pectoralis minor muscle

The pectoralis minor muscle is a muscle of the pectoral region lying deep to and completely covered by the pectoralis major muscle.

It is an important anatomical landmark in two senses:

  • it arbitrarily divides the axillary artery into 3 parts
  • it arbitrarily divides the axillary lymph nodes into 3 levels
  • Summary

    • origin: anterior 3-5 ribs near the costal cartilages
    • insertion: medial and upper aspect of the coracoid process of the scapula
    • innervation: medial and lateral pectoral nerves
    • action
      • depresses shoulder
      • when scapula fixed, elevation of 3-5 ribs

    Variant anatomy

    • pre-fixed origin: ribs 2-4
    • post-fixed origin: ribs 4-6
    • absence
    Siehe auch:
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