Bone density scan (DEXA for osteoporosis) Diagnostic Imaging

A bone density scan, also called a DEXA or DXA scan, uses low-dose X-rays to measure how much mineral is in your bones.

Bone density scan (DEXA for osteoporosis) procedure illustration

Overview

A bone density scan, also called a DEXA or DXA scan, uses low-dose X-rays to measure how much mineral is in your bones. It most often checks the hip and spine. Clinicians use DEXA to help diagnose osteoporosis, estimate fracture risk, and monitor bone density over time. The test is quick, noninvasive, and does not require needles or anesthesia.

Overview Preparation Clinical Info Recovery FAQ References

Also known as: DEXA scan, DXA scan, Bone densitometry, Dual-energy X-ray absorptiometry

Recovery
Same day
Return to Work
Same day

Preparation & Next Steps

Everything you need to know before and after your procedure

Before Care

  • Bring a photo ID, insurance card, and any prior bone density reports for comparison
  • Wear comfortable clothing without metal zippers, snaps, belts, or underwire if possible
  • Remove jewelry and items from pockets before the scan
  • If instructed, avoid calcium supplements for 24 hours before the exam
  • Tell the technologist if you might be pregnant
  • Tell the staff about any recent barium studies, nuclear medicine tests, or CT/MRI with contrast
  • List your current medicines, especially steroids or osteoporosis medicines
  • Plan to arrive a bit early for check-in and screening questions
  • Ask the facility which body areas will be scanned (hip, spine, or forearm) and how long it will take

After Care

  • Resume normal eating, drinking, and activities immediately after the scan
  • Review how and when you will receive your report and images
  • Learn what your T-score and Z-score mean and keep a copy of the results
  • Store the report for future comparisons at the same or different facility
  • Ask about typical intervals for repeat testing based on your situation and guidelines
  • Tell your clinician about any new falls, height loss, or fractures after the scan
  • Confirm whether additional imaging, labs, or referrals are planned
  • Contact the imaging center if you notice errors in your name, date of birth, or scan date on the report

Clinical Information

Important medical details about this procedure

Indications

  • Screening for osteoporosis in people at higher risk
  • Evaluating low-trauma or fragility fractures
  • Monitoring bone density during or after osteoporosis treatment
  • Long-term use of steroids like prednisone
  • Conditions linked to bone loss (for example, hyperparathyroidism or malabsorption)
  • Postmenopausal status with risk factors
  • Height loss or suspected vertebral fracture

Alternatives

  • Quantitative computed tomography (QCT) of the spine or hip
  • Peripheral tests such as heel ultrasound or forearm DXA
  • Clinical fracture risk tools (for example, FRAX) using history and measurements
  • Review of prior imaging for vertebral fracture assessment when available

Risks

  • Very low radiation exposure
  • Results can vary between machines and over time
  • Positioning or motion may affect accuracy
  • Metal or surgical hardware near the scan area can interfere with measurements

Contraindications

  • Known or possible pregnancy
  • Recent barium study or imaging with contrast or tracer that can affect results
  • Inability to lie still on the table for several minutes
  • Body size or weight above the scanner table limit

Recovery Timeline

What to expect during your recovery

There is no medical recovery period after a DEXA scan. Most people return to normal activities right away.

Typical Range

Same day

Return to Work

Same day

Recovery Milestones

Day 0

Resume normal daily activities

Day 0–1

Review preliminary instructions from the imaging center or portal

Day 1–14

Review the official report and discuss next steps at a routine visit

Frequently Asked Questions

Common questions and expert answers about this procedure

What does a DEXA scan measure?

It measures bone mineral density, which helps show if bones are normal, low (osteopenia), or in the osteoporosis range.

Which bones are usually scanned?

Most exams measure the hip and lumbar spine. The forearm may be scanned if the hip or spine cannot be measured.

How long does the test take?

The scan itself often takes about 10 to 20 minutes, with total visit time depending on check-in and positioning.

How much radiation is used?

DEXA uses very low-dose X-rays. The exposure is typically lower than many standard X-ray exams.

What are T-scores and Z-scores?

A T-score compares your bone density to that of a healthy young adult. A Z-score compares you to people your age and sex.

Can implants or prior spine surgery affect results?

Metal hardware, hip replacements, or spinal changes can affect measurements. The technologist may scan another site if needed.

How often is DEXA repeated?

Intervals vary by guidelines and clinical factors. Many people are retested every 1 to 2 years when monitoring change.

What if I recently had a barium study or nuclear medicine test?

These can interfere with a DEXA image. Facilities often recommend waiting a period of time before scheduling DEXA.