Axilla, upper extremity vasculature, cubital fossa, forearm bones and elbow joint Flashcards
What is the four-sided pyramid-shaped region that contains neurovascular structures that pass through the shoulder region?
axilla
What are the neurovascular structures that pass through the axilla enclosed in?
a fascia sleeve called the axillary sheath
What is the axillary sheath a direct continuation of?
the prevertebral fascia of the neck
The axilla is a passage way from the neck to the _____
arm
How many boundaries does the axilla have?
6:
base (floor)
apex (inlet)
anterior wall
posterior wall
medial wall
lateral wall
What forms the base of the axilla?
axillary fascia and skin of armpit
What forms the apex of the axilla?
passageway for structures entering/leaving the shoulder and arm; bounded by the first rib, clavicle, and superior part of scapula
What forms the anterior wall of the axilla?
pectoralis major and minor muscles & clavipectoral fascia
What forms the posterior wall of the axilla?
subscapularis, teres major, latissimus dorsi, and long head of the triceps muscle
What forms the medial wall of the axilla?
upper rib cage and intercostal and serratus anterior muscles
What forms the lateral wall of the axilla?
humerus (intertubercular sulcus)
What are the important structures in the axilla?
- axillary artery
- axillary vein(s)
- axillary lymph nodes
- branches of brachial plexus
- biceps and the coracobrachialis muscle
- axillary tail (of Spence)
How many parts is the axillary artery divided into?
3
How many major collections of nodes are embedded in the axilla?
5 major nodes
What is the extension of the female breast’s upper outer quadrant called?
axillary tail (of Spence)
What does the axillary sheath contain and not contain?
Contains the axillary artery and 3 cords of the brachial plexus
-does not contain the axillary lymph nodes
-sometimes contains the axillary vein
What does adipose tissue provide?
protection, cushioning, thermal regulation, gives off hormones, energy storage
The axillary sheath keeps everything in place and decreases the risk of what?
infection by preventing invaders
What are the 5 lymph node groups in the axilla that are named to reflect their relationship to axillary structures?
- pectoral nodes
- humeral (lateral) nodes
- subscapular nodes
- central nodes
- apical nodes
Where can you find pectoral nodes?
deep to the pectoralis major muscle
What do the pectoral nodes do?
drain the lateral and anterior chest wall, mammary glands, and upper abdominal wall
Where can you find the humeral (lateral) nodes?
on the lateral wall of the axilla
What do the humeral (lateral) nodes do?
receive lymph from the upper limb
Where are the subscapular nodes located?
posterior wall of the axilla
What do the subscapular nodes do?
drain the back muscles
Where are the central nodes located?
along the axillary vessels
What do the central nodes do?
receive lymph from the lateral quadrants of the breast
Where are the apical nodes located?
at the apex of the axilla and continuous with the inferior deep nodes (deep neck)
What do the apical nodes do?
drain the other axillary nodes and structures in the deep neck region
Which nodes are most important and why?
pectoral nodes because they control most of the drainage from the breast
If you remove too many lymph nodes, what condition can this lead to?
lymphedema
What do mammary glands drain into?
clavicular nodes
The axillary artery is the distal continuation of what artery?
subclavian artery
Where does the axillary artery begin?
at the first rib
The axillary artery is divided into 3 descriptive parts by the anterior presence of what muscle?
pectoralis minor muscle
What does the axillary artery continue as distally at the level of the inferior border of the teres major muscle?
continues as the brachial artery
When does the axillary artery stop being called the axillary artery and begins being called the brachial artery?
inferior border of teres major
Where is the 1st segment of the axillary artery located?
between the lateral border of the 1st rib and the medial border of the pectoralis minor
What artery branches off the axillary artery in the 1st segment?
superior thoracic artery
Where is the second segment of the axillary artery located?
Lies posterior to the pectoralis minor
How many branches does the 2nd segment of the axillary artery have?
2
What are the 2 arteries that branch off the 2nd segment of the axillary artery called?
thoracoacromial artery (passes medially to pec minor)
lateral thoracic artery (passes laterally to pec minor)
Where is the 3rd segment of the axillary artery located?
extends from lateral border of the pectoralis minor to inferior border of teres major
How many branches does the 3rd segment of the axillary artery have?
3
What are the 3 arteries that branch off the 3rd segment of the axillary artery called?
subscapular artery
anterior circumflex humeral artery
posterior circumflex humeral artery
What is the largest branch of the axillary artery?
subscapular artery
What does the superior thoracic artery supply blood to?
the first and second intercostal spaces
What does the thoracoacromial artery do?
wraps around proximal border of the pectoralis minor muscle and gives rise to pectoral, acromial, clavicular, and deltoid branches
What does the lateral thoracic artery course with and what does it do?
the long thoracic nerve along the lateral surface of the serratus anterior muscle where it supplies this muscle and surrounding tissue
What artery supplies blood to the serratus anterior muscle?
lateral thoracic artery
What does the thoracoacromial artery supply blood to?
bone and muscle
What does the subscapular artery course along?
the anterior surface of the subscapularis muscle
What does the subscapular artery give rise to?
circumflex scapular artery
thoracodorsal artery
What does the circumflex scapular artery do?
traverses the triangular space to the posterior side of the scapular
What does the circumflex scapulary artery form an anastomosis with?
the suprascapular and dorsal scapular arteries
What does the thoracodorsal artery course with?
thoracodorsal nerve
What does the thoracodorsal artery supply blood to?
the latissimus dorsi muscle
What does the anterior humeral circumflex artery do?
wraps anteriorly around the surgical neck of the humerus and forms an anastomosis with the posterior humeral circumflex artery
What does the posterior humeral circumflex artery do?
traverses the quadrangular space with the axillary nerve, wraps posteriorly around the surgical neck of the humerus, an forms an anastomoses with the anterior humeral circumflex artery
Where does the axillary vein lie?
initially (distally) on the anteromedial side of axillary artery, with its terminal part antero-inferior to the artery
What is the axillary vein formed by?
the union of the accompanying brachial veins and the basilic vein at the inferior border of the teres major
Where does the axillary vein end?
the lateral border of the 1st rib
At the lateral border of the 1st rib, what does the axillary vein become?
the subclavian vein
What is the main arterial supply to the arm and is the continuation of the axillary artery?
brachial artery
Where does the brachial artery begin?
inferior border of the teres major
Where does the brachial artery end?
ends in the cubital fossa opposite the neck of radius under cover of the bicipital aponeurosis
What does the brachial artery divide into?
radial and ulnar arteries
Where does the brachial artery lie?
anterior to the triceps and brachialis
During its inferolateral course, the brachial artery accompanies what?
the median nerve
What are the main branches of the brachial artery that arise from its medial aspect?
profunda brachii artery (deep artery of the arm)
superior and inferior ulnar collateral arteries
What are the main superficial veins of the arm?
cephalic and basilic veins
What are the cephalic and basilic veins formed from?
the lateral and medial ends of the dorsal venous network of the hand
What is the course of the cephalic vein?
ascends lateral to biceps brachii (on anterior surface) and then enters deltopectoral groove, and then pierces the fascia in the deltopectoral triangle to enter the axillary vein
What is the deltopectoral groove formed by?
the adjacent deltoid and pectoralis muscles
What does the cephalic vein drain into?
axillary vein
What is the course of the basilic vein?
ascends medial to biceps brachii (on medial surface) and accompanies the brachial artery to the axilla, where it joins the brachial vein, which then becomes the axillary vein at the inferior border of the teres major muscle
What does the basilic vein drain into?
brachial vein
The lymphatic drainage of the arm is to what?
the cubital and axillary lymph nodes
What is the cubital fossa important for?
communicating with the arm to the forearm
What is the superior border of the cubital fossa?
line between epicondyles
What is the medial border of the cubital fossa?
pronator teres
What is the lateral border of the cubital fossa?
brachioradialis
What structure(s) make up the floor of the cubital fossa?
mainly brachialis and supinator mm
What structure(s) make up the roof of the cubital fossa?
deep fascia, bicipital aponeurosis
What are the contents of the cubital fossa?
- terminal part of brachial artery and commencement of its terminal branches (radial and ulnar aa)
- (deep) accompanying veins of the arteries
- biceps brachii tendon
- median nerve
- radial n., dividing into superficial and deep branches
What does the brachial artery lie between in the cubital fossa?
between the biceps tendon and median nerve
Why is the cubital fossa clinically important?
contains the brachial a. and accompanying veins, the median nerve, and superficial veins commonly used for venipuncture
The superficial fascia of the cubital fossa contains a variable arrangement of superficial veins as well as what?
the medial and lateral cutaneous nerves of the forearm
Is the cephalic vein medial or lateral?
laterial
Is the basilic vein medial or lateral?
medial
What joins the cephalic and basilic vein?
the median cubital vein
What vein ends in the median cubital vein?
median vein of the forearm
What is the stabilizing bone of the forearm?
ulna
Of the 2 forearm bones, which is the medial and longer bone?
ulna
What projections of the ulna form the trochlear notch?
olecranon posteriorly and coronoid process anteriorly
Inferior to the coronoid process of the ulna is what?
tuberosity of the ulna (ulnar tuberosity)
On the lateral side of the coroniod process of the ulna is a smooth, rounded concavity, called the ____
radial notch
What does the radial notch articulate with?
head of the radius
Does the ulna articulate with the carpal bones?
no
What separates the ulna bone from the carpals?
a fibrocartilaginous articular disc
What type of joint does the ulna form at the elbow?
a hinge joint
What bone is lateral in the forearm?
radius
What does the radius articulate with?
the capitulum of the humerus, ulna, and scaphoid
What bone is primarily a bone of movement in the forearm during rotation relative to the fixed ulna?
radius
What landmark on the radius is a disc-shaped structure that enables the synovial pivot joint in the forearm?
head of the radius
What landmark on the radius is a swelling inferior to the radial neck on the medial surface where the biceps brachii muscle attaches?
radial tuberosity
What landmark on the radius is a prominent and palpable process on the distal and lateral end where the brachioradialis muscle attaches?
radial styloid process
What landmark on the radius accommodates the head of the ulna?
ulnar notch
What is the name of the joint found between the radius bone and carpals?
radiocarpal joint
The articulations of the radius, ulna, and humerus result in how many separate joints?
3
What do the 3 elbow joints share?
synovial cavity
What do the 3 elbow joints enable the forearm to do?
to flex, extend, pronate, and supinate on the humerus
What are the names of the 3 elbow joints?
- humeroulnar joint
- humeroradial joint
- proximal radioulnar joint
What elbow joint allows for articulation between the humerus (trochlea) and the ulna (trochlear notch)?
humeroulnar joint
What joint allows for articulation between the humerus (capitulum) and radius (head)?
humeroradial joint
What movements does the humeroulnar and humeroradial joint allow for?
flexion: bending of the elbow
extension: straightening of the elbow
What main muscles and nerve allow for flexion at the elbow?
biceps brachii, brachialis
musculocutaneous nerve
What are the main muscles and nerve that allow for extension of the elbow?
triceps brachii
radial nerve
What joint allows for articulation between the radius (head) and ulna (radial notch)
proximal radioulnar joint
What actions does the proximal radioulnar joint allow for?
pronation: pivoting the elbow into prone position (palms down)
supination: pivoting elbow into supine position (palms up)
What main muscles and nerve allows for pronation of the forearm?
pronator teres
median nerve
What main muscle and nerve allows for supination of the forearm?
biceps brachii muscle
musculocutaneous nerve
What two things provide support for the elbow?
capsule
ligaments
The humeroulnar, humeroradial, and proximal radioulnar joints are all enclosed in what?
a single capsule
The joint capsule of the elbow is loose, which accommodates for what?
high degree of motion
What is the joint capsule of the elbow reinforced by?
ligaments
Most hinge joints in the body (including humeroulnar joint) contain what type of ligaments to enhance medial and lateral stability?
medial and lateral collateral ligaments
What ligament in the elbow joint provides medial stability of the elbow complex; resists valgus forces; and prevents gapping of the joint medially?
ulnar collateral (medial collateral) ligament
Where do the fibers run in the ulnar collateral (medial collateral) ligament of the elbow joint?
fibers run from the medial epicondyle of the humerus to the proximal ulna
What ligament in the elbow joint provides lateral stability of the elbow complex; resists varus forces; and prevents gapping of the joint laterally?
radial collateral (lateral collateral) ligament
Where do the fibers run in the radial collateral (lateral collateral) ligament of the elbow joint?
fibers run from lateral epicondyle to the annular ligament of the olecranon process of the ulna
What are the ligaments that support the elbow joint?
-ulnar collateral (medial collateral) ligament
-radial collateral (lateral collateral) ligament
-annular ligament
What movement is varus movement?
outward movement
What movement is valgus movement?
inward movement
What is the circular ligament attached to the anterior and posterior surfaces of the radial notch of the ulna and forms a ring that encompasses the radial head?
annular ligament
The inner surface of the annular ligament is covered with cartilage and provides stability for what joint?
humeroulnar joint
What does the annular ligament of the elbow joint help provide stability for?
supination and pronation
What is the most important bursa associated with the elbow complex?
olecranon bursa
Where is the olecranon bursa located?
between the capsule of the elbow complex and the triceps tendon
What does the olecranon bursa do?
diminishes friction between capsule of the elbow complex and triceps tendon as they cross over each other
What are the contents of the cubital fossa from medial to lateral?
median nerve, brachial artery, biceps brachii tendon, and radial nerve