OsteoAge: Bone Density Testing

What is a Bone Densitometry?

Also called a DEXA Scan (dual energy x-ray absoptiometry), this test is a fast, painless, non-invasive, low dose x-ray procedure used to measure the calcium content of your bone, also known as bone mineral density (BMD). DEXA is used to diagnose osteoporosis, a gradual loss of calcium, which causes your bones to become thinner and more likely to break. The results of DEXA help your physician assess your OsteoAge, or the relative biological age of your bones compared to other subjects your age.

PhysioAge Medical Group utilizes the state-of-the-art GE Lunar DUO Densitometer with a pencil-beam x-ray (pictured below). Total radiation exposure is about 9% of that of a standard chest x-ray.

Who needs a Bone Densitometry exam?

While the disease affects both men and women, 80% of those affected are women. In fact, 22 million American women are affected by osteoporosis. Women have a higher risk for osteoporosis than men because women often have smaller, thinner frames. In addition, menopause causes women to produce less estrogen, a hormone that helps protect them against bone loss; 20% of bone mass can be lost in the 5-7 years following menopause.

Factors that may add to the risk of osteoporosis include:

Female
Caucasian or Asian
Advanced age (>65 years)
History of bone fracture
Small, thin frame
Family history of osteoporosis
Post-menopausal, including early or surgically induced menopause
Low-calcium diet
Lack of exercise
Eating disorders
Abnormal absence of menstrual periods
Certain medicines (such as steroids and anticonvulsants)
Alcohol or tobacco use

Preparing for your DEXA Scan
There are no special preparations for a DEXA Scan. However, you will want to keep in mind the following before coming for your test:

Do not take your calcium supplements on the morning of your appointment. Solid calcium can appear similar to bone if it remains undissolved in the digestive tract.
Inform our office in advance if you have had a barium procedure or have been given an injection for a CT Scan or Radioisotope Scan.
You may eat and drink normally

What Should I Expect?
You will be asked to remove all clothing with metallic objects (zippers, snaps, etc.) that would obstruct the scan path. During your test you will lie on a padded exam table. The technician will adjust your position for the area that will be scanned.

There will be three scans in all: one spine and two hips. For the spine you will lie flat on your back. For the hips you will have your feet in a brace, which rotates your hips and knees inward.

You will need to remain still for a short period of time. The lumbar region scan takes approximately 3 minutes, while a scan of your hips will take approximately two minutes each.

What do the results mean?
Your bone mineral density is given in two ways: “young normal” or T-Score and “aged-matched” or Z-Score.

T-Score
The T-Score compares your BMD (bone mineral density) to that of a healthy, young adult of the same sex. This value determines your fracture risk.

Z-Score
The Z-Score compares your BMD to what would be the expected BMD of someone your age and body size.

Your doctor will interpret your T-Score results for you.

According to the World Health Organization, a T-Score at or above a –1 is normal and has a low risk of fracture. A T-Score between –1 and –2.5 is considered Osteopenia with a moderate risk of fracture. A T-Score at or below –2.5 is considered Osteoporosis with a high fracture risk.

All new patients receive a Bone Density scan as part of their initial biomarker testing. The need for follow-up testing will be determined by your physician.