Background: Sex determination in mutilated and fragmentary remains is an important exercise in forensic practice. Present study was conducted to establish sex using foramen magnum morphometry on skulls from autopsied bodies. Materials & Methods: A total of 230 skulls (146 males and 84 females) were studied to measure antero-posterior diameter (length) and transverse diameter (breadth) of foramen magnum. Area of foramen magnum was calculated and Sectioning point analysis was performed. Results: Mean length, breadth and area of foramen magnum in male were 36.40 mm, 32.93 mm and 939.50 mm2 respectively, whereas the mean length, breadth and area in females were 31.62 mm, 28.32 mm and 700.5 mm respectively. Thus, measurements in males were significantly higher as compared to females. Sectioning points for length, breadth and area were 34.01 mm, 30.62 mm and 820 mm2 respectively. Sectioning Point analysis showed the accuracy of sex determination is more with area of foramen magnum followed by length and breadth of foramen magnum. Conclusion: The foramen magnum morphometry can be an important tool in sex differentiation.

Key words: Skull; foramen magnum; sex determination; south Indian.