TMSS Medical College Journal

Background: Study of skeletal remains of the unknown decomposed body plays a vital role for establishing the identity of the subject. Sexual dimorphism is found in the different parameters of sacra, which varies within and between the worldwide populations. Materials and Methods: A cross-sectional descriptive study was conducted among 100 dry adult human sacra from January 2023 to June 2024, Department of Anatomy, TMSS Medical College and Shaheed Ziaur Rahman Medical College, Bogura. Data were collected by using a pre-designed questionnaire prepared for the study. Sex determination was done by using discriminant function analysis (DFA) and found 43 male and 57 female sacra Results: The straight length and ventral curved length of sacrum was found to be significantly greater in male than females (p<0.000). The breadth of sacra was found significantly greater in females compared to male (p=0.001). The sacral index was significantly less in male (94.45 + 4.98%) compared to females (109.84 + 8.80 %) (p<0.000). The curvature index was significantly more in male (95.00 = 4.79 %) compared to females (91.72 + 4.24 %) (p=0.000). Conclusion: This study findings can provide a baseline data for morphometric sex differences in the sacra of northern region of Bangladesh. The length of sacra and curvature index were greater in male; but the breadth of sacra and sacral index were greater in female; whereas different other morphometric parameters do not differ significantly.

Determination of the sex of the unknown decomposed body is necessary to determine age, ancestry and stature estimations. Sexual dimorphism is found in the dimensions of sacra, which differs within and between the populations. These differences allow the development of discriminant functions which reduce the subjectivity of sexual diagnosis from morphologic traits. The discriminant function is population specific and differs with race and geographical location’ The sacrum, a large triangular bone formed by fusion of five sacral vertebrae, lies in the central part of the postero-superior wall of the pelvic girdle. It supports the erect spine and provides the strength and stability of the bony pelvis to transmit the body weight and also allows considerable mobility in childbearing.’ The anterior and upper margins of the body of the first sacral vertebra bulge forward as the posterior margin of the pelvic inlet called sacral promontory, which is an important obstetric landmark used when measuring the size of the pelvis.