DEXA Scan

Bone Density Scan
Understanding bone density is critical to our health as we age. We specialize in DEXA bone density exams to gain clear images of your bones and diagnose bone conditions.

Dual Energy X-Ray Absorptiometry, called DEXA, is a scientific way of measuring bone density. DEXA uses low-dose X-rays from different angles projected at bones in the spine, hip, or wrist. Low-dose X-ray determines the density or mass of the bone. Other names for this test are Bone Mineral Density (BMD) or Dual X-ray absorptiometry (DXA). The dose of the x-ray is so minimal that the technologist sits next to you during the entire exam.

Bone density is important for health. Our peak bone mass is usually achieved in young adults between 25-30. This peak density varies between women and men and among different ethnicities. We assume your peak bone mass by comparing your density to an extensive database, which includes women or men of similar height, weight, and ethnic groups. Therefore, there are different database references for Caucasian women compared to African American men.

What Conditions & Factors Affect Bone Density?

Medical conditions
Many medical and autoimmune conditions affect bone density, including:
Liver disease
Kidney disease
Celiac disease
Small bowel absorption issues
Rheumatoid arthritis
Hyperthyroidism
Hyperparathyroidism

Diet
Our genetics, diet, and sex hormones allow us to achieve the greatest density in our mid-twenties. After that time, the density decreases over time. We can see the most significant changes in women's density after menopause because their hormones are much lower. Men exhibit the most significant decrease in density after age 50 when testosterone decreases. Our diet and nutritional access play a substantial role in developing peak bone density and can help maintain normal bone mass. A diet rich in calcium is essential at all age levels. Foods that are rich in calcium include milk products, most vegetables, and most supplemented foods.

Aging
The average American has an adequate calcium intake until they become older. The elderly have several obstacles to overcome in meeting adequate dietary calcium intake. For example, as we age, we lose our sense of taste and have other medical problems. Medication may make it harder to maintain adequate food intake. Thus, many patients who struggle with nutrition supplement with over-the-counter calcium. We do not make our own active Vitamin 3 — either we can get enough sun exposure to allow our skin to convert the inactive to the active form, or we can consume supplemental vitamin D3. Vitamin D3 levels are not routinely tested, but for some conditions, it may be recommended, such as:

• Underlying renal
• Liver
• Small bowel absorption problems
• Or thyroid conditions

Family history
We know that family history is a significant risk factor for osteoporosis. If your first-degree relatives have been diagnosed with osteoporosis, you may be at risk. For example, if a close relative suffered an osteoporotic fracture, that is considered an even stronger indication of your future fracture risk. The opposite is also true. If your immediate family members had excellent bone density, you may too.

Hereditary factors also influence peak bone density. Your body weight and height affect the stimulation of bone cortical thickening. A thicker bone cortex is necessary to hold a heavier frame. But, low body weight is a significant risk factor for low bone density. A loss of height of greater than 1/2 inch over a one-year interval is also considered a significant risk factor. 

Prior fractures
Your history of prior fractures may influence your future risk for fracture. It depends on the circumstances that caused the fracture in the first place. If you suffered a fracture from minor trauma, your fracture might be considered a "fragility" or "insufficiency" fracture. If you had a traumatic injury such as a car accident, then this history should not be used to predict your future risk.

Other factors
Some medicines, like corticosteroids and over-treatment with thyroid supplements, can affect bone density. Smoking and excess alcohol consumption also affect bone density.

When Should I Have a Bone Density Scan?
The International Society of Bone Densitometry (ISCD) and the National Osteoporosis Foundation (NOF) recommends bone density scans to start by:

• Age 65 for most women
• Age 70 for most men of average risk

The radiologist may schedule a woman as early as age 50 for a low bone density screening since most women become menopausal after this. The radiologist uses menopausal and family history risk factors to see if she needs a DEXA test. If a woman does not take hormone replacement therapy and has a family history of osteoporosis, she may need a low bone density screening earlier. However, if a woman takes hormone replacements and doesn't have a family history of osteoporosis and other risk factors, she may be able to wait until age 65.