Prajith Thekke Madathil
BACKGROUND Establishing identity from skeletal remains is a real challenge in the field of Forensic Medicine. Determination of sex is statistically the most important critical step as it immediately excludes approximately half the population. Even though the bones showing sexual dimorphism such as skull and pelvis were studied extensively. Studies on sternum in this aspect were not much and most of them revealed racial and regional variations in the indices. So, the present study is an attempt to find out the significant traits for determination of sex if any, among population of north Kerala. MATERIALS AND METHODS This study was conducted on 100 sterna collected from identified corpses brought for medicolegal autopsy at Department of Forensic Medicine, Govt. Medical College, Calicut. Specimen sterna were collected from consecutive cases of male and female corpses of age above 25 years. Clear data regarding identity including age in completed years, was verified from next of kin. RESULTS The predictability of sexing from morphometrical assessment of manubrium was considerably low due to most of them (more than 90%) falling in the zone of overlap. The length of the mesosternum could sex 28% of population by binary regression using SPSS analysis. In case of combined midline length (of manubrium and mesosternum), the mean for male was 135.29mm and 121.44mm for female. 74% of the population showed the length to be in an overlap zone and could sex 16% specimens only using SPSS binary regression. The values observed in the present study were much lower than that for North Indian sterna, with a mean difference of 13.85mm. Only 17 out of 50 (34%) of female sterna had a combined midline length equal to or more than 126mm. Only 9 out of 50 (18%) of male sterna had a length equal to or below 126mm. CONCLUSION Among various parameters which showed lesser overlapping, the most common was combined midline length- 74%. If a cut of length of 126mm was chosen (midpoint of zone of overlapping,) 41 out of 50 male sterna (82%) and 32 out of 50 female sterna (64%) could be sexed. Over all sternum is a poor indicator regarding sexing if considered alone.
