Computerized determination of 3-D connectivity density in human iliac crest bone biopsies

The aim of the present study was to design a computer program for direct measurement of 3-D connectivity density in iliac crest bone sections, as used for conventional histomorphometry. We used the physical disector principle and developed an algorithm for non-linear alignment of the disector pairs. The method was applied on biopsies from 14 non-selected autopsy cases: 7 men (age range 20–84 yr) and 7 women (age range 20–86 yr). Connectivity density was measured using the ConnEulor principle. The study indicated decreases in trabecular bone mass (BV/TV, %) and connectivity density with age in women. However, connectivity density measurements and BV/TV showed no significant age-related changes in either men or women. The designed computer program aligns the disector pairs and depicts the differences between images automatically, thereby making correct, direct connectivity density measurements available for conventional bone research.