Inguinal Lymph Nodes

The inguinal lymph nodes are superficial and deep lymphatic nodes located in the inguinal (groin) region. They are responsible for filtering lymph from the lower limb, external genitalia, perineum, and lower abdominal wall. These nodes are important in clinical examination due to their accessibility and are frequently involved in infections, malignancies, and immune responses.

Structure

The inguinal lymph nodes are divided into two main groups:

1. Superficial Inguinal Nodes

• Located in the superficial fascia, inferior to the inguinal ligament
• Arranged in a T-shaped distribution:
  • Horizontal group: Parallel to inguinal ligament
  • Vertical group: Along the terminal part of the great saphenous vein

2. Deep Inguinal Nodes

• Located deep to the fascia lata, medial to the femoral vein
• Include 1–3 nodes, one of which is Cloquet’s (Rosenmüller’s) node — found in the femoral canal

Location

Inguinal nodes lie in the upper thigh and groin region, inferior to the inguinal ligament and adjacent to the femoral triangle.

Function

• Superficial group drains:
  • External genitalia (except glans penis/clitoris)
  • Perineum
  • Lower anal canal (below pectinate line)
  • Lower abdominal wall (below umbilicus)
  • Buttock skin and lower limb (via superficial vessels)
• Deep group drains:
  • Glans penis or clitoris
  • Deep perineal structures
  • Deep lymphatics of lower limb
• Efferent drainage: Both groups ultimately drain into external iliac lymph nodes

Clinical Significance

• Palpable enlargement: Common in infections of lower limb, STIs, or skin lesions
• Sentinel node role: In cancers such as penile, vulvar, or anal cancers
• Cloquet’s node: Examined during oncologic staging as a bridge node between inguinal and iliac regions