Inguinal lymph nodes

Function

The inguinal nodes drain the entire lower limb, the perineum and the lower abdominal wall — the body's lower customs house. They swell after every stubbed toe and foot infection, and characteristically in sexually transmitted infections of the genital region.

Their drainage line — the saphenofemoral junction — is where the great saphenous vein meets the femoral, and where the surgeon's knife must respect the node-bearing fat during varicose vein surgery.

Blood supply

Superficial circumflex iliac and superficial external pudendal arteries.

Nerve supply

Sympathetic fibres with the vessels.

Clinical relevance

Groin nodes and limb infection

Cellulitis of the leg presents with tender groin nodes — the lymphatic echo of the primary battle.

Genital cancers

Penile, vulvar and anal cancers drain here first — sentinel mapping increasingly spares unnecessary clearance.