Objectives: This study was under taken to know the sexual differences in an adult (north Karnataka) human sacrum & thus identify a male from a female sacrum using various parameters. Materials & Methods: 254 dried completely ossified grossly normal human adult sacrum of both sex (190 male & 64 female) is taken from anatomy department of Mahadevappa Rampure Medical College, Gulbarga. Results: In the study the male sacrum showed significantly higher values for i) ventral straight length, ii) ventral curved length, iii) maximum sacral width (breadth of S1), iv) minimum width of sacrum & v) Weight, than female sacrum, while the female sacral index showed higher values when compared with that of male. Identification point & demarking point (DP) helped in sexing the sacrum with certainity. The most useful index for sex determination of sacrum in this study was sacral index.Summary & conclusion: after a detailed study & comparison of my work with others, I conclude that demarking point & identification point helped in sexing the sacrum with certainty. The most useful parameter in my study was sacral index. Continued study over a period of time in a defined area will definitely help in establishing the anthropometric standards for sexing the sacrum.

Key word : Sacrum, sexual dimorphism, parameters, sacral index.