Root of the lung

Root of the lung
Mediastinal surface of right lung.
Mediastinal surface of left lung.
Details
Identifiers
Latin	radix pulmonis
TA98	A06.5.01.016
TA2	3278
FMA	268155
Anatomical terminology

A little above the middle of the mediastinal surface of each lung, and nearer its posterior than its anterior border, is its root, by which the lung is connected to the heart and the trachea.

The root is formed by the bronchus, the pulmonary artery, the pulmonary veins, the bronchial arteries and veins, the pulmonary plexuses of nerves, lymphatic vessels, bronchial lymph glands, and areolar tissue, all of which are enclosed by a reflection of the pleura.

The root of the right lung lies behind the superior vena cava and part of the right atrium, and below the azygos vein. That of the left lung passes beneath the aortic arch and in front of the descending aorta; the phreni pericardiacophrenic artery and vein, and the anterior pulmonary plexus, lie in front of each, and the vagus and posterior pulmonary plexus behind each; below each is the pulmonary ligament.

The chief structures composing the root of each lung are arranged in a similar manner from before backward on both sides, viz., the upper of the two pulmonary veins in front; the pulmonary artery in the middle; and the bronchus, together with the bronchial vessels, behind.

From above downward, on the two sides, their arrangement differs, thus:

On the right side their position is—eparterial bronchus, pulmonary artery, hyparterial bronchus, pulmonary veins, but on the left side their position is—pulmonary artery, bronchus, pulmonary veins.

The lower of the two pulmonary veins, is situated below the bronchus, at the apex or lowest part of the hilus.

Additional images

• 
  The phrenic nerve and its relations with the vagus nerve.

External links

• Template:EMedicineDictionary
• Atlas image: lung_lymph at the University of Michigan Health System - "Transverse section through lung"
• thoraxlesson2 at The Anatomy Lesson by Wesley Norman (Georgetown University)
• Diagram at seer.cancer.gov (#21)

This article incorporates text in the public domain from page 1097 of the 20th edition of Gray's Anatomy (1918)