Abstract:

Objective　To investigate the shape, distribution and variation of abnormal obturator artery and vein in the pelvic wall, and to measure the length of the segment of obturator artery in the pelvic cavity, in order to provide a reliable anatomical reference of etiology to the strange bleeding around the area.  Methods　There were 37 specimens of adult corpses fixed by the formaldehyde solution the pelvic dissection. According to the obturator artery classification method, these specimens were investigated and classified. The length of the segment of the obturator artery in the pelvic cavity, and the external diameter of it at the origin and at the obturator foramen, and the distance between the obturator foramen and the midpoint of the line connecting anterosuperior iliac spine and the pubic symphysis were explored.　Results　In these 37 specimens, the occurrence rate of abnormal obturator arteries was 18.92%. A common trunk of abnormal obturator arteries and inferior epigastric artery, length of which was（1.57±0.12）cm, originated from the external iliac artery. The length of the abnormal obturator artery was（4.05±0.49）cm, and the external diameter of it at its origin and at the obturation foramen was（2.52±0.87）mm and（2.14±0.72）mm, respectively.  The average distance between the obturator foramen and the midpoint of the line connecting anterosuperior iliac spine and the pubic symphysis was（3.63±1.29）cm.　Conclusion　The obturator artery is relatively thicker and longer in the pelvis, and has a high variation rate. Abnormal obturator arteries originate from inferior epigastric artery, and then bypasses or crosses, and vertically accesses into obturator foramen.  It is due to the special characteristics and distribution of obturator arteries, the surgeon should pay attention to its existence in inguinal surgery and pelvic fracture fixation operation, or even in oncotherapy and clearance of lymph nodes. In addition, it is better for learning about the obturator area in advance by proper usage of angiography and to apply the lateral rectus approach in the abdominal surgery. Besides, minimally invasive surgery might be another choice.

Key words: Abnormal obturator artery, 　Obturator arterial classification, 　Inguinal surgery, 　Pelvic fracture