A study of the homogeneity of the trabecular bone mineral density in the calcaneus.

In the past our laboratory has reported a method of measuring trabecular bone mineral density (TBMD) in the calcaneus in vivo by using the coherent-to-Compton scattering ratio. In the present work the distribution of TBMD in the calcaneus has been studied, and the reproducibility of this technique in vivo has been determined. It is found that although the TBMD may vary within the calcaneus, a region exists over which the variation in density is not large. This region coincides with the midportion of the heel and is the site chosen for the measurement of TBMD by the coherent-to-Compton scattering ratio technique. The reproducibility of this technique in vivo has been determined to be 3.4%.