Comparative Anthropometric Evaluation of the Subpubic Angle and Ischiopubic Index in Adult Nigerians

This study was done to determine the subpubic angle and ischiopubic index of indigenous Nigerians and compare their suitability for sexing. It involved 148 anteroposterior pelvic radiographs of adult Nigerians, within the age range of 20-65years. The x-ray films were obtained from the Radiology Department of University of Port Harcourt Teaching Hospital and Braithwaite Memorial Specialist Hospital. The measurement of subpubic angle was taken with a transparent goniometer. Pubic length and ischial length were measured from a common point at the acetabulum using the movable arms of the goniometer. Values ranged from (71-81)0 with a mean of 93.110 Standard Deviation 12.5 and Standard Error 1.384 for males while for the females, the ranged from (80-98)0 with the mean of 131.100 Standard Deviation of 15.30 and Standard Error of 1.51 the ischiopubic index ranged from (71-80)0 with the mean of (89.9)0, Standard Deviation of 7.5 and Standard Error of 1.10 for males while for the females the ranged from (81-90)0 with the mean of 110.30, Standard Deviation of 9.8 and Standard Error of 0.98. Females had wider subpubic angle and ischiopubic index than males, (P<0.05). Adding the coefficient of variance, the subpubic angle gives higher variability of deviation from the mean than the ischiopubic index. Taking or using the demarking point method: 71.74% of Nigerians males and 83.33% of Nigerians females can be sexed with subpubic angle. With the ischiopubic index 63.0% of Nigerians males and 83.33% of Nigerians females can be sexed. The schiopubic index can therefore be considered a better parameter for sexing than the subpubic angle.

Key Words: subpubic angle, ischiopubic index, pelvic, pubic length, ischial length