Glossary: Peripheral Bone Density Testing

You've probably seen portable devices that determine bone mineral density at sites such as the wrist, the fingers, or the heel. Because they are small and cost less than other methods of testing bone density, these devices are frequently used for large-scale osteoporosis screenings. However, bone density varies among different skeletal sites, and bone density may be normal at one site and low at another site. Because these devices only test bone density in a specific site, they may miss indications of osteoporosis in other skeletal areas. In early postmenopausal years, bone density in the spine decreases first, and bone density at other sites does not begin to coincide until about age 70. Although these devices are considered accurate, they may not be precise enough to monitor patients undergoing treatment for osteoporosis. So, even if your have peripheral bone density is "normal," you may still need a more extensive bone density test to rule out osteoporosis.