Beverly Hosford July 14, 2025 Anatomy, Fitness Pectoralis Minor Muscle: Attachments, Actions, Exercises and More Beverly Hosford July 14, 2025 Anatomy, Fitness The pectoralis minor is a shoulder muscle that connects the scapula to the ribs, effecting scapular motion and breathing when the scapula is fixed. It is active anytime we need stabilization of the shoulder girdle with the arms in front of us.