What are the different types of bone density tests and what are the differences between them?
There are various types of tests available, peripheral and central. The peripheral devices measure the finger or ankle, and these central devices measure the spine and hips. The peripheral devices are significantly cheaper and are easier to use; however, they are often used for screening for they do not measure the actual areas where fractures occur. This is due to the different types of bone in the body and its varying density in different areas. Central devices include the Quantitative CT (QCT) and the DXA scan (Dual Energy X-ray Absorptiometry). QCT uses a computerized tomography (CT) scanner together with computer software to determine the bone density, usually at the spine. QCT is the only commercially available technique to measure 3-dimensional bone images. It is the most sensitive scan to detect bone disease and can take into account other diseases such as arthritis that may affect the bone. A DXA scan measures the spine and often one or both hips. The test emits minimal radiat
