Part of the complex lymphatic system that helps provide immunity to the human body, the inguinal lymph nodes are located in the groin area. These nodes can be either superficial or deep, and they lie in chains, carrying lymphatic fluid from the abdomen and groin area through the lymphatic system. The former are located along the crease of the groin near the inguinal ligament, a prominent ligament that helps protect and stabilize various abdominal organs. Deep lymph nodes, the largest of which is named Cloquet's node, can be found farther down the thigh, near the femoral artery.
Much like the cardiovascular system moves blood throughout the body to deliver oxygen to all of the individual body cells, the lymphatic system circulates lymph fluid throughout the body in order to help fight infection and disease and maintain overall immunity. With no central pump such as the heart, though, the lymphatic system relies on natural movement and muscular contractions to circulate this vital fluid. Areas drained by the inguinal lymph nodes include the genitalia, the buttocks, the lower wall of the abdomen, the feet, the legs and the anus, with fluid from these areas draining through the superficial nodes into the deep ones.
Inguinal lymph nodes, whether they are superficial or deep, are an important part of the lymphatic system. They were among the first lymph nodes to be discovered and were identified by Rufus of Ephesus during his anatomical studies of the first and second centuries A.D. Early study of the lymphatic system described the network itself fairly accurately but produced inaccurate theories regarding its function.
Enlarged lymph nodes in the groin area can be indicative of infection, injury, or even cancerous growths in these areas. Groin injury, such as an inguinal hernia, which is more common in men than women, can lead to enlargement of the nodes as the body works to heal. In general, any groin pain or presence of enlarged lymph nodes in the area should be brought to the attention of a medical professional to determine the underlying cause.
Enlarged lymph nodes in the inguinal region can in some cases indicate the presence of cancer in the anus or vulva. They also can be related to metastasis of existing cancers. This is because the lymphatic system, though its function is to prevent infection and fight cancers, also carries cancerous cells to other parts of the body once it has entered the system.