A quantitative study of the structure of trabecular bone in man, rhesus monkey, beagle and miniature pig.

Abstract

This paper reports a quantitative comparison of trabecular bone structures in 4 mammalian species in terms of both measured path-length distributions across the trabeculae and marrow cavities as well as structural parameters derived from the pathlength data, that is, mean path lengths, percentage bone volume and the ratio of endosteal surface to bone volume. The path-length measurements have been made by scanning radiographs of thin sections of bone using an object-plane scanning microscope. Results are given for sets of up to 9 bones of a 9-year-old child, a 44-year-old man, a beagle, a rhesus monkey and a miniature pig. Mean cavity path lengths range typically from 1200 μm in the adult man to 350 μm in the miniature pig; mean trabecular path lengths range typically from 190 μm in the child to 280 μm in the miniature pig. Percentage bone volumes are lowest in adult man (∼16%) and highest in the miniature pig (∼45%) and the ratios for surface to volume show an opposite trend. Tentative estimates of skeletal values of surface-to-volume ratio are given, namely around 190 cm2/cm3 for all species studied except the miniature pig (130 cm2/cm3). Finally, an appendix illustrates the considerable effects of structural differences on radiation dosimetry.