The inferior thyroid artery is a paired blood vessel located in each side of anterior part of the human neck. It is one of the four branches into which the thyrocervical trunk divides, supplying the inferior portion of the thyroid gland with oxygenated blood. It has an irregular ascending course, giving off several smaller, collateral arterial offshoots.
The inferior thyroid artery arises from the thyrocervicval trunk as its terminal branch. From its point of origin, it runs upwards and medially across the anterior surface of the anterior scalene muscle, behind the internal jugular vein and the common carotid artery. As it runs, it forms an arch at the level of the sixth cervical vertebra and approaches the posterior surface of the lower portion of the thyroid gland lateral lobe. At this point, the inferior thyroid artery sends glandular branches to the gland parenchyma (the essential, functional tissue of an organ).
As it continues its course, the inferior thyroid also gives off tracheal branches to the trachea and esophageal offshoots to supply the esophagus and pharynx. At the end of its course, it gives off the inferior laryngeal artery, which enters the wall of the larynx and anastomoses with the superior laryngeal, which originates from the superior thyroid artery.
