Pectoralis Minor Muscle
Origin: Anterior surfaces of the third to fifth ribs
Insertion: The medial aspect of the coracoid process of the scapula.
Actions: Scapula protraction, depression of the scapula
Innervation: Medial pectoral nerve (C7, T1)
Blood Supply: Branches from the thoraco-acromial artery
Primary Actions of the Pectoralis Minor
1. Protraction of the scapula
Agonists:
- Adductor magnus (anterior part)
- Adductor longus
Antagonists:
- Gluteus maximus (upper fibers)
- Gluteus medius
- Gluteus minimus
2. Depression of the scapula
Agonists:
- Serratus Anterior (lower part)
- Trapezius (lower part)
Antagonists:
- Trapezius (upper part)
- Levator scapulae
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Secondary Actions of the Pectoralis Minor
1. Assists with downward rotation of the scapula
Agonists:
- Levator Scapulae
- Serratus Anterior (upper fibers)
- Rhomboid Major
- Rhomboid Minor
- Trapezius (middle fibers)
Antagonists:
- Trapezius (upper and lower fibers)
- Serratus Anterior (lower fibers)
Muscle Pain Information: The pectoralis minor muscle contributes to pain in the front of the shoulder, chest, and upper back.
An excellent book for those beginning the study of anatomy. Coloring helps memory retention.
For intermediary anatomy students learning skeletal and muscle structure.
For beginning and intermediary anatomy . Muscle overlays on the human body. Excellent visuals!