Recent studies have explored error introduced through rib segmentation, which suggest possible overestimation in cross-sectional area of human rib computational models due to the resolution of full-body CT scans. Additionally, there is a need to explore age effects on rib response through simulation. In this study, we observe the effects of varying enclosed area, age-related properties, and shell thickness scheme through simulation to gauge the effectiveness of methods of translating geometry and measured material properties of bone to computational models.

A computational model of the right 6 th rib was isolated and adjusted for 128 test models (8 area adjustments x 8 cortical materials x 2 shell thickness projections). Regression equations for age-related cortical properties were taken from recent literature. The cortical surface was projected inward from the baseline model to reduce enclosed area. A constant velocity of 0.5 mm/ms was applied at the anterior end. The posterior end was pinned.

Six dependent variables were measured. Differences were observed between groups in all independent variables. Age effects and area reduction were significant in stiffness, displacement at fracture, peak force, force at yield, and energy absorbed. Area reduction was also significant in displacement at yield. The highest R 2 was found in the linear model for stiffness. The study suggests that overestimation of the enclosed area and accounting for age through age-related properties will affect the mechanical response of rib models.