Objective: To provide detailed information of corona mortis for ilioinguinal approach as an anterior approach to the acetabulum and pelvis. Methods: The course, branches and distribution of the vascular connection between the obturator system and the external iliac or inferior epigastric systems located over the superior pubic ramus were observed on 50 hemipelvises with intact soft tissues. Results: During the dissections, 72% of the cadaveric sides had at least one communicating vessel between the obturator system and the external iliac or inferior epigastric systems on the superior pubic ramus. The average diameter of the connecting vessel was 2.6 mm (range, 2.0- 4.2 mm). It coursed over the superior pubic ramus or iliopubic eminence vertically to enter the obturator foramen and exit the pelvis. The average distance from pubic symphysis to the vascular connections between the obturator and external iliac systems was 52 mm (range, 38-68 mm). Conclusions: Vascular connections between the obturator system and the external iliac or inferior epigastric systems were found over the superior pubic ramus with a high incidence. They are prone to damage during the ilioinguinal approach as an anterior approach to the acetabulum and pelvis. Thus, corona mortis located over the superior pubic ramus deserves great attention during the ilioinguinal approach.
