Bone Density Test

What is a bone density test?

A bone density test is used to determine whether a person has normal bone density, low bone density or osteoporosis. The most common form of the test is done through a dual-energy X-ray absorptiometry (DEXA) scan which is an enhanced form of x-ray technology that is used to measure the amount of bone loss. The machine produces two different beams of x-ray, one of which has higher energy than the other to measure bone density. This is the most accurate test available to determine bone density at present.
It is to be noted that a bone density test is different from the process of bone scan. A bone scan is done to detect fractures, cancer, infections and other abnormalities in the bone and needs an injection before it is done.

Why is a bone density test done?

What is the importance of bone health?

Bones form the framework of our body, supporting our movements and providing protection to the important organs. Healthy bones store vital minerals like calcium and phosphorus that keep them strong and are also needed for various other bodily functions. The more the density of the bone or the bone mass, the stronger it remains.

The bones in our body are in a continuous process of transformation, with old cells breaking down and new cells being formed. For an average person, the peak bone mass occurs around the age of 30. The better the peak level of bone mass, the more effective will you be in maintaining good bone density as you age. In case bone density levels fall below a certain point, osteoporosis can develop in the bones, resulting in brittle bones that can break easily.

What are the main causes of low bone density and Osteoporosis?

With age, we tend to lose more bone mass than the body generates, weakening the bones. Osteoporosis can generate in the body from many factors, out of which, the following can be listed as the most important causes.
– Improper Diet: A diet that lacks calcium and Vitamin D can lead to loss of bone density. Vitamin D affects the synthesis of calcium in the body and hence it should be a necessary diet component.
– Lack of Exercise: Regular exercise helps the bones to remain stronger and healthier. Lack of physical activity is a major reason for poor bone health.
– Tobacco and alcohol: Smoking causes the disruption of the calcium absorption process in the body. Alcohol consumption can also lead to increased risk of being affected by osteoporosis.
– Medicines: Certain medicines, for e.g. glucocorticoids, can lead to the loss of bone mass in the body.
Apart from the above factors, there are also a few causes that are beyond your control.
– Age: Bones mass will decrease with age, leading to a higher probability of aged people getting affected by osteoporosis.
– Gender: Women have less bone tissue than men and are more susceptible to the effects of osteoporosis.
– Genetic structure: If you have a history of osteoporosis in your family, you are at more risk. Ethnicity also plays an important role with white women and Asian women facing a greater risk from the disease.
– Bodyweight and structure: Individuals with a small body structure and those who are thin have less bone mass in their body.
– Hormonal action: Over secretion of the thyroid hormone can lead to the loss of bone mass. The drop in estrogen levels in a woman’s body after menopause is a major cause of bone loss. Lower levels of testosterone in men can also lead to low bone density.
 

How to know whether you have low bone density?

Osteoporosis does not have any particular external symptom and hence it advances undetected in most cases. Quite often it is detected when a bone breaks or fracture occurs due to an accident. If you have any one or more of the following diseases, it is important that you consult your doctor regarding your bone health.
– Cushing’s disease
– Multiple sclerosis
– Any liver or kidney-related disease.
– Arthritis

Do I need to appear for the test even if I am healthy?

As per the recommendations of the U.S. Preventive Services Task Force, it is necessary for all women at and above the age of 65 to undergo this test. Women of menopausal age and postmenopausal woman under age 65 should also undergo the test if there are risk factors. Men above the age of 70 should also undertake this test. In case you are above 50 and have broken a bone, the doctor can suggest the test.

How common are bone disorders in India?

Bone disorders such as arthritis and osteoporosis are widespread in India. It has been estimated that more than 15% of the population, i.e, over 180 million Indians suffer from arthritis.

How is a bone density test done?

In most centers, it is done through a central device that requires the patient to lie down on a padded platform, fully clothed, while a mechanical arm passes over the specified area. The test takes around 10 to 20 minutes. Based on the passage of the X-rays through your bone, an image is formed.
Some clinics also use light and portable box-like machines to calculate the bone density in the peripheral regions like fingers, wrist or heel. The cost of using such machines are low but measurements taken at the peripheral parts are not as accurate as of the ones taken from the hip or spine area. These devices make it easier for those who cannot appear for a central DEXA test due to any reason.

How to prepare for a bone density test?

Bone density test is a simple procedure and no advance preparations are needed. It is best that you avoid consuming calcium supplements 24 hours before the test. Wear loose and comfortable clothing without zippers or metal buttons and remove all metal objects like keys, money clips or change from your pockets.
If you are pregnant please inform the medical practitioner about it before the test. In case you have had an injection of barium or contrast dye for a CT scan or MRI, wait for 7 days before appearing for a central DXA. The contrast dye can interfere with the bone density test.

What is the normal range of a bone density test?

The results of a bone mineral density (BMD) test is compared with a standard value of bone mineral density of a healthy young adult and the patient is given a T-score.  T-score of +1 and −1 is considered healthy and more the value shifts below zero, the higher is the risk of osteoporosis.
The following chart indicates the bone density level definitions as specified by the WHO.

What is the cost of a bone density test in India?

The cost of a bone density test in India varies from INR 1200 to INR 5000 depending on the quality of the center and the city where it is located.

Are there any side effects of a bone density test?

This is a safe and painless test that is free from complications and deliver fast results. The magnitude of X-rays to which your body is exposed in very of very low intensity to cause any harm.

What to do if I am detected with low bone density?

If you are detected with low bone density or osteoporosis, your doctor can advise the right course of action to be taken. This may involve steps like slowing or preventing osteoporosis, maintaining a healthy bone density through the correct lifestyle, pain reduction and conducting daily life smoothly without accidents. Apart from a healthy diet and exercise, the doctor can also recommend medications as required.