What is the arterial supply to the abdominal wall?

Arterial Supply to the Abdominal Wall

The arterial supply to the abdominal wall consists primarily of branches from the superior epigastric, inferior epigastric, and circumflex iliac arteries, with the deep inferior epigastric artery (DIEA) serving as the dominant blood supply to the anterior abdominal wall.

Main Arterial Sources

Superior Arterial Supply

• Superior Epigastric Artery (SEA)
  • Terminal branch of the internal thoracic (mammary) artery
  • Enters the rectus sheath at the costal margin
  • Descends between the rectus muscle and posterior rectus sheath
  • Provides perforators that pierce the rectus sheath within 4 cm of the costal margin 1
  • Forms anastomoses with the deep inferior epigastric artery above the umbilicus

Inferior Arterial Supply

• Deep Inferior Epigastric Artery (DIEA)

  • Arises from the external iliac artery just above the inguinal ligament
  • Courses upward between the rectus abdominis muscle and posterior rectus sheath
  • Provides an average of 5.4 large perforators (>0.5 mm) per abdomen 1
  • Has a dominant lateral division in 80% of cases 1
  • Highest concentration of major perforators is in the paraumbilical area, approximately 4 cm from the umbilicus 1, 2

• Superficial Inferior Epigastric Artery (SIEA)

  • Arises from the femoral artery just below the inguinal ligament
  • Supplies the skin and subcutaneous tissues of the lower abdomen
  • Forms anastomoses with perforators from the deep inferior epigastric system 3

Lateral Arterial Supply

• Deep Circumflex Iliac Artery

  • Arises from the external iliac artery
  • Runs along the iliac crest
  • Supplies the lower lateral abdominal wall

• Superficial Circumflex Iliac Artery

  • Arises from the femoral artery
  • Supplies the skin and subcutaneous tissues of the lower lateral abdomen

• Intercostal Arteries

  • Lower six intercostal arteries provide lateral cutaneous branches
  • Form anastomoses with branches of the deep epigastric system in the lateral abdominal wall 2

Vascular Territories and Anastomoses

Anastomotic Networks

• The deep inferior and superior epigastric arteries anastomose within the rectus abdominis muscle above the umbilicus through "choke vessels" 2
• Segmental branches of the deep epigastric system anastomose with terminal branches of the lower six intercostal arteries and the ascending branch of the deep circumflex iliac artery 2
• Perforating vessels from the DIEA feed into a subcutaneous vascular network that radiates from the umbilicus like the spokes of a wheel 2

Perforator Distribution

• DIEA perforators show marked variation in orientation, course, and morphology between individuals 4
• SEA perforators are more consistent in morphology and orientation, with significant perforators present within 4 cm of the costal margin 4
• The paraumbilical area contains the highest concentration of major perforators from the DIEA 2

Clinical Significance

• Understanding the vascular anatomy of the abdominal wall is crucial for:

  • Abdominal wall flap surgery (DIEP flaps)
  • Abdominoplasty procedures
  • Rectus abdominis musculocutaneous flaps
  • Surgical approaches to the abdominal wall

• The unpredictable orientation and course of DIEA perforators may account for ischemia-related morbidity observed with DIEA-based perforator flaps 4

• Preservation of SEA perforators adjacent to the costal margin during abdominoplasty can improve abdominal wall perfusion and reduce donor-site morbidity 4

• Preoperative imaging with CT angiography for mapping perforator anatomy is recommended before procedures like DIEP flap breast reconstruction 1

Important Anatomical Considerations

• The inferior epigastric artery is located midway between the pubis and anterior superior iliac spine and runs cephalad in the rectus sheath - this area should be avoided during procedures like paracentesis 5

• The left lower quadrant (2 finger breadths cephalad and 2 finger breadths medial to the anterior superior iliac spine) is the preferred location for paracentesis due to thinner abdominal wall and larger fluid pool 5

• Visible collaterals should be avoided during invasive procedures as they can be present even in the midline and present a risk for rupture 5