Bone density

Bone density, or bone mineral density, is the amount of <a href="/facts/Bone_mineral/L6LpbEYE">bone mineral</a> in <a href="/facts/Bone_tissue/pCU37jBe">bone tissue</a>. The <a href="/facts/Concept/VWB6yhQp">concept</a> is of <a href="/facts/Mass/HHdc8XmF">mass</a> of mineral per <a href="/facts/Volume/aeAXCBUd">volume</a> of bone (relating to <a href="/facts/Density/92p6hh9I">density</a> in the <a href="/facts/Physics/a7aH2y08">physics</a> sense), although <a href="/facts/Medicine/2fnp90Je">clinically</a> it is measured by proxy according to <a href="/facts/Optical_density/Rnv6VMX1">optical density</a> per square centimetre of <a href="/facts/Bone/pCU37jBe">bone</a> surface upon <a href="/facts/Medical_imaging/pL6JyJEp">imaging</a>. Bone density measurement is used in clinical medicine as an indirect indicator of <a href="/facts/Osteoporosis/xa1W00Tj">osteoporosis</a> and <a href="/facts/Fracture/nxDNAj0d">fracture</a> risk. It is measured by a procedure called <a href="/facts/Densitometry/eSkoaTNz">densitometry</a>, often performed in the <a href="/facts/Radiology/FMXvDL3u">radiology</a> or <a href="/facts/Nuclear_medicine/L9Dzjd90">nuclear medicine</a> departments of <a href="/facts/Hospital/WaryeVJd">hospitals</a> or <a href="/facts/Clinic/P6DdTJ9G">clinics</a>. The measurement is painless and non-invasive and involves low <a href="/facts/Radiation/RwMocyeq">radiation</a> exposure. Measurements are most commonly made over the <a href="/facts/Lumbar_spine/BytnlsNy">lumbar spine</a> and over the upper part of the <a href="/facts/Hip/UvnUYIfS">hip</a>. The forearm may be scanned if the hip and lumbar spine are not accessible.
There is a <a href="/facts/Statistics/DNPsKGYU">statistical</a> association between poor bone density and higher probability of fracture. Fractures of the legs and <a href="/facts/Pelvis/8Fq9z3TY">pelvis</a> due to falls are a significant <a href="/facts/Public_health/4563Kre9">public health</a> problem, especially in elderly women, leading to substantial medical costs, inability to live independently and even risk of death. Bone density measurements are used to screen people for osteoporosis risk and to identify those who might benefit from measures to improve bone strength.
In humans, bone density is generally higher in men, when taken at face value. However, as men have longer bones than women, it is necessary to factor in to account total bone size and volume. Volumetrically, women have greater bone density than men, as their bones are often not as long as men's.

Bone density open-in-new

Bone density