You can’t see or feel osteoporosis, so how do you know if you have it? A simple, painless bone density test can give you the answer by measuring how strong your bones are. Get the details on the most common test, known as the DEXA scan, and learn what it can tell you.

The DEXA Scan   Print This Page

DEXA or DXA stands for “Dual Energy X-ray Absorptiometry,” which is a type of bone density technology. The DEXA machine takes a picture of your bones and calculates their density. Physicians commonly choose DEXA because it uses a low level of radiation (about the same as you would get on a flight from New York to Los Angeles), but detects low levels of bone loss much better than a simple X-ray. After your first scan, you should get one every one to two years to measure changes in your bone density. DEXA scans come in two types, the p-DEXA and the central DEXA:  p-DEXA The “p” stands for “peripheral.” This scan measures bones on the body’s periphery—meaning areas away from the center of the body—such as the heel, wrist, or finger. This type of bone density test is often offered at malls and health fairs. However, p-DEXA results should not be used for diagnosis or tracking progress from year to year. These tests are good screening tools and can indicate whether or not you are at high risk and should get a central DEXA scan. Central DEXA The central DEXA measures bone density in the center of the body—in the spine and hip. People are most likely to experience low bone density in these areas, and they are where low bone density is most dangerous and debilitating. These scans can provide an accurate diagnosis and method of tracking your progress from year to year.

Do You Need a DEXA Scan?   Print This Page

Medicare has established guidelines that recommend DEXA scans for certain people: estrogen-deficient women at clinical risk for osteoporosis; individuals with vertebral abnormalities; individuals receiving long-term glucocorticoid (steroid) therapy; individuals with primary hyperparathyroidism; and individuals being monitored to assess the response of osteoporosis therapies approved by the Food and Drug Administration (FDA). The National Osteoporosis Foundation recommends bone density testing for: all women over age 65; and all women under the age of 65 who have one or more risk factors for osteoporosis in addition to menopause. If you are a man, a premenopausal female, or someone else who does not fit into any of the listed categories, you may still be able to get a DEXA scan if you feel you are at high risk for osteoporosis. Be sure to discuss your risk factors with your physician.

The Scan Step by Step   Print This Page

The central DEXA scan is a painless noninvasive procedure. Here’s how it works in most cases: First, you should talk with your primary care physician and, if you are a woman, your gynecologist. Tell them about your concerns and risk factors for osteoporosis, then request a DEXA scan. When you go for a scan, you will meet a technologist, who will help you lie down on an examination platform. You may have to lie down in a certain position to ensure accurate measurements. An image of the bone to be measured (typically the hip or spine) will appear on the technologist’s computer. He or she will use the computer to place lines or boxes around the areas to be measured. The computer will then provide information about the density of that bone. At this point, your part of the scan is done. The technologist will provide a printout of the scan to a physician who is certified to read and interpret the results. This report will then be sent to your physician who will discuss the results with you.

Cost   Print This Page

Medicare may cover the cost of your bone density test if you are a woman over 65 and you qualify. Medicare will definitely cover the cost of p-DEXA or central DEXA scans for: estrogen-deficient women at clinical risk for osteoporosis; individuals with vertebral abnormalities; individuals receiving long-term glucocorticoid (steroid) therapy; individuals with primary hyperparathyroidism; and individuals being monitored to assess the response of osteoporosis therapies approved by the Food and Drug Administration (FDA). If you pay for a DEXA scan out of your own pocket, you should expect to pay $160 to $175. Many insurance companies will pay for your DEXA if your physician orders the test and you have many risk factors. Be sure to check with your insurance company to make sure you are covered.

The Quality of Your Scan   Print This Page

The DEXA scan procedure may look simple to you, but it is actually very complex. A correctly positioned and analyzed scan is crucial, because it provides the most accurate, most reliable results—results that can greatly impact your care and treatment for osteoporosis. You can make sure you get a quality scan by asking these questions: Does the technologist have ISCD training? If you clicked on the link titled “The Scan Step by Step,” you know that the technologist must position you correctly on the examination platform, then carefully position lines or boxes on the computer to take a measurement. It sounds easy, but performing the procedure accurately takes great skill. Your technologist should be properly trained and supervised. You’ll know the technologist is well trained if he or she has had ISCD training. ISCD stands for “International Society for Clinical Densitometry,” an organization of professionals that expertly trains and certifies both technologists and physicians. The physician who reads and interprets your scan should also be ISCD-trained. Does the technologist do precision testing? Quality technologists regularly test their skills with precision testing. During this test, the technologist makes two completely separate measurements of a volunteer’s bone density. The separate scans test the ability of the technologist to correctly position the patient and the computer boxes. The two tests should show the same results for the volunteer’s bone density. You should also ask your doctor if the DEXA machine is properly maintained—and if it is possible to have all your DEXA scans done on the same machine and by the same technologist. Since most people get DEXA scans every one to two years, using the same machine and the same technologist will give you the best picture of your progress.

The Results of Your Scan   Print This Page

Physicians typically measure two areas—the spine and hip—and then compare your actual bone density to the density your bones should be to resist breaking (which is the bone density of a 30-year-old). The result is a measurement called a “T-score.” Both the p-DEXA and central DEXA use a “T-score” to indicate your level of bone density but the results are used differently. Your physician will use the T-score and a skilled analysis of your scan to make an accurate diagnosis. Note: You might see a Z-score on your report, but it is not a proper number to use for diagnosis.