Osteoporosis is diagnosed in individuals who experience non-traumatic fractures of the spine, hip, or wrist. These fractures can occur in the setting of a fall from low heights. Some individuals fracture their hip and then fall. The process of diagnosing osteoporosis will begin with a physical exam. X-rays may also be taken to detect skeletal problems such as fractures. In the absence of a fracture, bone mineral density (BMD) can be used to diagnose osteoporosis.
Bone Mineral Density: A bone mineral density test is like an X-ray of your bones. It usually measures the density of bone at the hip, in the spine, and sometimes in the wrist. It is recommended that all women 65 and older get their bone density tested (the test is covered by Medicare). Younger women should be tested if they are at high risk of bone loss (for example, because they smoke, have a family history of osteoporosis, or use medications that promote bone loss).1,2 If you break a bone after age 50, talk to your doctor about getting a bone density test.1
The BMD test produces a measurement called a T-score, which compares an individuals bone density to optimal bone density. A negative score indicates low bone mass. The World Health Organization (WHO) defines osteoporosis as a T score < -2.5 standard deviations below the mean value of peak bone mass. Osteopenia is a BMD score between -1 and -2.5.
In addition, there are laboratory tests (using blood or urine samples) that assess the process of bone breakdown and formation as well as identify conditions that may contribute to bone loss. Testing may include: blood calcium and vitamin D levels, thyroid function, measurement of estrogen levels in women and testosterone levels in men, and measurement of follicle stimulating hormone in women to establish menopausal status.
2 Building Strong Bones: Calcium Information for Health Care Providers. National Institute of Child Health and Human Development, National Institutes of Health, U.S. Department of Health and Human Services Web site. NIH Publication No. 05-5305A. Available at http://www.nichd.nih.gov/publications/pubs/upload/NICHD_MM_HC_FS.pdf.