The subscapularis muscle is located in the anterior aspect of the scapula, forming part of the rotator cuff in the shoulder. It is a triangular muscle that lies beneath the scapula, covering the subscapular fossa.

Origin:
Originating from the subscapular fossa of the scapula, the subscapularis takes its starting point from the bony surface on the anterior aspect of the shoulder blade.

Insertion:
The muscle inserts into the lesser tubercle of the humerus, forming a connection with the upper part of the arm bone.

Function:
Functionally, the subscapularis is a powerful medial rotator of the shoulder joint. It plays a key role in turning the humerus inward, contributing to the overall range of motion in the shoulder. Additionally, the muscle assists in stabilizing the shoulder joint during arm movements, providing dynamic stability and preventing dislocation. The subscapularis is actively engaged in actions such as throwing, reaching, and lifting, showcasing its significance in shoulder biomechanics and overall upper limb function.