The axillary spaces are
anatomic spaces.
through which axillary contents leave the axilla. They consist of the
quadrangular space
The quadrangular space, also known as the quadrilateral space f Velpeau'' and the foramen humerotricipitale, is one of the three spaces in the axillary space. The other two spaces are: triangular space and triangular interval.
Structure
The q ...
,
triangular space
The triangular space (also known as the medial triangular space, upper triangular space, medial axillary space or foramen omotricipitale) is one of the three spaces found at the axillary space. The other two spaces are the quadrangular space and ...
, and
triangular interval
The triangular interval (also known as the lateral triangular space, lower triangular space, and triceps hiatus) is a space found in the axilla. It is one of the three intermuscular spaces found in the axillary space. The other two spaces are: q ...
. It is bounded by
teres major
The teres major muscle is a muscle of the upper limb. It attaches to the scapula and the humerus and is one of the seven scapulohumeral muscles. It is a thick but somewhat flattened muscle.
The teres major muscle (from Latin ''teres'', meaning ...
,
teres minor
The teres minor (Latin ''teres'' meaning 'rounded') is a narrow, elongated muscle of the rotator cuff. The muscle originates from the lateral border and adjacent posterior surface of the corresponding right or left scapula and inserts at both the ...
, medial border of the
humerus
The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...
, and long head of
triceps brachii
The triceps, or triceps brachii (Latin for "three-headed muscle of the arm"), is a large muscle on the back of the upper limb of many vertebrates
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with ba ...
.
They should not be confused with the true "axillary space" within the borders of the axilla.
Structure
Axilla
The true axilla is a conical space with its apex at the Cervico-axillary Canal, Base at the axillary fascia and skin of the armpit. When viewed in an axillary plane (axillary cut), it is more triangle with: Medial Wall: Serratus Anterior, Anterior Wall: pectoral muscles, Posterior Wall: subscapularis muscle, where the "apex" of the triangle is the humerus
Quadrangular space
This space is in the posterior wall of the axilla. It is a quadrangular space bounded laterally by surgical neck of the humerus, medially by long head of triceps brachii and inferiorly by
teres major
The teres major muscle is a muscle of the upper limb. It attaches to the scapula and the humerus and is one of the seven scapulohumeral muscles. It is a thick but somewhat flattened muscle.
The teres major muscle (from Latin ''teres'', meaning ...
. It is bounded superiorly by
subscapularis
The subscapularis is a large triangular muscle which fills the subscapular fossa and inserts into the lesser tubercle of the humerus and the front of the capsule of the shoulder-joint.
Structure
It arises from its medial two-thirds and
Som ...
in front, capsule of the shoulder joint in the middle, and behind by
teres minor
The teres minor (Latin ''teres'' meaning 'rounded') is a narrow, elongated muscle of the rotator cuff. The muscle originates from the lateral border and adjacent posterior surface of the corresponding right or left scapula and inserts at both the ...
. The
axillary nerve
The axillary nerve or the circumflex nerve is a nerve of the human body, that originates from the brachial plexus (upper trunk, posterior division, posterior cord) at the level of the axilla (armpit) and carries nerve fibers from C5 and C6. The a ...
and
posterior humeral circumflex artery
The posterior humeral circumflex artery (posterior circumflex artery, posterior circumflex humeral artery) arises from the third part of axillary artery at the lower border of the subscapularis, and runs posteriorly with the axillary nerve through ...
and vein pass through this space.
Triangular space
This space is also in the posterior wall of the axilla. It is a triangular space bounded medially by teres minor, laterally by long head of triceps brachii, and inferiorly by teres major. The
scapular circumflex artery
The circumflex scapular artery (scapular circumflex artery, dorsalis scapulae artery) is a branch of the subscapular artery and part of the scapular anastomoses.
It curves around the axillary border of the scapula, traveling through the anato ...
and scapular circumflex vein pass through this space.
Triangular interval
This space is in the inferior to the posterior wall of the axilla. The
triangular interval
The triangular interval (also known as the lateral triangular space, lower triangular space, and triceps hiatus) is a space found in the axilla. It is one of the three intermuscular spaces found in the axillary space. The other two spaces are: q ...
is bounded medially by long head of triceps brachii, laterally by medial border of humerus (some say the lateral head of the triceps), and superiorly by teres major. The
radial nerve
The radial nerve is a nerve in the human body that supplies the posterior portion of the upper limb. It innervates the medial and lateral heads of the triceps brachii muscle of the arm, as well as all 12 muscles in the posterior osteofascial comp ...
and
profunda brachii artery
The deep artery of arm (also known as arteria profunda brachii and the deep brachial artery) is a large vessel which arises from the lateral and posterior part of the brachial artery, just below the lower border of the teres major.
Structure
It ...
and vein passes through this space.
References
External links
Dissector Answers - Axilla & Arm* http://sarcoma.org/publications/OTOS_Book/13282_ON-13.pdf. This article defines the true "axillary space" in relation to Axillary Space Exploration and Resections.
{{Muscles of upper limb
Muscular system