that bone "quality" may sometimes be "out of step" from bone density. Thus, some subjects with low bone density may be less susceptible to fracture, if bone quality is superior. On the other hand, some with high bone density may be susceptible to fractures if bone quality is poor. There are some conditions that are associated with or cause deterioration of bone quality, such as Paget's disease of bone, osteomalacia or rickets, immobilization, and endemic fluorosis. Bone quality is defined as the "totality of features and characteristics that influence a bone's ability to resist fractures" (bone strength). Unfortunately, there is no commercial device that can measure bone quality non-invasively. Bone strength can only be measured directly by mechanical testing. However, such methods cannot be applied clinically because of their destructive and invasive nature. It has previously been shown that modulus of elasticity (the parameter that decribes the relationship between stress and strain) correlates with and can be used as a predictor of bone strength. This is the basis for using ultrasound velocity (or its function) as a non-invasive approach of assessing bone strength. However, the available methods are based on the transmision ultrasound, wherein the time or speed of ultrasound traversing across bone tissue is measured. Unfortunately, the data obtained therein are influenced by bone geometry and density at the organ level, overlying tissue and bone marrow content, and can thus only partly reveal bone quality. The purpose of this study is to assess the risk of developing atraumatic fractures in postmenopasal women taking therapeutic bisphosphonate (BP) for osteoporosis/osteopenia by ultrasound critical angle reflectometry (UCR). The UCR device performs a measurement of normalized elasticity of bone which can be used as an aid to the physician in gauging risk for developing atraumatic fractures during bisphosphonate treatment.