ANATOMY – AXILLA
Introduction:
- Axilla, also known as the armpit, is the space between the upper part of the
arm and the lateral thoracic wall.
Boundaries:
- Apex: Triangular space, also known as the service auxiliary canal, directed
medially and upwards.
- Anterior: Clavicle
- Posterior: Superior border of the scapula
- Medial: Outer border of the first rib
Base:
- Lower end of the axilla, directed downwards, formed by the skin and auxiliary
fascia.
- Bounded anteriorly by the anterior axillary fold and posteriorly by the
posterior axillary fold.
Walls of the Axilla:
- Anterior Wall: Composed of the pectoralis major muscle.
- Posterior Wall: Composed of subscapularis, latissimus dorsi, and teres major.
- Medial Wall: Includes upper 4 to 5 ribs, intercostal muscles, and upper part of
serratus anterior.
- Lateral Wall: Formed by the intertubercular sulcus of the humerus and
tendons of various muscles.
Contents of the Axilla:
- Axillary artery and its branches, axillary vein and its tributaries, chords of the
brachial plexus, long thoracic nerve, intercostal brachial nerves, axillary lymph
nodes, and associated structures.
Introduction:
- Axilla, also known as the armpit, is the space between the upper part of the
arm and the lateral thoracic wall.
Boundaries:
- Apex: Triangular space, also known as the service auxiliary canal, directed
medially and upwards.
- Anterior: Clavicle
- Posterior: Superior border of the scapula
- Medial: Outer border of the first rib
Base:
- Lower end of the axilla, directed downwards, formed by the skin and auxiliary
fascia.
- Bounded anteriorly by the anterior axillary fold and posteriorly by the
posterior axillary fold.
Walls of the Axilla:
- Anterior Wall: Composed of the pectoralis major muscle.
- Posterior Wall: Composed of subscapularis, latissimus dorsi, and teres major.
- Medial Wall: Includes upper 4 to 5 ribs, intercostal muscles, and upper part of
serratus anterior.
- Lateral Wall: Formed by the intertubercular sulcus of the humerus and
tendons of various muscles.
Contents of the Axilla:
- Axillary artery and its branches, axillary vein and its tributaries, chords of the
brachial plexus, long thoracic nerve, intercostal brachial nerves, axillary lymph
nodes, and associated structures.
