Fracture healing assessment by real-time and noninvasive Raman spectorscopy

描述(申请人提供)：骨折破坏骨骼的基本新陈代谢和机械功能，从而威胁健康和生活质量。骨折愈合试图恢复骨骼的形状、功能和材料特性。生物矿化被认为在达到稳定形式之前经历了一系列的瞬时阶段，在体外无脊椎动物和牙本质中观察到了这种过程，最近Morris团队在体内发现了胎鼠组织的这种过程。然而，骨组织矿化背后的生化机制，特别是在骨折愈合过程中，仍然不是很清楚。虽然骨折骨痂矿化被认为类似于生长板矿化，但在骨折修复过程中瞬时矿物相的出现并没有被实时检测到。这项研究的假设是：(1)骨折愈合包括从无序相到瞬变相到最终稳定相的矿物质转化，这一机制与骨龄和发育阶段相似；(2)骨折愈合过程中可以无创地监测骨折骨痂的生化成分，这些测量可以预测骨痂材料的质量。 为了验证这些假说，我们将对雄性野生型小鼠的股骨中段骨折骨痂进行矿化动力学研究。拉曼光谱将在不同年龄的小鼠骨折修复的早期阶段的24小时内检测动力学。接下来，将研究骨骼成熟的雄性野生型小鼠骨折愈合过程中骨痂中的骨基质和矿物质特性。非侵入性拉曼光谱观察到的生化特性将与几何和机械特性相关联，以评估该技术表征骨折骨痂完整性的能力。这项拟议的研究将提供有关骨折愈合过程中组织矿化进展的独特信息，并将评估非侵入性拉曼光谱系统监测愈合过程的能力。总体而言，这些实验的目标是深入了解骨折愈合矿化的机制，并提供一种临床成像和分析工具，以无创地评估骨折部位，而不考虑年龄。这种类型的信息在检测和纠正异常愈合方面可能是非常有价值的，因此可能有助于制定促进成功骨修复的策略。

DESCRIPTION (provided by applicant): Bone fractures disrupt essential metabolic and mechanical functions of the skeleton and thus threaten health and quality of life. Fracture healing attempts to restore the shape, function, and material properties of bone. Biomineralization is thought to proceed through a sequence of transient phases before reaching a stable form, a progression that has been observed in vitro for invertebrates and dentin and recently was discovered in vivo for fetal murine tissue by the Morris group. However, the biochemical mechanisms behind bone tissue mineralization, particularly during fracture healing, are still not well understood. While fracture callus mineralization is thought to be similar to growth plate mineralization, the occurrence of transient mineral phases during fracture repair have not been examined in real time. The hypotheses for this study are that (1) fracture healing includes a mineral transformation from a disordered phase through a transient phase to a final stable phase, and this mechanism is similar regardless of skeletal age and stage of development; and (2) biochemical composition of the fracture callus can be monitored noninvasively throughout the healing process, and these measurements are predictive of callus material quality. To test the hypotheses, mineralization kinetics will be followed for the fracture callus at the femoral middiaphysis of male wild type mice. Raman spectroscopy will examine the kinetics over a 24-hour period in the early stages of fracture repair for mice of different ages. Next, bone matrix and mineral properties will be studied in the fracture callus throughout healing in skeletally mature male wild type mice. The biochemical properties observed by noninvasive Raman spectroscopy will be correlated with geometric and mechanical properties to assess the ability of this technique to characterize the fracture callus integrity. The proposed study will provide unique information about the progression of tissue mineralization during fracture healing and will assess the ability of a noninvasive Raman spectroscopic system to monitor the healing process. Overall, the goals of these experiments are to gain insights into the mechanisms of fracture healing mineralization and to provide a clinical imaging and analysis tool to assess the fracture site noninvasively, regardless of age. This type of information could be invaluable in the detection and correction of abnormal healing and thus may be useful for developing strategies to promote successful bone repair.