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Besides cost and ease of screening, these tests also vary in accuracy. Some physicians will start with the peripheral test and only conduct the centralized test if the first screen indicates poor bone density. Peripheral machines are small and portable, and they check bone density on the periphery of your skeleton, such as finger bones or the heel. They are much cheaper but not always a good indicator of bone health in bones that are the most likely to break. Centralized bone scans involve a large X-ray machine with a movable arm that will scan different parts of your skeleton while you lie on a padded table. This machine tests bone density at your hip, lower back, and forearms to get a good measure of the strength of bones that are most likely to break in a slip or fall. Most individuals receive bone density scans to check for signs of osteoporosis. Bone density scans are often used to detect your individual risk of bone fracture and your personal chance of developing osteoporosis if you do not currently have the condition. Bone density scans can also be used to monitor the effectiveness of osteoporosis treatments.
Understand the differences between peripheral and centralized bone scans. Know the purpose of a bone density test.