External iliac nodes lie along the external iliac vessels, draining the lower limb and pelvic wall.
The external iliac lymph nodes are a chain of lymph nodes located along the external iliac vessels. They serve as major conduits for lymph drainage from the lower abdominal wall, pelvic organs, and lower limbs. These nodes are essential for the immune surveillance of pelvic and lower limb regions and are commonly involved in the spread of malignancies such as cervical, bladder, and prostate cancers.
The external iliac lymph nodes are oval or bean-shaped structures organized into three main groups based on their anatomical position relative to the external iliac artery:
Each node consists of a capsule, subcapsular sinus, cortex with lymphoid follicles (B cells), and a medulla with cords and sinuses. Afferent lymphatic vessels enter the node, and filtered lymph exits via efferent vessels to common iliac nodes.
External iliac nodes lie along the length of the external iliac artery and vein, from the level of the inguinal ligament up to the bifurcation of the common iliac artery. They are embedded in the connective tissue of the pelvic sidewall, anterior to the psoas major muscle.
Group | Anatomical Position |
---|---|
Lateral | Lateral to external iliac artery |
Medial | Medial or anterior to artery, near vein |
Intercalated | Between artery and vein |