Pectoralis Minor Muscle, Lateral View

Description

Arising from the anterior surfaces of ribs 3 to 5 near their costochondral junctions, the pectoralis minor courses superolaterally to insert on the medial border and superior surface of the coracoid process of the scapula. From a lateral thoracic perspective, its fibers sit deep to where pectoralis major would lie and anterior to the serratus anterior slips on the lateral rib cage, placing it between the anterior chest wall and the scapular coracoid. Posteriorly, the thoracic vertebrae and ribs frame the muscle’s rib origins, while the clavicle and acromion define the superior shoulder girdle landmarks. Clear rib-to-scapula anatomy. This view matters because pectoralis minor is a common driver of scapular anterior tilt and protraction, patterns that narrow the costoclavicular and retropectoralis minor spaces and can contribute to neurovascular symptoms in thoracic outlet syndrome. Clinicians also track its relationship to the axillary vessels and brachial plexus cords as they pass deep to pectoralis minor, a key concept when interpreting provocative maneuvers, ultrasound, or planning targeted injections and releases. The muscle’s accessory respiratory role, elevating ribs when the scapula is fixed, is easier to teach when the rib origins are unobscured. Use this asset in gross anatomy and kinesiology teaching to anchor discussions of scapulothoracic mechanics, serratus anterior force couples, and accessory muscles of inspiration in the male thorax. It also fits well in surgical, anesthesia, and sports medicine materials covering infraclavicular blocks, pectoralis minor tenotomy, and differential diagnosis of anterior shoulder pain. Anatomical accuracy verified by SciePro's Medical Advisory Board.