What is a bone density examination?
A bone density examination is the only examination that will diagnose osteoporosis before its signs and symptoms become visible and before any bone fractures occur. With the help of a bone density test, your doctor will know more about the density and health of your bones, as well as their chance of breaking.
DXA stands for dual energy x-ray absorptiometry. This test uses a machine to measure the density of your bones. Usually, the bones of the hip, spine and sometimes even other bones are measured.
Who should have a bone density examination?
Bone density tests will tell you about the density of your bones, the presence of low bone density, also known as osteopenia, or even the presence of osteoporosis. The lower your bone density is, the greater are your chances for bone fractures due to minor trauma or no trauma at all.
Doctors use bone density tests to:
- Determine the density of your bones and the presence or not of osteoporosis
- Predict the chances of bone fractures
- Find out if the osteoporosis treatment is working or not
- See if the health of your bones is getting better and if the bone density is getting better or not, etc.
The bone density examination is usually recommended for:
- Women older than 65 years old
- Men older than 70 years old
- Women or men older than 50 years old who have a broken bone
- Women in menopause
Types of bone density tests
Central DXA – helps measure the bone density of the hip and spine. When the density of these two bones can’t be measured, then the density of the radius bone in the forearm is necessary.
The bone density of the hip and spine are measured for several reasons. First, everyone suffering from osteoporosis have a greater chance of fracturing these two bones, more than all the other bones in the human body. However, no bone is excluded from osteoporosis or fractures due to osteoporosis. Another reason is that fractures of the hip and spine are more serious than any other fractures bone, leading to serious health problems, including a longer recovery time, severe pain and even disability.
A bone density test usually lasts no longer than 15 minutes. This test is painless and not invasive at all. The person who is getting the examination is usually fully dressed, with no need to get undressed. However, no buttons and zippers should be in the area to be scanned. The levels of radiation while having a central DXA examination are very low.
When repeating the bone density tests in order to track the effectiveness of the treatment and the progression of the disease, it is better to have all the tests performed at the same examination center and with the same equipment.
Screening tests – also known as peripheral examination tests, measure the bone density in the lower arm, wrist, heel, or fingers. Different types of screening tests are available:
- pQCT – peripheral quantitative computed tomography
- QUS – quantitative ultrasound
- pDXA – peripheral dual energy x-ray absorptiometry.
How often should you have a Bone density examination?
People diagnosed with osteoporosis should have a bone density examination every one or two years.
Understanding T – score
The results of bone density examination are reported using T-score. T-score shows how much the bone density is higher or lower when compared to the bone density of a healthy 30-year-old adult.
T-score of -1 or above
T-score lower than -1 and greater than -2.5
T-score of -2.5 or lower
T-score of -2.5 or lower, and presence of at least one fragility fracture