Why are some bone density tests done in the heel or wrist and some at the spine or hip?
Any bone density test can be useful, but the bone measured and the preferred method depend on how the results of the test are going to be used. Heel or wrist bone density measurements are usually done with special portable machines, and are generally more available and less expensive than spine or hip measurements. Because osteoporosis is usually generalized throughout the skeleton, a simple measurement of bone density in the heel or wrist helps to determine if a person has low bone density relative to what they might have had when they were younger. These methods give a better indication of overall skeletal status in women over age 65 than for women early after menopause. For younger women, a measurement at the spine is the most sensitive way to determine if they have osteoporosis. Also, because the spine changes fastest with therapy or with low estrogen levels, it is usually the best site to measure for women who are starting therapy, or those who might want to delay taking hormone o
