Coracobrachialis muscle

The Coracobrachialis is the smallest of the three muscles that attach to the coracoid process of the scapula. (The other two muscles are pectoralis minor and biceps brachii.) It is situated at the upper and medial part of the arm.

It is perforated by and innervated by the musculocutaneous nerve.

Origin and insertion
It arises from the apex of the coracoid process, in common with the short head of the Biceps brachii, and from the intermuscular septum between the two muscles.

It is inserted by means of a flat tendon into an impression at the middle of the medial surface and border of the body of the humerus between the origins of the Triceps brachii and Brachialis.

Action
The coracobrachialis draws the humerus forward (shoulder flexion) and towards the torso (shoulder adduction).

Innervation
The coracobrachialis muscle is innervated by the musculocutaneous nerve which arises from the anterior division of the upper (C5, C6) & middle trunks (C7) of the brachial plexus.