Anatomically, which muscle acts as a landmark separating the axillary artery into its three parts, and what are the two cords that give rise to the median nerve?
- A Coracobrachialis; lateral and medial cords
- B Pectoralis minor; lateral and medial cords ✓
- C Subscapularis; posterior and medial cords
- D Pectoralis major; lateral and posterior cords
Correct answer: B. Pectoralis minor; lateral and medial cords
Explanation
The pectoralis minor muscle, which inserts into the coracoid process, crosses the second part of the axillary artery and divides it into three parts: proximal to, behind, and distal to the muscle. This is a key surgical landmark. The median nerve is formed by contributions from both the lateral cord (C5, C6, C7) and medial cord (C8, T1), which combine in a V-shaped union anterior to the axillary artery to form the median nerve, classically visible in surgical diagrams as a letter 'M' shaped arrangement.
Reference: BD Chaurasia's Human Anatomy, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.