What does a Bone Mineral Density (BMD) Test Indicate?
What is a Bone Mineral Density Test?
A bone mineral density test is conducted in order to establish whether you have osteoporosis or not. Osteoporosis is a disease that makes the bones highly weak and fragile, susceptible to breakage. What used to happen in the past when science and medicine hadn’t broken boundaries and realms of discoveries is that osteoporosis could only be detected once an individual had broken a certain bone. However, now thanks to medicinal advances, a bone mineral density test has been designed which can detect for osteoporosis.
What a bone mineral density test does is, measure how much of calcium and other essential minerals are packed in a particular bone segment. The bones that a bone density test is administered on usually include those in the forearm, the spine and the hip.
Why and When a Test may be performed
A doctor will recommend you a bone mineral density test for one of the following reasons:
- In order to identify any possible decreases in the density of bones well before you break one.
- In order to check how much of a risk you are at of fractures.
- In case you have experienced broken bones already, to check the possibility of osteoporosis.
- In order to monitor and oversee the treatment of osteoporosis.
When it comes to osteoporosis, it is known to be a disease more common in older women. However, men can also suffer at the hands of fragile bones. Regardless of what sex or age you may be, a doctor can possibly recommend you a bone mineral density test if you fall in the following categories:
A loss of Height
A doctor may recommend you a bone mineral density test if you have experienced a compression fracture in your spine. An individual may lose as much as 1.6 inches of height over a compression fracture, with osteoporosis being one of its major causes.
Another reason when a doctor may prescribe a bone mineral density test is if you have experienced a fragility fracture. A fragility fracture occurs when your bones have become so weak that they can break easily with even a strong cough or a sneeze.
Individuals who have undergone a bone marrow or an organ transplant are at a higher risk of developing osteoporosis. In order to be on the safe side, the doctor may recommend you a test any way.
There are certain medications such as steroids which can be quite interfering with the bone building process, potentially causing osteoporosis.
Risks Involved in a Bone Mineral Density Test
The bone mineral density test is subjected to certain limitations. Some of these limitations include the following:
Discrepancies in Methods of Testing
There are certain central devices that can be used to carry out the tests and some peripheral devices as well which can perform the task. The central devices are more accurate but more costly too and measure bone density in the spinal and hip bones, whereas the peripheral devices measure bone density pertaining to the heel, finger and forearm bones.
A lot of insurance plans do not include bone mineral density tests. For details, ask you insurance provider.
Lack of Diagnosis
A bone mineral density test will only tell you where the density of your bones stands, not what the cause is. In order to diagnose the cause, you need a rather comprehensive medical evaluation and testing.
What do the Results Mean?
The results of a bone density test are represented as either a T-score or a Z-score. A T-score describes you bone density in comparison to that of younger healthier females. The Z-score on the other hand, describes your bone density in comparison to that of other people who belong to the same age, gender and race as you. With either score, a negative number represents thinner bones, with the more negative the number, the thinner your bones. Your T-score is said to be normal if it is within a range of -1.0 and above, whereas a T-score showing numbers between -1 and -2.5 displays the onset of osteopenia or bone loss, and a score that lies below -2.5 translates into osteoporosis.