Bone densitometry, using an advanced technology called DXA (short for dual-energy x-ray absorptiometry), safely, accurately and painlessly measures bone mineral density. Bone densitometers with an additional capability called Instant Vertebral AssessmentTM or IVA, may also produce an x-ray of the entire spine for the assessment of vertebral (spine) fractures. PIC's bone densitometer can also precisely analyze your body fat.
During a comprehensive examination with DXA, you lie comfortably still on a padded table while the DXA unit scans two or more areas, usually the fracture-prone hip and spine. Unlike typical x-ray machines, radiation exposure during bone densitometry is extremely low-less than the radiation exposure during a coast-to-coast airline flight. The entire process takes only minutes to complete, depending on the number of sites scanned. It involves no injections or invasive procedures, and you remain fully clothed. DXA is a fast, convenient and precise way to measure bone density and to help determine your risk of developing osteoporosis and future fractures.
Preparing for a bone density exam
Wear comfortable clothing without zippers or metal if possible (the metal creates a false reading). Patient gowns are also available. No special prep is necessary.
Do not schedule nuclear medicine or studies with Barium prep (like a fluoroscopy study or certain CT exams) within two days before your bone density exam as the contrast used in these tests will also cause a false reading.
Please refrain from taking any calcium supplements 24 hours before a bone density exam as this may also cause a false reading.
Results
T score - This number shows the amount of bone you have compared with a young adult of the same gender with peak bone mass. A score above -1 is considered normal. A score between -1 and -2.5 is classified as osteopenia, the first stage of bone loss. A score below -2.5 is defined as osteoporosis. The T score is used to estimate your risk of developing a fracture.
Calculate Your 10-Year Probability of Fracture with FRAX
Patients can now calculate their ten year probablility of fracture with an online tool developed by the World Health Organization called FRAX. Simply follow the instructions on the home page, beginning with a simple click of the "Calculation Tool" button to determine which country data to compare to. The next screen has you combine your weight/height to metric equivalents, and plugs the data into the 12 question form. You will need the "Femoral Neck BMD" from your graphic data results (Region = Neck, and trace across three columns to BMD [g/cm squared]) for Question 12. Also, select "Hologic" from the drop down, the scanner we use here at Providence Imaging Center (see screenshot below). The results include your BMI, and are printable for your records. They include your percentage of risk for both major osteoporotic and hip fracture.
