ABSTRACT
Morphological features, the size of the preauricular sulcus and the thickness of the ventral sacro-iliac ligament were examined in both male and females Thai cadavers pelves in which the age, the sex and the past history of pregnancy were known. The gross appearance of the preauricular sulcus in males, which was characterized by a short, narrow and shallow groove, of the sulcus in parameters obtained, including the width, depth and length when comparing the left and the right in any individual group of either male or female pelves (p>0.05). There was also no significant difference in the dimensions of the sulsuc and the thickness of the ventral sacro-iliac ligament when comparing between the male and nulliparous female (p>0.05). In contrast, the parameters of both, the size of the sulsuc and the thickness of the ligament in parous females, were significantly greater than that in males and nulliparous females. The results suggest that the size of the preauricular sulcus could be used as a reliable index for indicating the Thai parous female. The thickness of the ventral sacro-iliac ligament may be another index in addition to the size of the preauricular sulcus.