Osteoporosis International

, Volume 15, Issue 11, pp 847–854 | Cite as

Fundamentals and pitfalls of bone densitometry using dual-energy X-ray absorptiometry (DXA)

  • Nelson B. Watts


Measurement of bone mineral density (BMD) with central dual-energy X-ray absorptiometry (DXA) is the current “gold standard” for diagnosing osteoporosis and for monitoring patients. Errors in demographic information, improper patient positioning, incorrect scan analysis, and mistakes in interpretation can all lead to a wrong clinical decision or action. This paper reviews the fundamentals of positioning, scan analysis, and interpretation for central DXA and highlights some of the common pitfalls that may lead to erroneous results.


BMD Densitometry DXA Osteoporosis 



I thank bone density technologists Sally Moody, Angie Buettner, and Terri Schmitter, who provided comments and examples for this manuscript, and other past bone density technologists and colleagues. I have learned an extraordinary amount from my associations with ISCD. I appreciate manufacturers’ input for this paper; thanks to Ken Faulkner and Jeff Franz from GE Medical Systems Lunar, Eric von Stetten and Kevin Wilson from Hologic, and Marc Zimmer and Tom Sanchez from Norland-Cooper Surgical.


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Copyright information

© International Osteoporosis Foundation and National Osteoporosis Foundation 2004

Authors and Affiliations

  1. 1.University of Cincinnati Bone Health and Osteoporosis CenterCincinnatiUSA

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