Editing Trachea (section)

=== Nearby structures ===
The trachea passes by many structures of the [[neck]] and chest ([[thorax]]) along its course.

In front of the upper trachea lies connective tissue and skin.<ref name="GA2016" /> Several other structures pass over or sit on the trachea; the [[Jugular venous arch|jugular arch]], which joins the two [[anterior jugular vein]]s, sits in front of the upper part of the trachea. The [[Sternohyoid muscle|sternohyoid]] and [[sternothyroid muscle]]s stretch along its length. The thyroid gland also stretches across the upper trachea, with the isthmus overlying the second to fourth rings, and the lobes stretching to the level of the fifth or sixth cartilage.<ref name="GA2016" /> The blood vessels of the thyroid rest on the trachea next to the isthmus; [[superior thyroid arteries]] join just above it, and the [[inferior thyroid veins]] below it.<ref name="GA2016" /> In front of the lower trachea lies the manubrium of the [[sternum]], the [[Thymus#Involution|remnants]] of the [[thymus]] in adults. To the front left lie the large blood vessels the [[aortic arch]] and its branches the left [[common carotid artery]] and the [[Brachiocephalic artery|brachiocephalic trunk]]; and the left [[brachiocephalic vein]]. The deep [[cardiac plexus]] and lymph nodes are also positioned in front of the lower trachea.<ref name="GA2016" />

Behind the trachea, along its length, sits the [[Esophagus|oesophagus]], followed by connective tissue and the [[vertebral column]].<ref name=GA2016 /> To its sides run the [[carotid arteries]] and inferior thyroid arteries; and to its sides on its back surface run the [[recurrent laryngeal nerve]]s in the upper trachea, and the [[vagus nerve]]s in the lower trachea.<ref name=GA2016 />

The trachealis muscle contracts during [[cough]]ing, reducing the size of the [[lumen (anatomy)|lumen]] of the trachea.<ref name="Furlow2018" />

<gallery>
File:CT-Thorax-5.0-B70f.ogg|CT scan of the thorax (axial lung window)
File:COR-2-STND-CHEST.ogg|CT scan of the thorax (coronal lung window) 
File:COR-2-STND-CHEST-MEDIASTINUM.ogg|CT scan of the thorax (coronal mediastinal window) 
File:Cross section of a trachea and esophagus.svg|Cross section of a trachea and esophagus
File:Sternohyoid muscle.PNG|The [[sternohyoid muscle|sternohyoid]] and [[sternothyroid muscle]]s lie on top of the upper part of the trachea
File:Blausen 0534 Goiter.png|The thyroid gland also lies on top of the trachea, and lies below the cricoid cartilage. 
</gallery>