internal iliac artery branches

3 min read 16-03-2025

The internal iliac artery, also known as the hypogastric artery, is a crucial vessel supplying blood to the pelvic organs and surrounding structures. Understanding its branches is vital for clinicians, students, and anyone interested in pelvic anatomy and vascular surgery. This comprehensive guide explores the internal iliac artery's branches, their distribution, and clinical significance.

Anterior Division Branches: Nourishing the Pelvis

The anterior division of the internal iliac artery gives rise to several branches that primarily serve the pelvic viscera and abdominal wall. These branches are characterized by their relatively larger caliber and more superficial location compared to the posterior division.

Umbilical Artery & Superior Vesical Artery:

The umbilical artery, a remnant from fetal circulation, typically becomes obliterated after birth, persisting only as the medial umbilical ligament. A small portion near the bladder may remain patent, giving off the superior vesical artery, supplying the superior portion of the urinary bladder.
Variations exist; in some individuals, a significant portion of the umbilical artery remains patent, contributing to bladder perfusion.

Inferior Vesical Artery:

The inferior vesical artery is a critical branch supplying the inferior portion of the urinary bladder.
In females, its branches may also contribute to the vaginal blood supply.

Middle Rectal Artery:

The middle rectal artery provides blood to the rectum and anal canal. Its contribution to rectal perfusion is important to consider in surgical procedures involving this region.

Internal Pudendal Artery:

The internal pudendal artery is a significant branch supplying the external genitalia, perineum, and muscles of the pelvic floor. It's a key artery for urologists and gynecologists to understand.
It branches into the inferior rectal artery, perineal artery, and dorsal artery of the penis/clitoris.

Obturator Artery:

The obturator artery passes through the obturator canal to supply the medial compartment of the thigh. This artery is clinically relevant due to its potential for variations in its origin and course, sometimes arising from the internal iliac artery directly and sometimes from the inferior epigastric artery, an anastomosis that may be crucial for collateral circulation.
It has muscular branches (to the adductors), and an acetabular branch to the hip joint.

Uterine Artery (Females):

Exclusively found in females, the uterine artery is a major branch supplying the uterus, fallopian tubes, and vagina. Its importance in obstetrics and gynecology cannot be overstated.
Understanding its course and branching pattern is crucial for surgical procedures like hysterectomies.

Posterior Division Branches: Supporting the Buttocks and Back

The posterior division branches are smaller and typically supply the gluteal region, the sacrum, and the posterior abdominal wall.

Iliolumbar Artery:

The iliolumbar artery ascends to supply the psoas major muscle, quadratus lumborum, and parts of the iliac fossa.

Lateral Sacral Arteries:

The lateral sacral arteries descend to supply the sacrum, the piriformis muscle, and the muscles of the posterior abdominal wall. They provide blood flow to the sacral nerves and can be surgically significant in sacral surgeries.

Superior Gluteal Artery:

The superior gluteal artery, one of the largest branches of the internal iliac artery, passes out of the pelvis superior to the piriformis muscle. This artery supplies the gluteal muscles and the skin of the buttock. It's crucial in surgeries involving the gluteal region.

Inferior Gluteal Artery:

The inferior gluteal artery exits the pelvis inferior to the piriformis muscle. It supplies the gluteus maximus and other deep muscles of the buttock.

Clinical Significance of Internal Iliac Artery Branches

Knowledge of the internal iliac artery branches is crucial in various clinical settings:

Pelvic surgery: Understanding the arterial supply is vital for minimizing complications during hysterectomies, prostatectomies, and other pelvic procedures. Collateral circulation needs to be considered.
Trauma: Injury to the internal iliac artery can lead to significant blood loss, requiring immediate intervention.
Embolization: Interventional radiology utilizes embolization techniques to stop bleeding from pelvic vessels in cases of trauma or tumors. Precise knowledge of the arteries is essential for effective embolization.
Diagnostic imaging: Angiography, CT angiography, and MRI can visualize the internal iliac artery and its branches, aiding in diagnosis and treatment planning.

Conclusion

The internal iliac artery and its branches play a critical role in supplying blood to the pelvic organs and surrounding structures. A thorough understanding of these branches' anatomy, distribution, and clinical relevance is essential for healthcare professionals involved in pelvic surgery, trauma care, and interventional radiology. This knowledge improves surgical planning, minimizes complications, and ultimately leads to better patient outcomes. Further exploration into the individual branches and their variations within the population is recommended for a comprehensive understanding of pelvic vascular anatomy.