All About Bone Density Scan/Test
A bone density test is a type of test to determine if you have osteoporosis(bone loss than usual) or some other bone issues like cancer, breaking bones etc. It use X-rays to measure how many grams of calcium and other bone minerals are stored into a segment of bone. The bones that are most commonly tested are in the spine, hip and sometimes the forearm. It is also called DEXA test.
Why do you need a bone density test?
If you have a broken bones, of course you need to this test. Other issues like joint pain, back pain requires this test too. But most osteoporosis patients probably never knew such thing until things got worse. Because osteoporosis is a very slow process and it won’t have any clear signs until it is already formed. If you have any osteoporosis symptoms such as lost height, sore joint, or 35 years or older, especially women, we recommend they have bone density test routinely.
In case you want to know more about osteoporosis symptoms, here is a separate article. Osteoporosis (bone loss) symptoms
How bone density test is done?
Bone density tests are usually done on bones that are most likely to break because of osteoporosis, including:
- Lower spine bones (lumbar vertebrae)
- The narrow neck of your thighbone (femur), next to your hip joint
- Bones in your forearm
If you have your bone density test done at a hospital, it’ll probably be done on a central device, where you lie on a padded platform while a mechanical arm passes over your body. The amount of radiation you’re exposed to is very low, much less than the amount emitted during a chest X-ray. The test usually takes about 10 to 30 minutes.
A small, portable machine can measure bone density in the bones at the far ends of your skeleton, such as those in your finger, wrist or heel. The instruments used for these tests are called peripheral devices, and are often found in pharmacies. Tests of peripheral bone density are less expensive than are tests done on central devices.
Because bone density can vary from one location in your body to another, a measurement taken at your heel usually isn’t as accurate a predictor of fracture risk as a measurement taken at your spine or hip. Consequently, if your test on a peripheral device is positive, your doctor might recommend a follow-up scan at your spine or hip to confirm your diagnosis.
How to read result?
Your bone density test normally will have two numbers, one is called T-score. one is called Z-score. Your Dr will tell you exactly what it means and what you might need to pay attention.
Here we only explain the most common T-score:
|T-score||What your score means|
|-1 and above||Your bone density is considered normal.|
|Between -1 and -2.5||Your score is a sign of osteopenia, a condition in which bone density is below normal and may lead to osteoporosis.|
|-2.5 and below||Your bone density indicates you likely have osteoporosis.|
Here are more related readings:
Osteoporosis Dietary Supplement Recommendations:
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