Geometric and harmonic study of the aging of the fourth rib.

One of the current reference methods, namely the Işcan method for estimating age at death, consists in the subjective observation of the sternal end of the fourth rib. In this study, we looked to identify the morphometric characteristics of the sternal end of the fourth rib that were most affected by aging by measuring them in an objective way. For this purpose, we collected measurements from the fourth rib tip of 414 French males and used mathematical algorithms derived from pattern recognition and signal processing to identify variables that reflect both geometric characteristics and serration patterns of the ribs. Completed analysis was carried out on the 284 ribs for which all the variables could be collected. We showed that the three least collinear variables that best explain age objectively are the postero-superior pit depth, the fine serrations of the ovoid (delineating the pit shape), and its posterior flaring. This work provides a useful basis for subsequent studies on aging and age prediction.