- This article refers to the anatomy of the deltoid muscles in the cat. For the human muscle see Deltoid muscle.
The deltoid muscles are just lateral to the Trapezius muscles. Anatomically, there are only two deltoids in the cat, and that is the Acromiodeltoid, and the Spinodeltoid. However, the Clavobranchialis, is now also considered as a deltoid, so as to conform to Human Anatomy standards. It is therefore called Clavodeltoid.
It is the shortest Deltoid muscle. It lies lateral to the clavodeltoid, and in a more husky cat, this can only be seen by lifting the clavodeltoid. Origin, Acromion process, Insertion, deltoid ridge, Action, Raises and Rotates the humerus outward
A stout and short muscle lying posterior to the acromiodeltoid. It lies along the lower border of the scapula, and it passes through the upper arm, across the upper end of muscles of the upper arm. Origin, spine of the scapula, Insertion, deltoid ridge, Action, raises and rotates the humerus outward.
Clavodeltoid (Clavobrachialis; Cleidobrachialis)
The clavodeltoids are the brachial (arm) continuation of the clavotrapezius. It is the muscle on the anterior surface of the shoulder and anterior to the pectoantebrachialis
. The clavotrapezius and the clavodeltoid (clavobrachialis) are sometimes considered by anatomists as consisting one muscle, which is the cephalobranchial (literally, head to arm). The clavicle is embedded under this muscle. Origin, Clavicle and Fibers of the Clavotrapezius, Insertion, Ulna, Action, flexor of the forearm.