నైరూప్య

The Angle of the First Rib and Its Implication in Forensic Anthropology: A Morphometric Study.

Anne D Souza, Mamatha Hosapatna, Vrinda Hari Ankolekar*, and Antony Sylvan D Souza

Assessing the sex of an adult human skeleton is fundamental in forensic anthropology. The identification of skeletal remains is important for both legal and humanitarian reasons. Five distinct landmarks are formed on the first rib, head, tubercle, sternal end and groove for subclavian vein and artery. In non-anatomical position, an angle is visible between the head and the tubercle at the inferior portion of the neck. In cases where the pelvis and skull are not available or too damaged for examination, the ribs may provide an alternative method for estimating sex of an individual. The present study included 35 right and 35 left first ribs. The following measurements were taken in non-anatomical position like length from head to tubercle, height from head to surface, external length and internal length. Angle of the rib was determined using an inverse sine function, with measured height over the length. The mean and standard deviation of height and length of right side were 5.51± 3.65mm and 25.20± 4.52mm respectively and on left side 6.28± 2.81mm and 23.70± 3.39mm respectively. Unpaired t-test was used to determine the significance of means between angles of right and left side which was not statistically significant (p=0.17). On right side Pearson's correlation test showed a positive correlation between the angle and the external length and also for the internal length (r=0.8, 0.7). On left side Pearson's correlation test did not show any significant positive correlation between them (r=0.3, 0.2).The present study was an initial step in estimation of the angle which can be used for estimating sexual dimorphism. Further researches on the first rib can add to the information and help the forensic anthropologists to identify the sex of an individual.