What is the arterial supply and venous drainage of the abdominal wall?

Arterial Supply and Venous Drainage of the Abdominal Wall

The arterial supply of the abdominal wall is primarily derived from the deep inferior epigastric artery, which is more significant than the superior epigastric artery in supplying the skin of the anterior abdominal wall. 1

Arterial Supply

Superior Arterial Supply

• Superior Epigastric Artery (SEA)

  • Origin: Terminal branch of the internal thoracic (mammary) artery
  • Course: Enters the rectus sheath behind the rectus abdominis muscle
  • Distribution: Supplies the upper portion of the rectus abdominis muscle and overlying skin
  • Perforators: Relatively consistent in morphology and orientation 2
    • Pierces the rectus sheath within 4 cm of the costal margin
    • Present bilaterally in most individuals
    • Extensive territories oriented toward the umbilicus

• Lower Intercostal Arteries (9th-11th)

  • Origin: Posterior intercostal arteries from the thoracic aorta
  • Course: Travel along the inferior border of the corresponding ribs
  • Distribution: Supply the lateral and anterior abdominal wall muscles
  • Anastomoses: Connect with branches of the superior and deep inferior epigastric arteries

• Subcostal Artery (12th)

  • Origin: Directly from the thoracic aorta
  • Course: Follows the inferior border of the 12th rib
  • Distribution: Supplies the upper lateral abdominal wall

Inferior Arterial Supply

• Deep Inferior Epigastric Artery (DIEA)

  • Origin: External iliac artery just before it passes beneath the inguinal ligament
  • Course: Travels upward between the rectus abdominis muscle and posterior rectus sheath
  • Divisions: Divides into medial and lateral branches 3
    • Lateral division is dominant in 80% of cases
    • Provides more numerous and consistent perforators
  • Perforators: Average of 5.4 large perforators (>0.5 mm) per abdomen 3
    • Highest concentration in the paraumbilical area
    • Located approximately 4 cm from the umbilicus
    • May have direct course (larger perforators) or indirect course (smaller perforators)
  • Anastomoses: Forms connections with the superior epigastric artery within the rectus muscle above the umbilicus

• Superficial Inferior Epigastric Artery (SIEA)

  • Origin: Femoral artery just below the inguinal ligament
  • Course: Ascends anterior to the rectus sheath in the subcutaneous tissue
  • Distribution: Supplies the skin and subcutaneous tissue of the lower anterior abdominal wall
  • Anastomoses: Forms connections with perforators from the deep inferior epigastric system

• Deep Circumflex Iliac Artery

  • Origin: External iliac artery
  • Course: Runs parallel to the inguinal ligament along the iliac crest
  • Distribution: Supplies the lower lateral abdominal wall
  • Branches: Ascending branch anastomoses with the lower intercostal arteries

• Superficial Circumflex Iliac Artery

  • Origin: Femoral artery
  • Course: Runs laterally in the subcutaneous tissue parallel to the inguinal ligament
  • Distribution: Supplies the skin over the iliac crest and lower lateral abdominal wall

Anastomotic Connections

• Multiple "choke" vessels (narrow anastomotic connections) exist between:
  • Superior and deep inferior epigastric arteries within the rectus muscle
  • Deep inferior epigastric perforators and lateral cutaneous branches of intercostal arteries
  • Deep inferior epigastric system and deep circumflex iliac artery
  • Superficial inferior epigastric artery and superficial circumflex iliac artery

Venous Drainage

Superficial Venous System

• Superficial Inferior Epigastric Vein (SIEV)

  • Drainage: Collects blood from the skin and subcutaneous tissues of the lower abdomen
  • Course: Descends in the subcutaneous tissue
  • Termination: Shows considerable variation 4
    • May drain into the femoral vein
    • May drain into the great saphenous vein or saphenous bulb
    • May drain into the deep inferior epigastric vein
    • Multiple trunks present in 40% of cases
  • Clinical significance: Important for superficial inferior epigastric artery flap surgery

• Superficial Circumflex Iliac Vein

  • Drainage: Drains the lower lateral abdominal wall
  • Termination: May join the SIEV or drain directly into the femoral vein

• Thoracoepigastric Vein

  • Drainage: Runs vertically along the lateral thoracic and abdominal wall
  • Connections: Links the axillary vein above with the femoral vein below
  • Clinical significance: Important collateral pathway in inferior vena cava obstruction

Deep Venous System

• Deep Inferior Epigastric Veins

  • Typically paired veins accompanying the deep inferior epigastric artery (90% of cases) 3
  • Drainage: Collect blood from the rectus abdominis muscle and perforating branches
  • Termination: External iliac vein

• Superior Epigastric Veins

  • Accompany the superior epigastric artery
  • Drainage: Upper rectus abdominis muscle and overlying tissues
  • Termination: Internal thoracic veins

• Deep Circumflex Iliac Veins

  • Accompany the deep circumflex iliac artery
  • Termination: External iliac vein

Clinical Significance

• Understanding this vascular anatomy is crucial for:

  • Abdominal wall flap surgery, particularly DIEA perforator flaps and SIEA flaps
  • Abdominoplasty procedures where preservation of SEA perforators adjacent to the costal margin can improve abdominal wall perfusion 2
  • Surgical approaches to the abdominal wall to minimize vascular complications

• The unpredictable orientation and course of DIEA perforators may account for ischemia-related morbidity observed with DIEA-based perforator flaps 2

• Preoperative imaging with CT angiography is valuable for mapping the perforator anatomy before procedures like DIEP flap breast reconstruction 5