Quantitative assessment of the sternal rib end morphology and implications for its application in aging human remains.

Intercostal and age differences in the sternal rib end morphology of documented female skeletons from Spitalfields and St. Bride's are examined. The morphology was captured using three-dimensional morphometrics and the statistical analyses employed included parametric and nonparametric MANOVA, discriminant analysis, and multilinear regressions. It was found that the quantified morphology of the sternal rib end was statistically significantly different between rib four and all other ribs except for the third one and that the morphological characteristics of all ribs varied with age. However, due to the inherent variability in sternal rib end morphology, nonstatistically significant results were obtained among the various age groups and neither disciminant nor multilinear regression analysis could be used for the estimation of the age of an individual based on digitized coordinates of the sternal rib end of individuals of known age, raising some concern as to the rigorousness of the fourth rib aging method.