‘Bone Mineral Density test’ – you may have heard of this term. If you are wondering what this test is and why it is done, then this article will make things clear for you.
Over the years, I have come across a number of patients who complain of weakness and bone pains. Many of these are women who are in the post-menopausal stage of their lives.
As we get older, our bones naturally get a little thinner. The density of the bone is reduced. The extent to which it reduces varies from one individual to another.
The loss of bone mass and the thinning of bones makes it very susceptible to breaking and fracture. Even the slightest of trauma could lead to a fracture.
It is therefore important to ensure the bones are strong and healthy.
Bone health can be easily assessed through a bone mineral density study, also called a BMD study. Let’s take a look at this study in a little more detail.
What Is A Bone Mineral Density (BMD) Test?
A BMD test is a test used to determine the thickness and strength of the bones. It measures the quantity of calcium and other minerals in the bone that makes it strong.
When assessing the bone density, only a particular part of the bone is assessed. The commonly studies bones are the spine, forearm and hip bones.
Why Is A Bone Mineral Density Test Done?
A BMD test is performed to assess the presence of a condition called osteoporosis.
Osteoporosis is also called ‘brittle bone disease’. It is a condition where the bones have lost all their vital minerals and become thin and brittle.
So why is a bone mineral density test important?
It’s simple. If your bones are thin they can break easily.
Patients who have osteoporosis are at a high risk of developing fractures. These fractures can occur from the mildest of trauma or injury. Sometimes a sneeze can break the bones!
A BMD test may also be done to assess progress and improvement in bone health if you are taking tablets for osteoporosis.
By detecting thinning of the bones early, your doctor will be able to prescribe medicine to strengthen the bones and advise you on how to prevent injury and fractures.
When Is A Bone Density Test Advised?
You could get a bone mineral density test done as a routine if you wish to know how healthy your bones are.
However, there are a particular group of patients who will almost always require a bone density test to be done. I have listed this in the table below.
How Is The BMD Test Done?
Without going into too much detail, I would like to firstly tell you that the test is painless.
The tests that are done are called DEXA scans. A central DEXA scan measures the density of the bones using a scanner that passes over the spine and the hip. This scan is more accurate and is recommended for a detailed BMD assessment.
On the other hand, a peripheral DEXA scanner assesses bone thickness in the forearm, legs or heel. It is quicker to do this and is often done in free medical camps.
The central DEXA test is done with a large X-ray machine. The peripheral DEXA scans use a smaller machine.
If you wish to get your bone density assessed, it is better to get a central DEXA scan done.
Normal Results Of A BMD Test
When you look at a report of a BMD test, you may find 2 different terms used – T score and Z score.
The T score is more commonly used in practice. It compares the density of your bone to those of healthy young women.
The Z score is used less frequently. It compares the thickness of your bone to others individuals of the same gender, age, weight and race.
T – Score
The normal scores for the T score is more than – 1. It may be 0 or 1 or even more.
A score of less than – 1 indicates bone thinning.
– 1 to -2.4 is called osteopenia.This is the early stage of bone thinning.
> -2.5 is called osteoporosis. This is a more advanced stage.
Z – Score
A Z-score of less than -2 indicates an alternate cause for bone thinning other than age.
By evaluating your T and Z score, your doctor will be able to tell you if you have osteoporosis or not, and whether you need any treatment.
Risks Of BMD Test
The bone mineral density test requires your body to be exposed to a small amount of radiation.
However, this is a negligible amount and does not cause any side effects.
There are no serious risks associated with BMD testing.
What After The Test?
If your BMD reveals you have thin bones, then your doctor will likely prescribe vitamin D and calcium supplements. These should be taken as prescribed to keep the bones strong.
You will also be asked to exercise regularly. Walking regularly can improve the health of bones and make them stronger.
A bone mineral test is a useful test to determine how strong and thick your bones are. It is simple to perform and gives reliable results with minimal risks.
Here is a quick recap of the entire article in the form of a simple presentation –