Upper Limb Flashcards
What is the name of the thin sheet of fibrous tissue that connects the radius and ulnar and what aperture can be found within it?
Interosseous membrane
Contains the aperture for the interosseous artery
What 2 bones does the elbow joint involve an articulation between?
The humerus and the ulnar
What are the articular surfaces involved in the elbow joint?
Humero-ulna - between the trochlear of the humerus and the trochlear notch of the ulnar
What other articulation happens at the elbow and what are the articular surfaces involved?
Humero-radial - between the capitulum of the humerus and the upper surface of the radial head
The joint capsule of the elbow is continuous with what?
The joint capsule of the radio-ulnar joint
What is the deltopectoral triangle, and what runs along it?
Triangle between the deltoid, pectoralis major muscle and the clavicle, cephalic vein runs through it
What is the course of the cephalic vein in the upper limb?
Originates at the anatomical snuff box, passes laterally around the distal forearm to reach the anterolateral surface of the limb and then continues proximally. It crosses the elbow then passes up the arm into the deltopectoral triangle, in this depression the vein passes into the axilla by penetrating the deep fascia just inferior to the clavicle
What are the attachments and innervation of the pectoralis major muscle?
Origin
Clavicular head - anterior surface medial 1/2 of clavicle
Sternocostal head - ant. surface of sternum 1st 7 costal cartilages, sternal end of 6th rib, aponeurosis of external oblique
Insertion
Lateral lip of intertubercular sulcus on humerus
Innervation
Medial and lateral pectoral nerves (clavicular head, C5-6, Sternocostal head C6-T1)
What are the actions of the pectoralis major muscle?
Flexion, adduction and medial rotation of the arm at the glenohumeral joint,
Clavicular head - flexion of extended arm
Sternocostal head - extension of a flexed arm
What are the attachments and innervation of the pectoralis minor muscle?
Origin - anterior surfaces and superior borders of ribs 3-5, deep fascia overlying intercostal spaces
Insertion - Coracoid process of the scapula (medial border and upper surface)
Innervation - Medial pectoral nerve C5-T1
What are the actions of the pectoralis minor muscle?
Pulls tip of the shoulder down and protracts scapula
What are the attachments and innervation of the serratus anterior muscle?
Origin
Lateral surfaces of upper 8-9 ribs, and deep fascia overlying the intercostal spaces
Insertion
Costal surface of medial border of the scapula
Innervation
Long thoracic nerve C5-C7
What are the actions of the serratus anterior muscle?
Protraction and retraction of the scapula, keeps medial border and inferior angle of the scapula opposed to the thoracic wall
What are the attachments and innervation of the subclavius muscle?
Origin
1st rib at junction between rib and costal cartilage
Insertion
Groove on inferior surface of medial 1/3 of clavicle
Innervation
Nerve to subclavius C5, C6
What are the actions of the subclavius muscle?
Pulls tip of the shoulder down, pulls clavicle medially to stabilize the sternoclavicular joint
The axilla is shaped like a 4 sided pyramid, having 4 walls an apex and a base, what structures form the 4 walls?
Anterior wall - pectoralis major and minor, subclavius, calvipectoral fascia
Medial wall - Upper thoracic wall, serratus anterior muscle
Posterior wall - Subscapularis, teres major, latissiumus dorsi, long head of triceps brachii
Lateral wall - intertubercular sulcus
Through what part of the axilla does the neurovascular bundle enter limb after passing between the clavicle and the first rib? What does the neurovascular bundle contain?
Passes through the apex of the axilla
Contains the cords of the brachial plexus, the axillary artery and vein and lymph nodes
Axillary lymph nodes drain what percentage of lymph from the breast?
75%
Where does the lymph from the breast that drains into the axillary lymph nodes drain to?
Most drains to the anterior pectoral group but some goes to the posterior pectoral, central and apical nodes.
Pectoral nodes drain what part of the breast?
The lateral part of the breast
The central lymph nodes drain what part of the breast?
Drain the tail of the breast and collect lymph from other groups
Where does the apical group of lymph nodes receive lymph from and where does it lie?
The apical group receives lymph from all other groups and lies in the apex of the axilla
What are the 4 groups of axillary lymph nodes?
1) Central group
2) Apical group
3) Anterior pectoral group
4) Posterior pectoral group
Where do the parasternal nodes lie?
Anterior to the sternum
Where does pectoralis minor run in relation to the axillary artery?
Pectoralis minor runs anterior to the axillary artery
What the 3 cords of the brachial plexus and how are they arranged around the axillary artery?
1) Medial cord
2) Lateral cord
3) Posterior cord
Arranged as so around the axillary artery
What are the 4 terminal branches of the brachial plexus and what cords are they formed from?
1) Musculocutaneous nerve - lateral cord
2) Median nerve - lateral and medial cords
3) Ulnar nerve - medial cord
4) Radial nerve - posterior cord
Other than the median nerve, what other near-terminal branch is given off the posterior cord?
The axillary nerve
What is the root value of the musculocutaneous nerve?
C5-C7
What structures are innervated by the musculocutaneous nerve?
Motor - all muscles in the anterior compartment of the arm
Sensory - skin on lateral side of forearm
What is the root value of the axillary nerve?
C5,C6
What structures are innervated by the axillary nerve?
Motor - deltoid, teres minor
Sensory - skin over upper lateral part of arm
What is the root value of the median nerve?
(C5), C6 - T1
What structures are innervated by the median nerve?
Motor - all muscles in the anterior compartment of the forearm (except flexor carpi ulnaris and medial half of flexor digitorum profundus), 3 thenar muscles of the thumb and 2 lateral lumbrical muscles
Sensory - skin over the palmar surface of the lateral 3.5 digits, and over the lateral side of the palm and middle of the wrist
What is the root value of the radial nerve?
C5-T1
What structures are innervated by the radial nerve?
Motor - all muscles in the posterior compartment of the arm and forearm
Sensory - skin on the posterior aspects of the arm and forearm, the lower lateral surface of the arm and the dorsal lateral surface of the hand
What is the root value of the ulnar nerve?
C7-T1
What structures are innervated by the ulnar nerve?
Motor - all intrinsic muscles of the hand (except 3 thenar muscles and 2 lateral lumbricals), also flexor carpi ulnaris and flexor digitorum profundus in the forearm
Sensory - Skin over the palmar surface of the medial 1.5 digits and associated palm and wrist, and skin over the dorsal surface of the medial 1.5 digits
What land marks are used to define the beginning and the end of the axillary artery?
Subclavian artery becomes the axillary artery at the lateral margin of rib 1
Axillary artery becomes the brachial artery at the inferior margin of the teres major muscle
Where do the anterior and posterior circumflex humeral arteries arise from the axillary artery and what do they form?
Arise inferior to pectoralis minor and form an anastamosis around the surgical neck of the humerus via the quadrilateral space
Does the axillary artery lie medial or lateral to the axillary vein?
The axillary artery lies lateral to the axillary vein
At what landmarks does the axillary vein form?
Becomes the axillary vein at the lower border of teres major muscle
Becomes the subclavian vein at the lateral border of the first rib
Superficial veins return blood from where in the upper limb and drain into where?
Superficial veins drain blood from cutaneous structures and drain into deep veins, in the case of the upper limb, the axillary vein and brachial vein of the arm
What is the course of the basilic vein (a superficial vein) in the upper limb?
Arises on the ulanr (medial) side of the dorsal venous network of the hand. Passes vertically in the distal half of the arm, on the anteromedial surface, and penetrates deep fascia to assume a position medial to the brachial artery, then becomes the axillary vein at the lower border of teres major muscle
What is the course of the cephalic vein (a superficial vein) in the upper limb?
Arises at the radial (lateral) border of the dorsal venous network of the hand and passes superiorly on the anterolateral aspect of the arm, in the deltopectoral triangle and through the anterior wall of the axilla (travelling superficial to pectoralis minor) to drain into the axillary vein
What is the course of the median cubital vein in the upper limb?
Connects the basilic and cephalic vein and is often used for venepuncture, lies in the cubital fossal superior to the bicipital aponeurosis
What 3 clinical procedures are superficial veins used for?
1) Venepuncture
2) Transfusion
3) Catheterization
Which arteries branch from the axillary artery?
From superior to inferior
1) Superior thoracic artery - medially
2) Thoraco-acromial artery - anteriorly
3) Lateral thoracic artery - medially
4) Subscapular artery - medially
5) Anterior and posterior humeral circumflex arteries - laterally
6) Profunda brachii artery (actually comes off brachial artery) - laterally
What is meant by venae commitantes?
A pair of veins but occasionally more, that closely accompany an artery in such a manner that the pulsations of the artery aid venous return - makes for a more efficient circulatory system - usually found in the extremities of the arms and legs
What 2 morphological and functional compartments can the brachium be divided into by the deep brachial fascia of the arm?
1) Anterior or flexor compartment
2) Posterior of extensor compartment
What is the name of the 2 parts of deep brachial fascia either side of the humerus in the arm?
Lateral intermuscular septum
Medial intermuscular septum
What are the 3 muscles of the anterior/flexor compartment of the arm and what is the common nerve supply to these muscles?
1) Biceps brachii
2) Brachialis
3) Coracobracialis
Common nerve supply = musculocutaneous nerve
What artery supplies the anterior compartment of the arm, describe its course?
Brachial artery
Begins as a continuation of the axillary artery at the lower border of teres major, terminates just distal to the elbow joint where it divides into the radial and ulnar arteries, proximal arm it lies on the medial side in the distal arm it moves laterally to assume a position midway between the lateral and medial epicondyles, crosses anteriorly to the elbow joint where it lies immediately medial to the tendon of biceps brachii
What are the attachments of the biceps brachii muscle?
Origin
Short head - apex of the coracoid process
Long head - supraglenoid tubercle of scapula
Insertion - Radial tuberosity
What are the actions of biceps brachii muscle?
Powerful flexor of the forearm at the elbow joint and supinator of the forearm, accessory flexor of the arm at the glenohumeral joint
What are the attachments of brachialis muscle?
Origin
Anterior aspect of the humerus (medial and lateral surfaces) and adjacent intermuscular septae
Insertion
Tuberosity of ulnar
What are the actions of brachialis muscle?
Powerful flexor of the forearm at the elbow joint
What are the attachments of the coracobrachialis muscle?
Origin - apex of coracoid process
Insertion - Linear roughening on midshaft of humerus on medial side
What are the actions of the coracobrachialis muscle?
Flexor of the arm at the glenohumeral joint
What is the one muscle of the posterior compartment of the arm?
Triceps brachii
What are the attachments of triceps brachii?
Origin
Long head - infraglenoid tubercle of scapula
Lateral head - posterior surface of humerus, superiorly and laterally to the spiral groove
Medial head - posterior surface of humerus, inferiorly and medially to the spiral groove
Insertion
Olecranon
What is the nerve supply to triceps brachii?
Radial nerve C6-C8
What is the function of triceps brachii?
Extension of forearm at elbow joint, long head can also extend and adduct the arm at the shoulder joint
Where does the deltoid tuberosity lie in relation to the spiral groove?
Laterally
Which 2 structures run in the spiral groove?
Radial nerve
Profunda brachii artery
Which artery supplies the posterior compartment of the arm, describe its course?
Profunda brachii artery
Enters posterior compartment together with radial nerve and together they pass through the triangular interval, pass along the spiral groove deep to the lateral head of the triceps brachii
Branches of it supply adjacent muscles and anastamose with the posterior circumflex humeral artery. The artery terminates as 2 collateral vessels which contribute to the anastomotic network of vessels around the elbow joint
What are the 2 superficial muscles of the back?
Deltoid and trapezius
Which muscle crosses teres major?
Long head of triceps brachii
Which nerve supplies deltoid?
Axillary nerve
What is the name of the groove between pectoralis major and deltoid?
Deltopectoral groove
Which vein runs in the deltopectoral groove?
Cephalic vein
Which muscle overlies the brachial plexus in the axilla?
Pectoralis minor
Does the axillary vein lie medial or lateral to the axillary artery?
Medial
Which artery supplies the 3 muscles in the anterior compartment of the arm and where does it arise from?
Brachial artery
Where axillary artery crosses the inferior border of teres major it becomes the brachial artery
What are the 3 heads of triceps brachii?
Long head
Lateral head
Medial head
