American Journal of Roentgenology, Vol 161, 621-627, Copyright © 1993 by American Roentgen Ray Society
Calcaneus as a site for assessment of bone mineral density: evaluation in cadavers and healthy volunteers
M Yamada, M Ito, K Hayashi and T Nakamura
Department of Radiology, Nagasaki University School of Dentistry, Japan.
OBJECTIVE. The value of calcaneal dual-energy X-ray absorptiometry for
monitoring changes in bone mineral density has not yet been established.
Accordingly, the focus of this study was to determine the usefulness of the
calcaneus as the site for bone mineral density measurement with dual-energy
X-ray absorptiometry. SUBJECTS AND METHODS. Dual-energy X-ray
absorptiometry of the calcaneus was performed in 19 specimens derived from
11 cadavers and 337 healthy volunteers to assess accuracy, in vivo
precision, and age-related changes in bone mineral density. We also
compared calcaneal bone mineral density determined by dual-energy X-ray
absorptiometry with lumbar spine bone mineral density determined by
dual-energy X-ray absorptiometry (L1-L4) or quantitative CT (L3). RESULTS.
Studies of specimens showed that dual-energy X-ray absorptiometry had an
error rate of 6%. In addition, strong correlations were found between bone
mineral content and ash weight (r = .97, p < .0001) and between bone
mineral density and ash density (r = .87, p < .0001). In vivo studies
showed moderate correlations between calcaneal bone mineral density
determined by dual-energy X-ray absorptiometry and lumbar spine bone
mineral density determined by dual-energy X-ray absorptiometry (men, r =
.77, p < .0001; women, r = .76, p < .0001) and lumbar spine bone
mineral density by quantitative CT (men, r = .68, p < .0001; women, r =
.68, p < .0001). Calcaneal bone mineral density measured by dual-energy
X-ray absorptiometry and lumbar spine bone mineral density measured by
quantitative CT continued to decrease throughout the postmenopausal period.
However, lumbar spine bone mineral density determined by dual- energy X-ray
absorptiometry did not show further decreases in subjects more than 70
years old. CONCLUSION. Taken together, these results suggest that the
calcaneus can be used as an additional site for determining bone mineral
density to assess osteopenia in patients when deformities of the spine make
quantitative CT or other methods of density measurement impossible.