Pectoralis minor

Pectoralis minor is a thin, triangular muscle, situated at the upper part of the chest, beneath the Pectoralis major in the human body. It contributes to the thoracobrachial motion and plays a significant role in the movement of the Scapula.

Anatomy

The pectoralis minor is located underneath the pectoralis major. It attaches at the third, fourth, and fifth ribs near their cartilage and extends to the medial part of the superior surface of the Coracoid process of the scapula.

Function

The pectoralis minor muscle has several functions. It draws the scapula forward and downward against the thoracic wall, which allows the arm to move across the chest. It also raises the ribs when the scapula is stationary, aiding in respiratory function.

Clinical significance

The pectoralis minor can be involved in several clinical conditions. It can contribute to Thoracic outlet syndrome, a group of disorders that occur when certain blood vessels or nerves are compressed. It can also be involved in Shoulder impingement syndrome, a condition where the tendons of the rotator cuff muscles become irritated and inflamed.

See also

• Pectoralis major
• Scapula
• Coracoid process
• Thoracic outlet syndrome
• Shoulder impingement syndrome

References

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  Pectoralis minor muscle diagram
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  Pectoralis minor muscle and shoulder blade
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  Anatomical illustration from Braus 1921
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  Pectoralis minor muscle animation
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  Pectoralis minor