Anatomy 101: Shoulder Muscles

What gives you the ability to throw a ball or reach for the top shelf? Shoulder muscles. Brush up on your anatomy knowledge with the interactive anatomy tool on www.handcare.org and learn about the muscles of the shoulder.

The muscles of the shoulder include:

Deltoid: The Deltoid muscle is located on the outside of the shoulder. It has three major parts that control shoulder flexion (forward elevation of the arm), shoulder abduction (outside arm elevation away from the midline of the body) and shoulder extension (movement of the arm behind the back).

Infraspinatus: The Infraspinatus is a rotator cuff muscle that controls shoulder external rotation (rotation of the arm such that the hand moves away from the midline).

Subscapularis: The Subscapularis is a rotator cuff muscle that controls shoulder internal rotation (rotation of the arm such that the hand moves towards the midline).

Supraspinatus: The Supraspinatus is a rotator cuff muscle that primarily controls shoulder abduction (outside arm elevation away from the midline of the body).

Teres Major: The Teres Major is a shoulder muscle that controls shoulder adduction (drawing the raised arm down towards the body).

Teres Minor: The Teres Minor is a rotator cuff muscle that controls shoulder external rotation (rotation of the arm such that the hand moves away from the midline).

Latissimus: The Latissimus is one of the largest muscles in the back and primarily controls shoulder adduction (drawing the raised arm down towards the body).