Accuracy of lateral dual energy X-ray absorptiometry for the determination of bone mineral content in the thoracic and lumbar spine: an in vitro study.
Lateral scanning with dual energy X-ray absorptiometry (DXA) was undertaken on 153 thoracic and lumbar vertebral bodies from nine individuals (mean age 67; range 34-92 years) to establish their bone mineral content (BMC). All specimens were subsequently de-fatted and ashed to compare ash weight with BMC of the T1 to L5 segments. Linear regression analysis indicated a higher correlation between BMC and measured ash weights for each vertebral column (range: r = 0.97-0.99), with error for all vertebrae tested showing a standard error of 0.40 g, or 10.8%. For the L2-4 segments the accuracy error was 0.50 g or 7.9%. In both cases there was a mean trend towards underestimation of ash weight. Mean BMC values of the T1 to T5 segments were similar before a progressive increase caudally. These data affirm the utility of DXA for determining bone mineral content in the vertebral column across wide ranges of age, and segmental and bone density.
Department of Radiology, Royal Perth Hospital, Western Australia.
S J
SJ
Edmondston
K P
KP
Singer
R I
RI
Price
P D
PD
Breidahl
D015502:Absorptiometry, Photon / Q000592:standards; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D015519:Bone Density; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008159:Lumbar Vertebrae / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D013904:Thoracic Vertebrae / Q000737:chemistry