The neurovascular structures of the pelvis include nerves, arteries, veins, and lymph nodes. These structures lie on the posterolateral walls of the pelvic cavity.
Generally the somatic nerves are the most lateral, arteries lie medial to nerves, and veins lie between these two.
Lymph nodes are usually clustered around the veins, and lymph vessels that come off these nodes ascend parallel to the veins. Now, let's take a closer look at the lymphatics and nerves of the pelvis specifically.
Let’s talk about the lymphatic drainage of the pelvis, which follows various major and minor groups of lymph nodes.
These lymph nodes have variable, sizes, numbers, and locations, and the lymph node clusters’ names are based on the adjacent structures and nearby blood supply.
Furthermore, these nodes are all interconnected, so their drainage often overlaps and can vary quite a bit.
First, there are the inguinal lymph nodes which lie around the inguinal ligament, and they’re divided into superficial and deep inguinal lymph nodes.
The superficial inguinal lymph nodes receive lymphatic drainage from the superficial lower limb, abdominal wall inferior to the umbilicus, gluteal region and superficial perineal structures such as the distal vagina, vulva and scrotum, and typically drain into the external iliac lymph nodes.
The deep inguinal lymph nodes receive lymph from the superficial inguinal nodes, as well as the deep portions of the lower limb, the glans clitoris in females or glans penis in males and the distal spongy urethra. These nodes typically drain into the external and common iliac lymph nodes.