List of external rotators of the human body

List of External Rotators of the Human Body

The human body consists of several muscles that perform the function of external rotation. External rotation, also known as lateral rotation, is the outward (lateral) rotation of a joint or limb. This article provides a detailed list of the external rotators of the human body.

Muscles Involved in External Rotation

The primary muscles involved in external rotation of the human body are:

• Infraspinatus: This muscle is one of the four rotator cuff muscles and is involved in the external rotation of the shoulder.
• Teres minor: This muscle is also a part of the rotator cuff and aids in the external rotation of the shoulder.
• Posterior deltoid: This muscle is involved in the external rotation, extension, and horizontal abduction of the shoulder.
• Piriformis: This muscle is located in the buttock region and is involved in the external rotation of the hip.
• Obturator internus and Obturator externus: These muscles are involved in the external rotation of the hip.
• Gemellus superior and Gemellus inferior: These muscles assist in the external rotation of the hip.
• Quadratus femoris: This muscle is also involved in the external rotation of the hip.

File:Infraspinatus muscle - animation.gif

Animation of the Infraspinatus muscle, one of the external rotators of the shoulder

Function of External Rotators

The external rotators of the human body play a crucial role in maintaining stability and mobility. They allow the rotation of the limbs away from the center of the body, which is essential for various daily activities and sports movements. For instance, the external rotators of the shoulder allow the arm to rotate outward, enabling actions like throwing a ball or swimming.

Disorders Related to External Rotators

Disorders related to the external rotators can result in pain, stiffness, and limited mobility. Some common conditions include:

• Rotator cuff tear: This is a common injury that affects the rotator cuff in the shoulder, which includes the infraspinatus and teres minor muscles.
• Piriformis syndrome: This condition occurs when the piriformis muscle compresses the sciatic nerve, causing pain and numbness in the buttock and along the path of the sciatic nerve.

See Also

• List of muscles of the human body
• Rotator cuff
• Hip muscles