The axilla is defined as a pyramidal anatomical space bounded by specific osteofascial walls: the medial wall formed by the intercostal muscles and serratus anterior on ribs 1–8, the lateral wall by the surgical neck of the humerus, the posterior wall by the subscapularis, infraspinatus, teres minor, and long head of the triceps, and the anterior wall by the pectoralis major and minor. Within this domain of human cross-sectional anatomy, vascular relationships are governed by a fixed medial-lateral positional rule where the axillary vein resides medial to the axillary artery throughout its course in the axial plane. Theoretically, posterior compartmentalization is characterized as significantly bulkier than the anterior compartment due to the concentration of rotator cuff muscles and deep fascia structures at this specific transverse level below the glenohumeral joint head.
The axilla is defined as a pyramidal anatomical space bounded by specific osteofascial walls: the medial wall formed by the intercostal muscles and serratus anterior on ribs 1–8, the lateral wall by …