Computed tomography differentiation of compact and cancellous bone tissue in short and sesamoid bones

Selecting the most suitable skeletal remains for genetic analysis is challenging due to the variable DNA yield across different bone types and within individual bones. Compact bone typically preserves DNA longer, whereas cancellous bones, such as those in the hands and feet, often contain higher DNA quantities. This study aimed to incorporate dual-source computed tomography (DSCT), a technique frequently utilized for assessing bone density in living subjects, into targeted DNA sampling for dry, skeletonized remains by mapping compact and cancellous regions within six small skeletal elements.

A total of 137 bones were analysed using an imaging protocol specifically adapted to highlight the skeletal structure of small bones. This tailored protocol involved meticulous calibration of imaging parameters. Anatomical landmarks for six distinct elements were identified, and regions of interest were selected for bone density measurement in Hounsfield units (HU).

Among 461 assessed regions, 312 (68%) were classified as compact bone, and 149 (32%) as cancellous bone. Given the abnormal distribution of data, statistical differences were evaluated using 95% confidence intervals, with significance indicated by non-overlapping intervals. The analysis revealed statistically significant differences between compact and cancellous bone, as well as within each type across different bones.

DSCT proved effective in mapping the internal structure of six small skeletal elements in dry, skeletonized remains, underscoring significant intra-bone variability in density. The findings illustrate DSCT's substantial potential for enhancing DNA sampling in forensic and paleogenetic studies, setting the stage for future research advancements.