Traumatic injuries sustained by the abdominal aorta are devastating, with mortality rates of 50% to 78%.1,2 Penetrating injuries confer the highest risk of mortality. Fortunately, aortic injuries are rare. Deree et al. documented 60 injuries over a 20-year period at a single Level 1 Trauma Center. Iliac artery injuries follow a similar pattern.
Given the location of these vessels, secondary injury to the abdominal organs (most commonly the gastrointestinal tract) must be also kept in mind when dealing with such injuries. In both blunt and penetrating injuries, there is a 20% risk of other injuries. In blunt injuries, this also includes traumatic brain injuries, spinal cord injuries, and/or skeletal fractures. Thus, the presence of a traumatic abdominal aortic or iliac arterial injury identifies a critically injured patient that demands precise and appropriate management.
The abdominal aorta is a continuation of the thoracic aorta as it traverses the diaphragm at roughly the 12th thoracic vertebra. It enters through the aortic hiatus of the diaphragm posterior to the esophagus. It runs within the retroperitoneum posterior to the parietal peritoneum. The aorta then courses along the anterior aspect of the lumbar vertebra. There are approximately 4 to 5 cm of intra-abdominal aorta prior to the celiac trunk. The second major branch is the superior mesenteric artery, arising 1 to 2 cm distal to the celiac trunk. This is followed by the left and right renal arteries and potential accessory renal branches off of the aorta. The inferior mesenteric artery then arises 3 to 4 cm proximal to the aortic bifurcation. Throughout its course, the aorta also has lumbar branches arising from its posterolateral aspect.
The aorta bifurcates into the right and left common iliac arteries at the level of the fourth lumbar vertebra along its left anterolateral aspect. The common iliac arteries have small branches to the surrounding soft tissue.
The right common iliac artery traverses for approximately 5 cm obliquely across the pelvic brim, passing inferior and superior to the psoas major muscle and inferior and lateral to the inferior vena cava and right common iliac vein. It continues until it bifurcates into the internal and external iliac arteries as the ureter crosses superiorly. The left common iliac artery is shorter at approximately 4 cm. While it also bifurcates as the ureter crosses, the left common iliac vein runs posteriorly medial to the arteries’ course (Fig. 12-1).
Aortic bifurcation and Iliac vessels in relation to iliac veins and inferior vena cava.
The internal iliac arteries course along the lateral walls of the pelvis supplying the viscera of the pelvis along with the perineum and gluteal region. They are approximately 4 cm in length coursing posteriorly prior to dividing into anterior and posterior divisions. The ...