Internal Iliac Artery Branching Pattern Variation

Textbooks emphasize the number and order of arteries that arise from the anterior and posterior divisions of the internal iliac artery. However, common trunks for internal iliac artery branches occur with varying frequency, which may lead to a decrease in the confidence level of an identification in cases of unexpected branching patterns. We present a cadaveric study on variations in the branching pattern of the iliac arteries. All cadavers (N = 47: 28 females, 19 males, 94 hemipelves) were donated to the UNTHSC Willed Body Program. We report frequencies of shared trunks between branches of internal iliac and compare them with previous studies. The rate at which internal pudendal and inferior gluteal share a trunk differs statistically between studies: 31.9% of cases in our study, and 60.9% of cases reported by Braithwaite (1952) (p = 0.0001). Other branches such as the middle rectal and internal pudendal shared a trunk in 24.5% of cases; middle rectal and inferior gluteal shared a trunk in 7.4% of cases. These values are similar to the findings reported by Parsons & Keith (1897). Students are encouraged to memorize the order of arterial branching patterns, but shared trunks, as well as their varying incidence across studies, emphasize the need for students to identify arteries based on target organ rather than memorizing a branching pattern. Research supported by Department of Integrative Physiology & Anatomy.