FATIQUE OF BONE RELATIONSHIPS TO EXERCISE

这个项目旨在更全面地了解疲劳 失败，因为它发生在骨和在关系， 运动方案对骨的力学和几何参数的影响 以及骨骼对这些运动项目的生物反应。 以来 疲劳性骨折和疲劳性损伤经常发生， 研究人员认为，个人锻炼计划可以开始， 预防和/或治疗骨骼疲劳损伤。 作者建议使用 马作为一个自发的模型疲劳失败，并测试 假设高应变运动导致骨骼硬度降低， 就像在体外一样。 对这种高应变的生物反应 在年轻人中，是针对改变惯性特性的。 以允许骨重建来重建骨的结构。 的 作者提出利用图像重建骨内骨折损伤 分析技术，以允许2平面重建。 测量 体内骨应变将在疲劳失效之前和之后完成。 将使用骨标签检查骨建模和重建， 钙化组织学 将在体内监测骨刚度的变化 使用应变计仪器。 使用4点法进行体外测量 将进行弯曲试验，并与预测的测量值进行比较， 材料和惯性特性的计算机断层扫描数据， 正常骨和那些经受高应变循环疲劳的骨。

This project is directed at a more complete understanding of fatigue failure as it occurs in bone and at the relationships that different exercise regimens have on the mechanical and geometric parameters of bone and the biological reaction of bone to these exercise programs. Since fatigue fractures and fatigue injury occur so frequently it is the hope of the investigators that individual exercise programs could be started to prevent and/or treat fatigue injuries of bone. The authors propose to use the horse as a spontaneous model of fatigue failure and to test the hypothesis that high strain exercise caused decreased stiffness in bone in vivo much as it does in vitro. The biological reaction to this high strain in young individuals is directed at changing the inertial properties of the bone to allow bone remodeling to reconstitute the bone's architecture. The authors propose to reconstruct the fracture injury in bone using image analyses techniques to allow for 2-plane reconstructions. Measurement of in vivo bone strain will be accomplished before and after fatigue failure. Bone modeling and remodeling will be examined using bone labels and calcified histology. Changes in bone stiffness will be monitored in vivo using strain gage instrumentation. In vitro measurements using 4-point bending tests will be made and compared to predicted measurements using data from computed tomography scans of material and inertial properties in normal bones and in those subjected to high strain cyclic fatigue.