Question

The thyrocervical trunk is a branch of which part of the subclavian artery?

• A. 1st
• B. 2nd
• C. 3rd
• D. None

Hint:

Think VIT - the branches that arise medial to scalenus anterior.

Answer 1

The Correct Option is A

Step 1: The subclavian artery is divided into three parts by the scalenus anterior muscle. The first part lies medial to the muscle, the second part lies behind it, and the third part lies lateral to it.

Step 2: The first part gives the major branches: the vertebral artery, the internal thoracic (internal mammary) artery, and the thyrocervical trunk. On the left side the costocervical trunk also arises from the first part.

Step 3: The second part typically gives the costocervical trunk on the right side. The third part may give the dorsal scapular artery.

Step 4: Because the thyrocervical trunk arises from the first part of the subclavian artery, option a is correct.