The musculocutaneous nerve travels through the __________ trunk and the ________ cord.

The musculocutaneous nerve is primarily derived from the upper trunk of the brachial plexus, which is formed by the merging of the ventral rami of C5, C6, and C7 spinal nerves. This is significant because the upper trunk serves as a key structure that gives rise to several important nerves that innervate the muscles and skin of the shoulder and upper limb.

Additionally, the musculocutaneous nerve is associated with the lateral cord of the brachial plexus, which consists of contributions from the anterior divisions of the upper and middle trunks. The lateral cord plays a vital role in the innervation of specific muscles in the arm, particularly those involved in elbow flexion, where the musculocutaneous nerve predominantly functions.

Understanding the anatomical pathways through which the musculocutaneous nerve travels helps elucidate its clinical significance, especially in cases of nerve injuries or compressions that may lead to motor or sensory deficits in the corresponding areas innervated by this nerve.