DEXA Scan (Bone Density)
A low-dose X-ray scan that measures bone density to diagnose osteoporosis.
Quick Summary
To check for osteoporosis and fracture risk.
Bone mineral density at the hip and spine (T-score).
Avoid calcium supplements for 24 hours before; wear clothes without metal.
Overview
DEXA uses very little radiation.
Results are given as T-scores compared with young adults.
What It Measures
T-score
Bone density compared with young adults.
Z-score
Compared with people your age.
How It's Performed
- 01
Position
Lie on the table.
- 02
Scan
An arm passes over you; lie still for a few minutes.
- 03
Afterwards
Return to normal.
Reference Ranges
Note: Normal ranges vary by laboratory. Consult your report for the specific reference used.
| Parameter | Typical Range (Adult) | Units |
|---|---|---|
| T-score (normal) | -1.0 or above | SD |
| Osteopenia | Between -1.0 and -2.5 | SD |
| Osteoporosis | -2.5 or below | SD |
Interpreting Results & Next Steps
Discuss with Doctor
Your doctor will explain the report and what happens next.
If values are Low:
A T-score of -2.5 or below means osteoporosis.
Sources and further reading
Last updated 21 October 2026. For more detail, see these trusted health organisations.
- Bone Density Scan(opens in a new tab) · MedlinePlus, US National Library of Medicine
- Bone density scan (DEXA scan)(opens in a new tab) · NHS