The coracobrachialis is a small muscle located in the upper arm. It originates from the coracoid process of the scapula and inserts into the middle of the humerus. This muscle plays a role in flexing and adducting the arm at the shoulder joint. In addition to its primary functions, the coracobrachialis helps stabilize the shoulder during arm movements. It is innervated by the musculocutaneous nerve, which is responsible for transmitting signals from the nervous system to the muscle, allowing for coordinated movement.