Bone Density Test (DEXA Scan)

A bone density test, also called a DEXA scan (dual-energy X-ray absorptiometry), measures the strength and density of your bones. It's the most accurate way to diagnose osteoporosis and assess your risk of fractures. The test is quick, painless, and uses very low doses of radiation.

Bone density testing helps identify people at risk for fractures before they occur. Early detection allows for treatment to strengthen bones and prevent fractures. The test is especially important for older adults and those with risk factors for osteoporosis.

Bone density tests are used to:

Diagnosis:

• Diagnose osteoporosis
• Diagnose osteopenia (low bone mass)
• Assess bone health

Risk Assessment:

• Assess fracture risk
• Determine need for treatment
• Guide treatment decisions

Monitoring:

• Monitor treatment effectiveness
• Track bone density over time
• Adjust treatment as needed

Screening:

• Screen at-risk individuals
• Early detection
• Prevention

Recommended For:

• Women 65+: Routine screening
• Men 70+: Routine screening
• Postmenopausal women under 65: If risk factors
• Men 50-69: If risk factors
• Anyone with fractures: After low-trauma fracture
• Anyone on osteoporosis treatment: To monitor

Risk Factors:

• Family history of osteoporosis
• Low body weight
• Smoking
• Excessive alcohol
• Certain medications (steroids, etc.)
• Medical conditions affecting bones
• Previous fractures

Usually minimal preparation:

• You can eat and drink normally
• Take medications as usual
• Wear comfortable clothing
• Remove metal objects
• No special diet needed

Before the Test:

• Inform staff if you might be pregnant
• Tell staff about recent contrast studies
• Remove jewelry
• May need to change into gown

Important: If you've had recent contrast studies (CT with contrast, barium studies), you may need to wait before DEXA scan.

During the Test:

1. You'll lie on a padded table
2. Scanner passes over your body
3. Usually measures hip and spine
4. May measure forearm (in some cases)
5. You'll need to lie still
6. Takes about 10-20 minutes
7. Completely painless

The Process:

• No discomfort
• Low radiation (less than chest X-ray)
• Can see images on screen
• Can resume normal activities immediately

After the Test:

• No restrictions
• Can resume normal activities
• Results usually available in few days
• Doctor will discuss results

T-Score (compares to healthy young adult):

• Normal: -1.0 or higher
• Osteopenia (low bone mass): -1.0 to -2.5
• Osteoporosis: -2.5 or lower

Z-Score (compares to same age):

• Used for younger adults
• Helps determine if low for age
• Different interpretation

What Results Mean:

• Normal: Bone density is good
• Osteopenia: Lower than normal, but not osteoporosis
  • May need treatment
  • Lifestyle changes important
• Osteoporosis: Significantly low bone density
  • Treatment usually recommended
  • Higher fracture risk

Fracture Risk Assessment:

• Results combined with other factors
• Age, previous fractures, etc.
• Determines overall fracture risk
• Guides treatment decisions

• Results indicating osteoporosis or osteopenia
• Need to discuss treatment
• Questions about results
• Need for follow-up testing
• Concerns about bone health

• Review results with doctor
• Discuss treatment if needed
• Schedule follow-up testing
• Continue monitoring as recommended

If Osteoporosis or Osteopenia:

• Medications: May be recommended
• Calcium and vitamin D: Supplements if needed
• Exercise: Weight-bearing and strength training
• Lifestyle changes: Don't smoke, limit alcohol
• Fall prevention: Important to prevent fractures

Monitoring:

• Repeat test in 1-2 years (if on treatment)
• May be more frequent initially
• Less frequent once stable
• Doctor will recommend schedule

Maintain Bone Health:

• Adequate calcium: Throughout life
• Adequate vitamin D: Helps absorb calcium
• Weight-bearing exercise: Strengthens bones
• Strength training: Builds bone and muscle
• Don't smoke: Smoking weakens bones
• Limit alcohol: Excessive alcohol weakens bones
• Regular screening: If at risk

If you have osteoporosis, usually every 1-2 years to monitor treatment. For screening, it depends on your age and risk factors. Your doctor will recommend.

No. It's completely painless. You just lie on a table while the scanner passes over you. There's no discomfort.

You can reduce risk by getting adequate calcium and vitamin D, exercising regularly, not smoking, and limiting alcohol. However, some factors (like genetics and age) can't be changed.

If you have osteopenia or osteoporosis, your doctor will discuss treatment options. This may include medications, supplements, exercise, and lifestyle changes. Early treatment can help prevent fractures.

No. The radiation dose is very low—much less than a chest X-ray. The benefits of detecting and treating osteoporosis far outweigh the minimal risk.