UL2 - Neurovasculature to forearm, wrist & elbow Flashcards
what veins do the deep veins drain into before joining with the basilic/axillary vein?
brachial vein - paired veins that surround the brachial artery
through which anatomical structure does the cephalic vein pass before draining into WHAT vein?
axillary vein - passes through the deltopectoral groove before draining into the axillary vein within the clavipectoral triangle/fascia
describe the origin and course of the basilic vein & what vein it drains into
originates from the dorsal venous arch
ascends the medial aspect of the UL as a superficial vein
drains into the axillary vein
what vein does the axillary vein drain into?
subclavian vein - which drains into superior vena cava
describe the origin and course of the cephalic vein & what vein it drains into
originates from the lateral side of the dorsal venous arch of the hand
ascends the lateral aspect of the UL as a superficial vein
travels through the deltopectoral groove (between the deltoid & pectoralis major) - drains into the axillary vein at the clavipectoral triangle
what vein bridges the basilic & cephalic veins at the level of the cubital fossa?
median cubital vein
what arteries do the deep veins of the upper limb follow? what do they drain into?
the radial and ulnar arteries - drain into the paired brachial veins
how do the brachial veins contribute to venous drainage in the upper limb?
paired veins that surround the brachial artery - drain into the basilic or axillary artery
what veins arise from the dorsal venous arch of the hand?
palmar and metacarpal venous tributaries
at which anatomical point does the brachial artery bifurcate? what are the two branches it forms?
at the level of the neck of the radius - bifurcates into the radial & ulnar arteries
what branch does the ulnar artery give off, and into which arteries does it divide
common interosseus artery - divides into the anterior & posterior interosseus arteries (relative to the interosseus membrane)
to what muscles does the ulnar artery run DEEP to? what arterial arch does it form?
along the medial forearm, DEEP to flexor carpi ulnaris & flexor digitorum profundus
forms the superficial palmar arch –> common and proper palmar digital arteries
through which anatomical structure does the ulnar artery pass to enter the hand?
superficial to flexor retinaculum through Guyon’s canal
what is the course of the radial artery in the forearm and hand?
- bifurcation from the brachial artery at the level of the radial neck
- superficial to the radius, deep to the brachioradialis
- passes laterally at the wrist (pulse point)
- wraps around to pass through the anatomical snuff box
- forms the deep palmar arch
what palmar arch does the radial artery form?
deep palmar arch
what is the clinical significance of the anastomosis between the superficial and deep palmar arches?
collateral blood flow between the ulnar & radial arteries - assessed during Allen’s test to ensure a complete palmar arch
what arteries supply the fingers? how are they derived?
proper palmar digital arteries - derived from common palmar digital arteries of the superficial & palmar metacarpal arteries from the deep palmar arches anastomosing
where is the radial pulse detected relative to the flexor carpi radialis?
lateral to the flexor carpi radialis tendon at the wrist
what artery runs deep to the pronator teres?
ulnar artery
what two muscles does the ulnar artery run deep to in the forearm?
flexor carpi ulnaris
flexor digitorum profundus
what do the palmar metacarpal arteries arise from? how do they contribute to arterial supply in the hand?
arise from the deep palmar arch - anastomose with common palmar digital arteries to form proper palmar digital arteries that supply the fingers
where does the radial artery go after passing the lateral aspect of the wrist?
through anatomical snuff box –> forms the deep palmar arch
what is being assessed during an Allen’s test?
collateral blood flow between the radial and ulnar arteries by checking for a complete palmar arch
nerve roots & cord origins of the radial nerve?
roots - C5-T1
cord - posterior
at what anatomical structure does the radial nerve divide into its superficial and deep branches?
level of the cubital fossa
what is the continuation of the deep branch of the radial nerve?
posterior interosseus nerve
which areas of the hand are supplied by the superficial branch of the radial nerve?
skin of the lateral 3 1/2 fingers on the hand dorsum
through which anatomical structure does the median nerve pass at the wrist?
through carpal tunnel - deep to flexor retinaculum
of what nerve is the anterior interosseus nerve a branch of? function?
the median nerve - supplies deep muscles of the anterior forearm compartment (apart from the medial half of the flexor digitorum profundus & flexor carpi ulnaris)
which muscles are innervated by the recurrent branch of the median nerve?
thenar eminence
what muscle does the deep branch of the radial nerve pierce? what does it do from here?
supinator - passes into the posterior forearm compartment & continues as the posterior interosseus nerve
how does the radial nerve pass relative to the lateral epicondyle? what does it do from here?
anterior - then divides into a superficial and deep branch at the level of the cubital fossa
describe the course of the median nerve
arises from C5/6-T1 nerve roots & medial and lateral cords
lies medial to the brachial artery at the cubital fossa & deep to the bicipital aponeurosis - runs deep to the pronator teres between the two heads
gives off anterior interosseus branch - supplies most of the anterior forearm compartment muscles
continues in between flexor digitorum profundus and superficialis - passes deep to flexor retinaculum through carpal tunnel and gives off recurrent branch of the median nerve - supplies thenar eminence
continues as common palmar digital nerves - then as proper palmar digital arteries = supplies lateral 3 1/2 fingers & loops over to hand dorsum to supply areas the radial nerve doesn’t
muscle tendons contained in the carpal tunnel?
flexor pollicis longus
flexor digitorum profundus
flexor digitorum superficialis
nerve at risk of compression in the carpal tunnel?
median nerve
floor/walls & roof of carpal tunnel?
floor & walls - carpal bones
roof - flexor retinaculum (tough fibrous ligament that spans the carpal arch)
describe the course of the ulnar nerve
arises from C8-T roots & medial cord
passes posterior to the medial epicondyle & in between the heads of the flexor carpi ulnaris
goes in between the flexor carpi ulnaris and flexor digitorum profundus - branches supply medial 1/2 of FDP
continues down medial forearm, superior to flexor retinaculum - gives off superficial and deep branches
superficial branch continues as common & proper palmar digital nerves
deep branch supplies intrinsic hand muscles (not thenar eminence & 1st or 2nd lumbricals)
where does the ulnar nerve pass at the elbow? what clinical condition can arise here?
passes POSTERIOR to medial epicondyle & between two heads of the flexor carpi ulnaris - before passing deep to FCU and FDP
condition: cubital tunnel syndrome - compression of the ulnar nerve
which structures are supplied by the deep branch of the ulnar nerve in the hand?
intrinsic hand muscles - not the thenar eminence or 1st and 2nd lumbricals
what nerve pierces the supinator? what does it continue as?
radial nerve - continues as the posterior interosseus nerve
what nerve supplies the medial 1 and 1/2 fingers?
dorsal branch of the ulnar nerve
what structure is not part of the carpal tunnel but passes within its own tunnel?
tendon of flexor carpi radialis
roof, floor, medial and lateral boundaries of the cubital/ulnar tunnel?
roof - joint capsule & ulnar collateral ligament
floor - cubital tunnel retinaculum
medial wall - medial epicondyle of humerus
lateral - olecranon process of ulna
which nerve passes through the cubital tunnel?
ulnar nerve
symptoms of cubital tunnel syndrome?
numbness/weakness in medial 1 and 1/2 fingers & muscle wasting in intrinsic hand muscles supplied by the ulnar nerve
where else can the ulnar nerve be compressed apart from the cubital tunnel?
at the wrist in Guyon’s canal - often due toa ganglion cyst
what nerve passes through the carpal tunnel? what symptoms would arise if this nerve was compressed?
median nerve - compression causes carpal tunnel syndrome
sensory changes in lateral 3 1/2 fingers
thenar muscle wasting
