Which section of the body do the brachial plexus nerves innervate?

The brachial plexus is a network of nerves that arises from the spinal nerves C5 to T1 and is responsible for providing motor and sensory innervation to the entire upper quarter of the body. This includes the shoulder, arm, forearm, and part of the hand. The branching nature of the brachial plexus allows for innervation of multiple muscles and skin areas in these regions, facilitating movement and sensation.

Understanding the structure and function of the brachial plexus is crucial for recognizing its role in upper extremity function and the potential impact of injuries or conditions affecting it. For example, a lesion or compression in the brachial plexus can lead to weakness or loss of sensation in the arm and hand.

Other options refer to different anatomical regions that are not served by the brachial plexus. The lower quarter typically refers to areas innervated by the lumbosacral plexus, while the upper lower quarter encompasses regions below the upper extremities and is also irrelevant in this context. Head and neck areas are mainly innervated by cranial nerves, not by the brachial plexus. Therefore, the response indicating that the entire upper quarter is innervated by the brachial plex