The Axilla & Pectoral Region Muscle (BS, Act, Inn)

Question 1

Pectoralis minor (Act, BS, Inn)

Answer 1

Act: stabilizes scapula by pulling it anteriorly & inferiorly against posterior thoracic wall

BS: pectoral branch(es) of thoracoacromial arterial trunk

Inn: medial pectoral nerve pierces the muscle

Question 2

Subclavius (Act, BS, Inn)

Answer 2

Act: anchors and depresses clavicle

BS: clavicular branch(es) of thoracoacromial trunk

Inn: nerve to subclavius

Question 3

Serratus Anterior (Act, BS, Inn)

Answer 3

Act: protracts scapula, rotates scapula, holds scapula against thorax

BS: lateral thoracic artery

Inn: long thoracic nerve

Question 4

Pectoralis Major (A, BS, Inn)

Answer 4

A:

1. adducts & medial rotates humerus
2. draws scapula anteriorly & inferiorly (via clavicle)
3. clavicular portion flexes humerus
4. sternal portion can extend humerus while it is in this flexed position

BS: pectoral branch(es) of thoracoacromial arterial trunk

Inn: lateral & medial pectoral nerves