WHEN TO START BONE MINERAL DENSITY SCREENING

Bone health is an important part of your overall well-being, especially as you age. Bones support your body, allow you to move, and protect your organs from injury. They are also living, growing tissue that break down old bone and rebuild new bone through a process called resorption.

Peak bone mass is usually reached between age 25-30, but after age 50 your bones begin to break down faster than new bone is formed. It’s often around this age that your doctor may first recommend bone density screening because your bones start to lose calcium and other minerals, which in turn makes them lighter and less dense. Bones can become more fragile and likely to break.

The older you are, the more likely you are to have low bone density, sometimes called osteopenia. Low bone density can increase your chance of getting osteoporosis – a disease which makes bones more porous and brittle, and can lead to fractures, pain, and deformities.

The most accurate way to determine the density of your bones is to have a bone mineral densitometry (BMD) exam, also known as dual-energy X-ray absorptiometry (DEXA). A first (baseline) BMD exam is often taken at around age 50 and then subsequent exams may be recommended every two years.

A bone mineral densitometry exam is an X-ray scan that measures the density of minerals (such as calcium) in your bones. It is used to help determine the strength of your bone and whether you are at risk of a bone fracture or if you have osteoporosis.

WHO SHOULD GET A BONE MINERAL DENSITY EXAM?

Low bone density and osteoporosis rarely cause symptoms, which means you may not discover you have one of them until you sustain a painful fracture. This is why early detection is important, as well as being aware of your risks.

Women are at higher risk of developing osteopenia or osteoporosis due to having smaller or less dense bones than male bones. Their risk is also increased after menopause when bone loss is accelerated due to the rapid decline in estrogen levels. Because osteoporosis is more common in women than men, it’s often thought of as a women’s disease. However, men frequently get osteoporosis. According to Osteoporosis Canada, one in five men will suffer from an osteopathic fracture and men who have a major fracture, such as hip fracture, are more likely to have complications than women.

Other risk factors for bone loss include having a diet low in calcium, an inactive lifestyle, smoking, certain diseases associated with malabsorption issues and hyperparathyroidism, and taking certain medications like glucocorticosteroids.

Regular bone density testing is recommended to monitor bone loss. A BMD exam is not usually required until you are 50 years of age or older, unless you fall into a high-risk category. To determine if bone density testing is right for you, you will need to discuss your risk factors and family history with a health care practitioner.

WHAT HAPPENS DURING A BONE MINERAL DENSITY EXAM?

A bone mineral densitometry exam sends a low-dose X-ray beam through the spine, hip, or forearm. Special computer software subtracts the soft tissue information and displays the bone density measurements. Generally, the higher the mineral content, the denser the bone is, and the denser the bones are, the less likely they are to fracture.

During your BMD exam, you will need to avoid wearing clothes with buttons, metal buckles, and zippers near your spine and hip as they may interfere with the X-ray. You will be weighed and measured, then positioned on the table by the technologist. You will be asked to hold very still while the scanner moves over the area being examined. You may be scanned more than once.

Measurements must be very precise. Since measurements can vary between machines, repeat tests must be taken on the same machine, or a new baseline will be needed.

HOW IS BONE DESITY MEASURED?

If you are age 50 or older, your bone mineral density test result will be a T-score. A T-score is the difference between your bone mineral density and the average bone mineral density of a healthy young adult.

If you are younger than 50, your bone mineral density test result will be a Z-score. The Z-score is the difference between your bone mineral density and the average bone mineral density for healthy people of your age and sex.

HOW DO I GET A BONE MINERAL DENSITY EXAM?

To determine if bone density testing is right for you, you will need to discuss your risk factors and family history with a health care practitioner, who would then provide a requisition for this procedure if it’s needed. You can then call to book an appointment with our Contact Centre, and they will explain how to prepare for your exam.

Please visit bone mineral densitometry services for more information about what happens during this exam and how to prepare.

WHAT HAPPENS AFTER MY EXAM?

Once your exam is completed, your images will be reviewed by a specialized radiologist who will compile a report that is sent to your doctor within two business days, sooner for urgent requests. Mayfair Diagnostics is owned and operated by over 50 specially trained radiologists, which allows for an expert review of your imaging by the applicably trained radiologist.

Your doctor will review your images and the report from the radiologist and discuss next steps with you, such as a treatment plan or the need for further diagnostic imaging or lab tests to ensure an accurate diagnosis.

Mayfair Diagnostics has 13 locations across Calgary and one in Cochrane that offer bone mineral densitometry services.

REFERENCES

John Hopkins Medicine (2023) “Osteoporosis: What You Need to Know as You Age.” www.hopkinsmedicine.org. Accessed July 26, 2023.

National Institute of Arthritis and Musculoskeletal and Skin Diseases (2023) “Bone Mineral Density Tests: What the Numbers Mean.” www.niams.nih.gov. Accessed July 26, 2023.

OrthoInfo (2023) “Healthy Bones at Every Age.” www.orthoinfo.aaos.org. Accessed July 26, 2023.

Osteoporosis Canada (2023) “Men and Osteoporosis.” www.osteoporosis.ca. Accessed July 26, 2023.

Osteoporosis Canada (2023) “Facts and Stats.” www.osteoporosis.ca, Accessed July 26, 2023.