Branching pattern of the internal iliac artery accompanied by a venous anastomosis: rare vascular variations.

The ability to navigate the complex and often deceptive branching patterns of the internal iliac artery can be decisive in planning and performing surgeries within the lesser pelvis. The following case report presents a peculiar quadruple division of the internal iliac artery, accompanied by a venous anastomotic structure. Apart from the posterior and anterior trunks, the superior vesicle and iliolumbar arteries arose independently from the internal iliac artery. The division was surrounded by a venous oval, compressing certain branches and potentially complicating surgical access. Due to the uncommon course of the internal iliac artery and the presence of the anastomosis, a possible nerve root compression has been identified. Both clinical significance and classification method of the case are discussed. Knowledge of this anatomical variation is valuable for both diagnosis and surgery, especially within the specialties of urology, gynaecology and general surgery.