Bone density

[1] Bone density measurement is used in clinical medicine as an indirect indicator of osteoporosis and fracture risk.

It is measured by a procedure called densitometry, often performed in the radiology or nuclear medicine departments of hospitals or clinics.

Fractures of the legs and pelvis due to falls are a significant public health problem, especially in elderly women, leading to substantial medical costs, inability to live independently and even risk of death.

Quantitative ultrasound (QUS) has been described as a more cost-effective approach for measuring bone density, as compared to DXA.

[8] Average bone mineral density = BMC / W [g/cm2] Results are generally scored by two measures, the T-score and the Z-score.

Less than 0.5% of patients who underwent DXA-scanning were found to have a T- or Z-score of more than +4.0, often the cause of an unusually high bone mass (HBM) and associated with mild skeletal dysplasia and the inability to float in water.

It is the bone mineral density at the site when compared to the "young normal reference mean".

[12] The criteria of the World Health Organization are:[13] The Z-score for bone density is the comparison to the "age-matched normal" and is usually used in cases of severe osteoporosis.

In this setting, it is helpful to scrutinize for coexisting illnesses or treatments that may contribute to osteoporosis such as glucocorticoid therapy, hyperparathyroidism, or alcoholism.

[22] Because of the heritability of bone mineral density, family history of fractures is considered as a risk factor for osteoporosis.