Bone Mineral
Density (BMD)
Bone densitometry is a medical examination to measure bone density. In other words, it assesses the strength of the skeleton. It allows physicians to analyze the risk of osteoporotic fracture related to osteoporosis. It consist in a measure of areal bone mineral density (in g / cm ²) and not a volumetric density.
Over a lifespan, bone mineral density usually increases up to age 20-30, and then remains constant until age 40, then decreased gradually afterward. This usually affect both sexes, but the increase in bone density is higher for men. Low bone density is an excellent indicator of fracture risk.
The process for measuring bone density
The reference method for assessing the quality of the bone is now the X-ray absorptiometry. This consist in emitting photons in the direction of a bone, which partially absorb them. A photon detector is installed on the other side of the bone. The more dense the bone is, the fewer are the photons that reach the detector. We then measure what quantity of protons succeeds in passing through the bone, which provides information on bone density.

Preparation
You should not undergo examination with barium (barium enema, transit) or nuclear medicine two weeks before the exam. Do not take calcium tablet for 24 hours before the examination. Bring your slippers on exam day.