To fully understand the effects of aging on the integrity of the normal skeleton, detailed geometric models are needed to complement material property data. The purpose of this research is to develop a predictive model for age-related changes in rib-cage geometry using the generalized Procrustes approach, an advanced method of shape analysis. This predictive model is coupled with the finite element method to isolate the effects age-related size and shape change have on the structural response of the rib cage. Using a relatively small sample set (n = 12), trends in the age-related size and shape change of the human thorax consistent with clinical observations are identified. Finite element models constructed from landmark datasets generated via the generalized Procrustes approach demonstrate a decrease with age in the energy absorbing capacity of the thorax during a blunt impact.