*Advances in Clinical Application of Bone Mineral Density and Bone Turnover Markers DOI: http://dx.doi.org/10.5772/intechopen.109074*

by ultrasonography. It is not appropriate to apply the WHO diagnostic standard of T ≤ −2.5SD, and its sensitivity and specificity are not ideal. Trimpou\_ et al. (2019) pointed out that QUS quantitative ultrasound measurement is mainly attenuation of ultrasonic signals caused by reflection and absorption of sound waves by structures in the region of interest (including soft tissue, bone tissue, and bone marrow tissue).

QUS measurements are not only correlated with bone mineral density, but also provide information about bone stress, structure and more. It is currently mainly used for screening of osteoporotic risk populations and risk assessment of osteoporotic fractures in clinical routine. Several studies of original, review or meta-analyses settings demonstrated that heel QUS parameters are strong predictors of osteoporotic fractures [21–25]. The ultimate clinical use of heel QUS parameters to assess the fracture risk will have to be based and further validated in currently widely used approaches such as FRAX.

QUS has some advantages like simplicity, no radiation damage, high repeatability, low price, and easy handling, etc., Also, QUS can be used in children and pregnant women for primary osteoporosis screening and fragility fracture prediction. Especially in medical facilities where DXA or QCT is deficient, bone density measured by quantitative ultrasound is not true for bone mineral content. It cannot yet be used for the diagnosis of osteoporosis and the judgment of drug efficacy. At present, there is no unified QUS screening judgment standard and it can be referred to the information provided by QUS equipment manufacturers. In addition, horizontal comparison of equipment from different manufacturers cannot be carried out. If the results were suspected for osteoporosis, further DXA measurements should be performed. In conclusion, although QUS currently has recognized limitations in clinical practice, it has also been widely used, especially in the field of pediatrics, township health centers, and physical examination and screening structures. Besides, substantial progress has been made [26]. The parameters of the device for evaluating bone quality are a good supplement to DXA, and it needs to be further standardized before it can be promoted clinically [14, 27].
