THE QUANTITATIVE ANATOMY OF THE ILIAC VESSELS AND THEIR RELATION TO ANTERIOR LUMBOSACRAL APPROACH

Forty embalmed cadavers (24 men and 16 women) were obtained to evaluat e the anatomic features of iliac vessels with respect to the anterior approach to the lumbosacral junction. Through a midline longitudinal i ncision over the linea aspera and retraction of the intraperitoneal co ntents, exposure of the abdominal aorta, inferior vena cava, and commo n iliac vessels was done. Direct measurements regarding the relations of these greater vessels to the sacral promontory were then performed. . The results showed the average width of the trigone, measured betwee n the medial edges of the left common iliac vein and the right common iliac artery, was 55.9 mm for male and 55.3 mm for female subjects, re spectively. The average height of the trigone, measured from its apex to the sacral promontory, was 36.9 mm for male and 35.2 mm for female subjects separately. The width of the uncovered left common iliac vein averaged 7.2 mm for male and 6.3 mm for female subjects, respectively , with a range of 3-11 mm for both male and female specimens. One shou ld be always aware of the medially placed left common iliac vein and a n approach medial to the right common iliac artery to the L5-S1 disk i s recommended if anterior surgery is desired.