Quick Facts
Origin: Subscapular fossa of scapula.
Insertion: Lesser tubercle of humerus.
Action: Medially rotates and stabilizes arm at glenohumeral (shoulder) joint.
Innervation: Upper and lower subscapular nerves (C5-C7).
Arterial Supply: Subscapular, suprascapular, and lateral thoracic arteries.
Related parts of the anatomy
Origin
The subscapularis muscle originates from the:
- subscapular fossa of scapula;
- aponeurosis that surrounds the muscle.
Insertion
The fibers of the subscapularis muscle travel superolaterally and insert, via a broad tendon, onto the lesser tubercle of the humerus. Part of this tendon also merges with the capsule of the glenohumeral (shoulder) joint.
Key Features & Anatomical Relations
The subscapularis muscle is one of the rotator cuff muscles. It is a thick, multipennate type of skeletal muscle. It is located:
- anterior (deep) to the scapula, the glenohumeral (shoulder) joint, and the subtendinous bursa of subscapularis muscle;
- posterior to the serratus anterior and teres minor muscles, and the axillary artery and vein;
- superior to the teres major and latissimus dorsi muscles;
- lateral to the rhomboid major and minor muscles.
The subscapularis muscle contributes to the formation of the posterior wall of the axilla.
Actions
The subscapularis muscle medially rotates the arm at the glenohumeral (shoulder) joint. It is one of the four rotator cuff (SITS) muscles, the other three being the supraspinatus, infraspinatus, and teres minor muscles. These muscles work together to stabilize the glenohumeral joint, by holding the head of the humerus in the glenoid fossa of the scapula, during its movements (Standring, 2016).
List of Clinical Correlates
- Injury or rupture of rotator cuff
References
Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41st edn.: Elsevier Limited.
Actions
The subscapularis muscle medially rotates the arm at the glenohumeral (shoulder) joint. It is one of the four rotator cuff (SITS) muscles, the other three being the supraspinatus, infraspinatus, and teres minor muscles. These muscles work together to stabilize the glenohumeral joint, by holding the head of the humerus in the glenoid fossa of the scapula, during its movements (Standring, 2016).
Learn more about this topic from other Elsevier products
Subscapularis Muscle
The subscapularis muscle is the primary muscle of the rotator cuff that dynamically resists posterior translation of the humeral head (Provencher et al, 2011).