Upper Limb Part 1 Flashcards
The axillary region of the upper limb is bound by
Apex, base and 4 walls
Apex is the cervico-axillary canal: passageway from neck to axilla
Muscles, vessels and innervation of the anterior compartment of the arm are the
Muscles of the posterior compartment of the arm are the
Flexors, brachial artery, musculocutaneous nerve
Extensors, deep brachial artery, radial nerve
The cubital fossa boundaries
Triangular depression on anterior surface of elbow
Lateral- brachioradialis m
Superior- line from medial epicondyle to lateral epicondyle
Medial- pronator teres m
Cubital fossa contents
And what superficial vein passes over the cubital fossa?
End of the brachial artery
Tendon of biceps brachii m
Median nerve
Radial nerve
Median cubital vein
Anterior compartment of the forearm muscles, vessels, innervation
Flexors and pronators
Radial and ulnar aa
Median and ulnar n
Posterior compartment of the forearm muscles, vessels, innervation
Extensors and supinators
Posterior interosseus a
Radial n
The carpal tunnel
Tunnel between carpal bones (floor/walls) and flexor retinaculum (roof)
It contains the tendons of: flexor digitorum profundus, flexor digitorum superficialis, flexor pollicis longus
Contains the median nerve
Clinical relevance: Pressure in tunnel can compress the median nerve
What travels in the radial groove of the humerus
The radial nerve and deep artery of the arm travel in the radial groove. Both structures are susceptible to damage with a mid shaft numeral fracture
Hand joints
Carpometacarpal joint Metacarpophalangeal joint Proximal interhphalangeal joint Interphalangeal joint Distal interphalangeal joint
Muscles of the anterior chest wall
Pectoralis major- clavicle are head and eternal head
Subclavius
Pectoralis minor
Lateral chest wall muscles
Serratus anterior- attaches to the entire anterior aspect of the medial border of the scapula. It is the only pronator of the scapula. Damage to this muscle or the nerve supplying it (long thoracic n) will lead to unopposed retraction of the scapula
Upper Limb- anterior arm muscles
Biceps brachii- long (lateral side) and short head
Brachialis
Coracobrachialis
Proximal attachment of most superficial muscles in the forearm is the
Flexors muscles attach to
Extensor muscles attach to
Distal end of the humerus Medial side (flexors=anterior compartment) Lateral side (extensors=lateral compartment)
First layer muscles of the forearm
Brachioradialis, pronator teres, flexor carpi radialis, palmaris longus, flexor carpi ulnaris
Second layer of the muscles in the forearm
Flexor digitorum superficialis
Third layer muscles in the forearm
Flexor digitorum profundus
Flexor pollicis longus
Fourth layer muscles in the forearm
Pronator quadratus
Difference between flexor digitorum superficialis and flexor digitorum profundus
The distal attachment points of the flexor digitorum superficialis are the shafts of the MIDDLE phalanges and their tendons split as they attach to the bone
Emerging from underneath these tendons are the tendons of the flexor digitorum profundus
Because BOTH muscles cross the proximal interphalangeal joint, both assist in flexing that joint. However, the only muscle that crosses the DIP and thus flexes that joint is the flexor digitorum profundus
The subclavian artery becomes what after it crosses:
Becomes the axillary artery after it crosses the lateral border of the first rib
The axillary artery can be divided into:
Eventually becomes:
3 segments
1st part- between 1st rib and the medial border of pectoralis minor m
2nd- behind the pectoralis minor and ending at the lateral border of the pectoralis minor m
3rd- extending to the inferior border of the teres major m
Becomes the brachial artery
Each of the 3 segments of the axillary artery has smaller branches. Branches of the first segment of the axillary artery:
Superior thoracic artery
Branches of the subclavian artery
Thryocervical trunk becomes the transverse cervical artery which has branches that contribute to the anastomoses around the scapula- dorsal scapular a and the suprascapular a (these two arteries anastomoses with the circumflex scapular artery at the back of the scapula)
Branches of the second part of the axillary artery
Thoracoacromial artery (divides into deltoid, pectoral, clavicular and acromial branches) Lateral thoracic artery
Branches of the third part of the axillary artery
Posterior circumflex humeral artery and the anterior circumflex humeral artery (these two anastomose around the humerus) Subscapular artery (branches into the thoracodorsal artery and the circumflex scapular artery)
Clinical correlation with the surgical neck fracture of the humerus
The posterior circumflex humeral artery travels with the axillary nerve near the surgical neck
The thoracodorsal artery travels with
The thoracodorsal nerve to the latissimus Dorsi muscle
The axillary artery becomes the brachial artery after
It crosses the inferior border of the teres major muscle
Brachial artery, along with its branches, supply blood to the upper limb
Branches of the brachial
Deep brachial artery (gives off the radial collateral artery)- travels with the radial nerve in the radial groove on the posterior aspect of the shaft of the humerus
Superior ulnar collateral artery (usually travels along the ulnar nerve)
Inferior ulnar collateral artery
The brachial artery splits near the
Cubital fossa into the ulnar and radial branches that anastomose with the branches coming of the brachial artery
Anastomoses around the elbow allow
Blood flow to the forearm even if the brachial artery is blocked in/near the cubital region
Branch of the radial artery
Branches of the ulnar artery
Radial recurrent artery (connects to the radial collateral a)
Anterior and posterior ulnar recurrent arteries (connects with the superior and inferior ulnar collateral arteries, resp.)
Common interosseus artery (divides into the anterior and posterior interosseus arteries)
Veins in the upper limb have the same names and travel with their arteries (blood flowing in opposite direction) except for
Superficial veins on the upper limb do NOT have paired arteries
Superficial veins of the upper limb
Basilic v, cephalic v, median cubital v
The basilic vein travels
Along the medial aspect of the forearm and arm
It pierces the brachial fascia in the middle of the arm and runs parallel to the brachial artery.
It merges superiorly with deep veins in the arm to form the axillary vein
The cephalic vein travels
Along the lateral aspect of the forearm and arm, connecting to the axillary vein in the shoulder
The median cubital vein tract
Branch that connects the cephalic and basilic veins in the cubital region. It is a common site for venipuncture
Boundaries of the anatomical snuff box
Medial- tendon of the extensor pollicis longus
Lateral- tendon of the extensor pollicis brevis and abductor pollicis longus
Contents of the anatomical snuff box
Radial artery- radial pulse can be felt here Scaphoid bone (forms the floor)
Hypothenar muscles
Abductor digiti minimi
Flexor digiti minimi
Opponens digiti minimi
*innervated by the deep branch of the ulnar n
Thenar muscles
Abductor pollicis *although this intrinsic hand muscle acts on the thumb, it is innervated by the ulnar n. All the rest are innervated by the median nerve.
Abductor pollicis brevis
Flexor pollicis brevis
Opponens pollicis
Palmar hand muscles
Lumbricals
Palmar and dorsal interossei (deep branch of the ulnar nerve)
The proper palmar digital arteries
Run along the sides of the fingers and are formed when each common palmar digital artery splits
The common palmar digital arteries
Come off the superficial palmar arch
The superficial palmar arch
Is a direct continuation of the ulnar artery. The ‘arch’ is formed with a superficial branch of the radial artery
The deep palmar arch
Direct continuation of the radial artery. The ‘arch’ is formed with a deep branch of the ulnar artery
