Humans have approximately 500–600 lymph nodes distributed throughout the body, with clusters found in the underarms, groin, neck, chest, and abdomen.
- The thoracic duct
- The lymphatics of the head, face, and neck
- The lymphatics of the upper extremity
- The lymphatics of the lower extremity
- The lymphatics of the abdomen and pelvis
- The lymphatic vessels of the thorax
Lymph nodes of the head and neck
Lymph nodes of the thorax
- Lymph nodes of the lungs: The lymph is drained from the lung tissue through subsegmental, segmental, lobar and interlobar lymph nodes to the hilar lymph nodes, which are located around the hilum (the pedicle, which attaches the lung to the mediastinal structures, containing the pulmonary artery, the pulmonary veins, the main bronchus for each side, some vegetative nerves and the lymphatics) of each lung. The lymph flows subsequently to the mediastinal lymph nodes.
- Mediastinal lymph nodes: They consist of several lymph node groups, especially along the trachea (5 groups), along the esophagus and between the lung and the diaphragm. In the mediastinal lymph nodes arises lymphatic ducts, which drains the lymph to the left subclavian vein (to the venous angle in the confluence of the subclavian and deep jugular veins).
The mediastinal lymph nodes along the esophagus are in tight connection with the abdominal lymph nodes along the esophagus and the stomach. That fact facilitates spreading of tumor cells through these lymphatics in cases of cancers of the stomach and particularly of the esophagus.
Through the mediastinum, the main lymphatic drainage from the abdominal organs goes via the thoracic duct (ductus thoracicus), which drains majority of the lymph from the abdomen to the above mentioned left venous angle.
Lymph nodes of the arm
These drain the whole of the arm, and are divided into two groups, superficial and deep. The superficial nodes are supplied by lymphatics that are present throughout the arm, but are particularly rich on the palm and flexor aspects of the digits.
- Superficial lymph nodes of the arm:
- Deep lymph nodes of the arm: These comprise the axillary nodes, which are 20-30 individual nodes and can be subdivided into:
- Lateral nodes
- Anterior or pectoral nodes
- Posterior or subscapular nodes
- Central or intermediate nodes
- Medial or subclavicular nodes
Lymphatic vessels in the human body