DXA bone density scan
Also known as:
Bone mineral density test, DEXA
A low-dose scan that diagnoses osteoporosis and, with FRAX, estimates fracture risk.
Written and reviewed by Farhan Tahir, MD · Last reviewed
VIDEO LESSON
What it measures
DXA uses very low-dose X-rays to measure bone mineral density at the hip and spine. The T-score compares you with a young adult; the Z-score compares you with people your age.
Reading the results
• T-score -1.0 or higher: normal
• Between -1.0 and -2.5: low bone mass (osteopenia)
• -2.5 or lower: osteoporosis
• Z-scores are used for premenopausal women and younger men
Who should be screened
The USPSTF recommends screening women 65 and older and younger postmenopausal women at increased risk. Clinicians also consider DXA for people with early menopause, long-term glucocorticoids, low testosterone or prior fragility fractures.
Good to know
FRAX combines DXA with risk factors to estimate 10-year fracture probability. Repeat scans on the same machine when possible so changes are meaningful.
Key studies and references
Educational content only, written and reviewed by Farhan Tahir, MD. It does not replace individual medical advice. For sudden chest pain, trouble breathing or stroke symptoms, call 911.
AT A GLANCE
Test type
Bone & safety
Also known as
Bone mineral density test, DEXA
Reviewed by
Farhan Tahir, MD
Questions about your own care?
Dr. Tahir’s team offers consults through Youthful Medicine.
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