Actions & innervation of Coracobrachialis.
Knowledge of origins & insertions is NOT required but an appreciation of the surface topography is required.
Curriculum
Origin | Coracoid process of scapula |
Insertion | Antero-medially on Shaft of Humerus |
Nerve supply | Musculocutaneous nerve |
Actions | Flexion of the arm and weak adductor |
Though the curriculum says origin and insertion not required, we’ve included them as that knowledge will help you understand the movements better based on muscle orientation.
![Coracobrachialis muscle Origin and Insertions](https://cdn.frcemprep.com/wp-content/uploads/2021/04/Coracobrachialis.jpg)
Coracobrachialis muscle Origin and Insertions – Image modified from BodyParts3D, © The Database Center for Life Science licensed under CC Attribution-Share Alike 2.1 Japan
The muscle is named as per it’s origin and insertion. From coracoid to the arm (Brachium = Arm) hence Coraco-brachialis.
The position of muscle should help you understand the actions when it contracts. It’ll pull the arm anteriorly (flexion) and medially (adduction)
All the anterior arm muscles – Coracobrachialis, Brachialis and Biceps brachii are supplied by the same nerve – The Musculocutaneous nerve, the terminal branch of the lateral cord of the brachial plexus (C5-C7). The nerve becomes lateral cutaneous nerve of forearm to supply lateral part of forearm. Muscles of Upper Arm and Skin of Forearm are supplied.
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