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Medical Wiki

DXA / DEXA

A low-dose X-ray method used to estimate bone mineral density, usually at the hip and spine.

What it is

DXA estimates bone mineral density using low-dose X-rays. Reports usually include BMD plus T-score or Z-score where appropriate.[1,2]

Why it matters

It is a common way to document bone density and fracture-risk context, but it is not the whole definition of bone strength.[1]

What it affects

  • DXA often measures hip and spine because those sites are common fracture sites in osteoporosis.[1]
  • Some DXA systems can also perform vertebral fracture assessment, a low-dose spine image used to look for vertebral compression fractures.[2]

Interpretation traps

  • Machine, site, positioning, artifacts, degenerative change, and body size can affect interpretation.[3]

Related conditions

Osteoporosis and fragility fractureLow bone mass / osteopenia