Subscapularis Muscle – Attachments, Action & Innervation

Author: Scott A. Sheffield MS

Last update:

The subscapularis is a triangular muscle that fills the subscapular fossa. The Subscapularis muscle is one of the rotator cuff muscles, helping to stabilize the head of the humerus in the glenoid fossa during shoulder movements.

image descriptionSubscapularis Muscle

An image showing few muscles attached to the upper limb (Deltoid, Pectoralis major, Latissimus dorsi, Biceps brachii, Brachioradialis)
An image showing few muscles attached to the upper limb (Deltoid, Pectoralis major, Latissimus dorsi, Biceps brachii)
An image showing the Subscapularis Muscle (highlighted) attached to the upper limb along with other muscles (Teres major, Coracobrachialis, Brachialis)
An image showing Subscapularis Muscle attached to the upper limb
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image descriptionAttachments of Subscapularis Muscle: Origin & Insertion

Origin: (proximal attachments)
Subscapular fossa of the scapula.

Insertion: (distal attachments)
Lesser tubercle of humerus.

Check out this expert guide on learning the anatomy of the arm and shoulder muscles (step-by-step walkthrough).

An image showing few muscles attached to the upper limb (Deltoid, Pectoralis major, Latissimus dorsi, Biceps brachii, Brachioradialis)
An image showing Subscapularis Muscle attached to the upper limb
An image showing the Origin and Insertion of the Subscapularis Muscle on the upper limb
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Actions of Pectoralis Major Muscle:

image descriptionMedially rotates the arm  at the shoulder (glenohumeral) joint.

Innervation of Biceps Brachii:

image descriptionNerves to the muscle:
Upper and lower subscapular nerves.
image descriptionNerve roots:
C5, C6, and C7.
An image showing the upper and lower subscapular nerves coming out of the brachial plexus
An image showing the upper and lower subscapular nerves coming out of the brachial plexus
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Interactive quiz with the muscles that act on the arm

Muscles That Act On The Anterior Arm

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