The apex of the pyramid is formed by the first rib, the subclavius muscle, and the collar bone, at the side of the lowest part of the neck. The floor of the axilla is tough axillary fascia that connects the thoracic wall, the gleno-humeral joint, and the posterior part of the axilla.
Full Answer
Which muscle contribute to anterior wall of axillary cavity?
The pectoralis major and minor muscles make up the anterior wall. The clavicle, scapula, and first rib comprise the superior wall. The posterior wall is the teres major, subscapularis, and latissimus dorsi muscles.
What is the axillary fascia?
The axillary fascia is relatively dense, especially in the central third of the shoulder and below the deltoid muscle. It divides at the lateral margin of the latissimus dorsi muscle into two layers, which ensheaths the muscle and are attached posteriorly to the spinous processes of the thoracic vertebrae.
What is the axillary region of the body?
The axilla (also, armpit, underarm or oxter) is the area on the human body directly under the joint where the arm connects to the shoulder. It also contains many sweat glands. In humans, the formation of body odor happens mostly in the armpit.
What muscles make up the axilla?
The axilla is filled with adipose (fat) and allows passage for: vessels, nerve plexus, lymphatics, and muscles. The muscles include the coracobrachialis, pectoralis minor, and the biceps brachii. The posterior border of pectoralis major and minor defines the anterior border (fold).
Where is the axillary fascia located?
axillaThe pectoral fascia is very thin over the upper part of the Pectoralis major, but thicker in the interval between it and the Latissimus dorsi, where it closes in the axillary space and forms the axillary fascia. Axillary fascia, together with the skin, forms the base of the axilla.
What does fascia mean in anatomy?
Introduction. Fascia is made up of sheets of connective tissue that is found below the skin. These tissues attach, stabilize, impart strength, maintain vessel patency, separate muscles, and enclose different organs.
Where is the axillary nerve in the armpit?
The axillary nerve, which is also called the circumflex nerve, emerges from the posterior cord of a network of nerves called the brachial plexus right at the level of the armpit.
Is the axillary part of the arm or trunk?
Introduction. The axilla is an anatomical region under the shoulder joint where the arm connects to the shoulder. It contains a variety of neurovascular structures, including the axillary artery, axillary vein, brachial plexus, and lymph nodes.
Which muscle can be palpated at the anterior border of the axillary space?
Anterior border: pectoralis major and pectoralis minor muscles. Posterior border: subscapularis, latissimus dorsi, and teres major muscles. Superior border: clavicle, scapula, and the first rib.
What structure is used to divide the axillary artery into its three parts?
As it passes through the axilla, the artery is divided into three parts by pectoralis minor, as the muscle travels superolaterally from its origin at the 3rd, 4th and 5th ribs to its insertion on the medial aspect of the coracoid process. Conveniently, each segment gives off a corresponding number of branches.
What forms the anterior axillary fold?
The anterior axillary fold is formed by the lateral edge of the pectoralis major muscle; the posterior axillary fold is formed by the lateral edges of the latissimus dorsi and teres major muscles.
What are the axillary lymph nodes?
Lymphatic system and axillary nodes Lymph nodes are small clumps of immune cells that act as filters for the lymphatic system. They also store white blood cells that help fight illness. The lymph nodes in the underarm are called axillary lymph nodes. If breast cancer spreads, this is the first place it's likely to go.
What is the prevertebral fascia?
The prevertebral fascia extends medially behind the carotid vessels, where it assists in forming their sheath, and passes in front of the prevertebral muscles. The prevertebral fascia is fixed above to the base of the skull, and below it extends behind the esophagus into the posterior mediastinal cavity of the thorax.
What is a deep fascia?
Deep fascia is a dense connective tissue that is commonly arranged in sheets that form a stocking around the muscles and tendons beneath the superficial fascia (1).
Is pectoral fascia a deep fascia?
At the lower part of the thoracic region the deep fascia is well-developed, and is continuous with the fibrous sheaths of the rectus abdominis....Pectoral fasciaTA22317FMA37803Anatomical terminology5 more rows
What is the function of suspensory ligament of axilla?
It passes inferolaterally to attach firmly to the axillary fascia that forms the floor of the axilla. Its seems to function to apply tension to the axillary fascia and more superficial skin. In doing so, it creates the concavity associated with the axillary floor.
Where is the axillary vein?
Dr. Ali is also an award-winning writer. The axillary vein is a major vein in the upper body that carries blood from the upper limb, armpit, and the upper side of the chest wall towards the heart. On each side of the body, it forms where the basilic and brachial veins join in the axilla, a space just below the shoulder that allows arteries, veins, ...
What are the tributaries of the axillary artery?
These are: Thoracoacromial vein. Lateral thoracic vein. Subscapular vein. Anterior circumflex. Humeral vein. Posterior circumflex humeral vein 5 .
How many centimeters are in axillary veins?
The body has an axillary vein on each side, typically varying between 1.1 and 1.2 centimeters (cm) in diameter. 3 Veins are typically a little thinner than arteries, which are the vessels that carry blood away from the heart. They consist of three layers:
Which veins join together to form the axillary vein?
Along its course are several important features: Origin: The basilic vein, a primary surface (“superficial”) vein of the arm, and the brachial vein, one of the upper arm’s deep veins, join together to form the axillary vein. Axillary region: The axillary vein travels upwards and towards the middle of the body, crossing the armpit.
Where do the basilic and brachial veins join?
On each side of the body, it forms where the basilic and brachial veins join in the axilla, a space just below the shoulder that allows arteries, veins, and nerves to pass. Its course is relatively short as it moves upwards towards the middle of the body and terminates into the subclavian vein at the border of the first (topmost) rib. 1 .
Where does the cephalic vein terminate?
This occurs at the border of the top-most rib. 1
What is the inner lining of the veins?
Tunica intima: The inner lining of veins is composed of a layer of flat cells, called squamous epithelium, in contact with a base membrane that keeps blood inside.
What are the contents of the axilla region?
The contents of the axilla region include muscles, nerves, vessels, and lymphatics: Axillary artery (and branches) – the main artery supplying the upper limb. It is commonly referred as having three parts; one medial to the pectoralis minor, one posterior to pectoralis minor, and one lateral to pectoralis minor.
Where is the axilla located?
The axilla is the name given to an area that lies underneath the glenohumeral joint, at the junction of the upper limb and the thorax. It is a passageway by which neurovascular and muscular structures can enter and leave the upper limb. In this article, we shall examine the anatomy of the axilla – the borders, contents, ...
What structures pass through the axillary nerve?
Structures passing through include the axillary nerve and posterior circumflex humeral artery (a branch of the axillary artery. The last passageway is the clavipectoral triangle, which is an opening in the anterior wall of the axilla. It is bounded by the pectoralis major, deltoid, and clavicle.
What is axillary lymph node enlargement?
Axillary lymph node enlargement is a non-specific indicator of breast cancer. Biceps brachii (short head) and coracobrachialis – these muscle tendons move through the axilla, where they attach to the coracoid process of the scapula. By TeachMeSeries Ltd (2021) Fig 3 – Contents of the axilla region.
What is the shape of the axillary inlet?
Borders. The overall 3D shape of the axilla looks slightly like a pyramid. It consists of four sides, an open apex and base: Apex - also known as the axillary inlet, it is formed by lateral border of the first rib, superior border of scapula, and the posterior border of the clavicle.
How many borders does the right axilla have?
Fig 1 – Anterior view of the right axilla region. Note the pyramidal shape, with 6 borders (or sides).
Which part of the axillary artery drains lymph from the upper limb?
The lateral part of the axillary artery travels through the axilla. The axillary lymph nodes drain lymph from the upper limb only. The apex of the axilla is markedly decreased in size with arm adduction. The lateral border of the axilla is formed by the intertubercular sulcus of the humerus.
What is the axillary structure?
The axilla is a pyramidal compartment between the upper extremity and the thoracic walls ( Fig. 2.8). It is described as having four walls, an apex, and a base. The curved base is made of axillary fascia and skin. Externally, this region, the armpit, appears dome-shaped (and covered with hair after puberty). The apex is not a roof but an aperture that extends into the posterior triangle of the neck through the cervicoaxillary canal. The cervicoaxillary canal is bounded anteriorly by the clavicle, posteriorly by the scapula, and medially by the first rib. Most structures pass through the cervical axillary canal as they course between the neck and upper extremity. The anterior wall is made up of the pectoralis major and minor muscles and their associated fasciae. The posterior wall is composed primarily of the subscapularis muscle, located on the anterior surface of the scapula, and to a lesser extent by the teres major and latissimus dorsi muscles and their associated tendons. The lateral wall is a thin strip of the humerus, the bicipital groove, between the insertions of the muscles of the anterior and posterior walls. The medial wall is made up of serratus anterior muscle that covers the thoracic wall in this region (over the upper four or five ribs and their associated intercostal muscles).
Which muscle group is more likely to be involved in compression neuropathies?
Classically, more muscles have been described in this region than in the axillary and brachial regions: the anconeus epitrochlear (AE), Gantzer (GM), and variant palmar (APLM) muscles. They have potential implications in compression neuropathies.
Which muscle is inserted into the medial epicondyle?
Amongst the many muscles that are not commonly found in the upper limb, lies the chondroepitroclear muscle, which arises from the ventral edge of the pectoralis major muscle, the osteochondral junction of the fifth and sixth costal cartilage or the aponeurosis of the external oblique muscle, and is inserted into the medial intermuscular septum or the medial epicondyle after crossing the armpit and upper arm [ 10–12]. It appears as a very long and narrow slide applied closely to the inferolateral margin of the sternocostal head of the pectoralis major muscle. It curves away from the pectoralis major, takes an arcuate course while remaining tied to the axillary fascia, descends almost vertically distally along the medial aspect of the arm, and continues into an elongated thin tendon extending posteriorly to the ulnar nerve [13 ]. Therefore, its clinical relevance may be related to entrapment of the ulnar nerve as a possible result of compression by the abnormal muscle [ 14 ].
Can brachial plexus injuries occur in flank position?
Despite vigilant attention to patient positioning, injuries to the brachial plexus may occur during procedures in the flank position. Injuries to the brachial plexus of the downside arm during flank positioning, for example, are most often compressive, although stretch injuries may occur if the dependent arm shifts position during the surgical procedure. 81 Brachial plexus injuries of the upside arm in the flank position, meanwhile, are most often the result of abduction, extension, and external rotation of the humerus that stretch the plexus around the clavicle, the tendon of the pectoralis minor, and the head of the humerus. 84
Which fascia is thicker, the pectoral or the axillary?
Axillary fascia. The pectoral fascia is very thin over the upper part of the Pectoralis major, but thicker in the interval between it and the Latissimus dorsi, where it closes in the axillary space and forms the axillary fascia. Axillary fascia, together with the skin, forms the base of the axilla.
Which part of the pectoral fascia is thicker?
The pectoral fascia is very thin over the upper part of the Pectoralis major , but thicker in the interval between it and the Latissimus dorsi, where it closes in the axillary space and forms the axillary fascia. Axillary fascia, together with the skin, forms the base of the axilla.
Where is the pectoral fascia?
The pectoral fascia is a thin lamina, covering the surface of the Pectoralis major, and sending numerous prolongations between its fasciculi: it is attached, in the middle line, to the front of the sternum; above, to the clavicle; laterally and below it is continuous with the fascia of the shoulder, axilla, and thorax.
What is the lamina of the armpit?
The hollow of the armpit, seen when the arm is abducted, is produced mainly by the traction of this fascia on the axillary floor, and hence the lamina is sometimes named the suspensory ligament of the axilla.
What is the hollow of the armpit?
The hollow of the armpit, seen when the arm is abducted, is produced mainly by the traction of this fascia on the axillary floor, and hence the lamina is sometimes named the suspensory ligament of the axilla.
When was Gray's anatomy published?
This definition incorporates text from a public domain edition of Gray's Anatomy (20th U.S. edition of Gray's Anatomy of the Human Body, published in 1918 – from http://www.bartleby.com/107/).
What is the axilla?
The axilla is an anatomical region under the shoulder joint where the arm connects to the shoulder. It contains a variety of neurovascular structures, including the axillary artery, axillary vein, brachial plexus, and lymph nodes. There are five anatomic borders of the axilla: the superior, anterior, posterior, lateral, and medial walls.
What are the five anatomic borders of the axilla?
There are five anatomic borders of the axilla: the superior, anterior, posterior, lateral, and medial walls. The medial wall is the serratus anterior and the first four ribs. The humerus, the coracobrachialis, and the short head of the biceps form the lateral wall. The pectoralis major and minor muscles make up the anterior wall.
Which artery supplies the axillary?
The primary blood supply to the axilla is the axillary artery, which branches directly off of the subclavian artery. The axillary artery is also a major blood supplier to the shoulder and upper arm.
What muscles make up the anterior wall?
The pectoralis major and minor muscles make up the anterior wall. The clavicle, scapula, and first rib comprise the superior wall. The posterior wall is the teres major, subscapularis, and latissimus dorsi muscles. The primary blood supply to the axilla is the axillary artery, which branches directly off of the subclavian artery. ...
What is axilla ?
The axilla or armpit is a fat-filled pyramid-shaped space, between the upper part of the arm and the side of the chest wall. It contains the brachial plexus, axillary vessels, and lymph nodes.
What is the canal between the neck and axilla?
It is also called the cervico-axillary canal, triangular in shape. It is a passageway between the neck and axilla.
What fold is in front of the pectoralis?
In front by anterior Axillary fold, formed by the lower border of the pectoralis major muscles.
What causes axillary nodes to enlarge?
An infection in the upper limb can cause the axillary nodes to enlarge and become tender and inflamed, a condition called lymphangitis
Which fold is the inferior most part of the anterior?
It is formed by the pectoralis major and pectoralis minor, subclavius. The anterior axillary fold is the inferior most part of the anterior formed by the pectoralis major.
Where is the anterior group of the pectoral vein?
Anterior or pectoral group: lie along the lateral thoracic vein at the lower border of the pectoralis minor.