Relationship of bone quality, muscle performance and body composition in osteopenic women, high performance athletes and young adults with eating disorders & changes in bone quality measured with 3D HR-pQCTafter vibration training in osteopenic women

骨微结构和骨密度(BMD)是骨质量的重要决定因素，也是骨折风险的相应预测因素。目前评估骨质量的临床标准是用双能X射线骨密度仪(DXA)测量面骨密度；然而，这种二维测量不评估骨微结构的细节。新开发的高分辨率外周定量计算机断层扫描(HR-pQCT)提供了在特定对象的基础上评估活体骨骼微结构的机会。此外，来自HR-pQCT的3D数据可以合并到有限元建模中，以直接估计受试者特定的骨强度。这项新技术将应用于四项不同的研究。一项筛查研究将调查绝经后妇女的HR-pQCT骨微结构、DXA骨密度、肌肉性能和身体成分之间的关系。振动训练是一种很有前途的提高绝经后妇女骨密度的训练方法。在为期12个月的纵向研究中，我们将通过HR-pQCT、肌肉功能和aBMD来观察振动训练对骨质量的影响。类似的方法将被用来调查青少年和年轻人的骨骼质量和肌肉功能，他们i)被诊断出患有进食障碍或ii)是精英运动员。这个年龄段的人特别感兴趣，因为生长过程中的骨积累被认为是晚年骨骼健康的重要决定因素。营养不良以及在这一关键时期高水平的锻炼也会影响骨量的增加。基于这些观察，整个项目的长期目标是在临床研究中建立HR-pQCT作为监测骨骼健康的工具，并更好地了解不同年龄组和极端条件下(如营养不良和高性能训练)骨微结构对骨强度的贡献以及骨质量和肌肉性能之间的关系。

Bone microarchitecture and bone mineral density (BMD) are important determinants of bone quality and corresponding predictors of fracture risk. The current clinical standard for assessing bone quality is areal BMD measured with dual-energy X-ray absorptiometry (DXA); however, this 2 dimensional measure does not assess detailed aspects of bone microarchitecture. Newly developed high-resolution peripheral quantitative computed tomography (HR-pQCT) provides the opportunity to assess bone microarchitecture in vivo on a subject-specific basis. Further, 3D data from HR-pQCT can be incorporated into FE modeling to directly estimate subject-specific bone strength. This novel technique will be applied to four different studies. A screening study will investigate relations between bone microarchitecture by HR-pQCT, aBMD by DXA, muscle performance and body composition in postmenopausal women. Vibration training is a promising training method for enhancing BMD in postmenopausal women. In a 12 month longitudinal study we will investigate the effect of vibration training on bone quality by HR-pQCT, muscle function and aBMD. Similar methods will be used to investigate bone quality and muscle function in adolescents and young adults who i) have been diagnosed with an eating disorder or ii) are elite athletes. This age group is specifically of interest as bone accrual during growth is considered an important determinant of bone health later in life. Malnutrition as well has high levels of exercise during this critical period can affect bone mass accrual. Based on these observations, the long-term purpose of the overall project is to establish HR-pQCT as a tool for monitoring bone health in clinical research and to better understand the contribution of bone microarchitecture to bone strength and the relation between bone quality and muscle performance in different age groups and under extreme conditions such as malnutrition and high performance training.