Forensic Age Estimation of the Sternum in the Malaysian Malay Population by Geometric Morphometric Analysis

Abstract

Introduction: Virtual morphometric age assessment on the body of sternum and manubrium bones among the Malay population in Malaysia has never been conducted previously. Materials and methods: In this retrospective study, the morphological structures of the sternum and manubrium of 124 healthy individuals between the ages of 2 and 50 years old were analysed utilising geometric morphometrics. 37 landmark points were digitised on the body of the sternum and manubrium using IDAV software and the results were analysed in MorphoJ. Principal Component Analysis (PCA), Procrustes ANOVA, Discriminant Function Analysis (DFA) and regression on the centroid size to age were carried out to determine if sex and age affected the body of sternum morphology. Results: Geometric morphometric analysis indicates that age is the best method of classifying both body of sternum and manubrium. Regression analysis shows an increase in the size of the bones and reaching adult size before 20 years of age. Sexing is possible with DFA (cross-validation) and the effect is seen more on the sternum compared to the manubrium at 59.7%. Conclusion: The regression figure is useful as it provides a qualitative summary of the sternum and manubrium growth at different age ranges. This figure should be useful for forensic pathologists and medical practitioners who need to predict the age of the sternum body and manubrium by visual assessment.