Years ago, the only time osteoporosis could be detected was after you broke a bone and had an x-ray. By then your bones could already be weak.
Today, a bone mineral density test or BMD exam (also called a bone densitometry test), can determine if you have osteoporosis or are at risk for this disease before you break any bones. This exam uses low-dose x-ray to measure how many grams of calcium and other bone minerals are packed into a segment of bone. The higher the mineral content, the denser the bones are and the risk of fracture is lower.
A bone mineral density (BMD) exam is not a bone scan (this exam is a Nuclear Medicine exam performed using radioisotopes).
BMD exams are easy, fast and painless. The only preparation required is to not take a calcium supplement the morning of the exam. For this exam, you will lie on a padded BMD table for a few minutes while the scanner – a mechanical arm-like device – passes over your body. It will not touch you. There is radiation emitted during this exam and the exposure during a BMD is commonly about one tenth of the amount emitted for a chest x-ray.
The exam usually takes about 20 minutes to complete. The radiologist will interpret the exam and the results will be sent to your physician within 3-5 working days.