|Deep muscles of the chest and front of the arm, with the boundaries of the axilla. (Subscapularis visible near center top.)|
|Gray's||subject #123 440|
|Insertion:||lesser tubercle of humerus|
|Artery:||transverse cervical artery,  subscapular artery|
|Nerve:||upper subscapular nerve, lower subscapular nerve (C5, C6)|
|Action:||rotates medially humerus; stabilizes shoulder|
The Subscapularis is a large triangular muscle which fills the subscapular fossa.
Origin and insertion
Some fibers arise from tendinous laminæ which intersect the muscle and are attached to ridges on the bone; others from an aponeurosis, which separates the muscle from the Teres major and the long head of the Triceps brachii.
The Subscapularis rotates the head of the humerus medially (internal rotation); when the arm is raised, it draws the humerus forward and downward. It is a powerful defense to the front of the shoulder-joint, preventing displacement of the head of the humerus.
- "Tufts". Retrieved 2007-12-11.
This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.