Lecture 24 - Upper Limb 3 Nerves and Vessels Flashcards
Are there any anastomoses of the arteries in the arm?
If so, where?
Yes
In the elbow and wrist
What are the arteries in the upper limb?
Axillary
Brachial
Radial
Ulnar
How may a physician test the blood pressure of the heart?
Take a reading of the pressure in he brachial artery at the height of the heart.
It will be the same
Which artery is the principal cup ply to the wrist and the hand?
Ulnar artery
Which artery is used in Coronary Artery Grafts?
The Radial artery
Which drugs are never administered at the tip of fingers?
Why?
Vasoconstrictor drugs (such as adrenaline)
The fingers are end organs.
These drugs would constrict the vessels such that the fingers would get no blood supply – vasospasm and avascular necrosis
What is the name of the arteries in the fingers?
Digital arteries
What do the digital nerves supply?
Nail beds
What has happened in Volkmann’s ischemia?
- Dislocation of the elbow in a posterior direction
(Ulna forced backwards) - Brachial artery has been torn
- No supply to radial and ulnar arteries
- Necrotic forearm
What is the spatial relationship of the nerve and artery in the hand?
How about in the digits?
Hand:
The artery is superficial to the nerve
Digits:
Nerve is superficial to the artery
The superficial veins of the upper limb are highly … Compared to the arteries
Variable
What is the nerve in the hand?
Median nerve
What is the origin of the veins in the upper limb?
The dorsal venous arch of the hand
This is a network of veins on the back of the hand
Compare the path of the Cephalic and basilic veins
Cephalic: lateral
Basilic: medial
Where is the median cubital vein?
Why is it important?
In the elbow fold
It is often used for Venipuncture
What is a feature of the deep veins of the upper limb
They exist in a Venae Comitantes relationship with the arteries
Describe the flow of lymphatics in the upper limb
Interstitial fluid drains into the lymph capillaries
Lymphatics run up the arm with the superficial veins
All lymphatics from the upper limb drains in the axillary node
From axillary node on to the venous system in neck
What are watershed areas?
Where are they?
These are areas that can flow to two different collections of lymph nodes
Cervical-axillary watershed: along chest above axilla
Inguinal-Axillary watershed: along belly button plane
What is the function of the thoracic duct?
It transports lymph from the axillary lymph nodes to the venous system in the neck
Which areas do the axillary nodes drain?
The upper limbs and the chest
What is a nerve plexus?
A collection of intersecting nerves from the spinal cord
Where do the muscles, bones and skin of the limbs get their nerve innervation?
Nerve plexuses
Which segments make up the brachial plexus?
C5 - T1
Which rami form the brachial plexuses?
The anterior rami
Which muscle compartment does the anterior division of the brachial plexus go to?
How about the posterior compartment?
Anterior: Flexor
Posterior: extensor
Which veins does the dorsal venous arch give rise to?
Cephalic vein
Basilic
Median cubital
What are the major peripheral nerves of the upper limb?
Musculocutaneous
Median
Ulnar
Axillary
Radial
Which segments supply the musculocutaneous nerve?
C5,6
What does the musculocutaneous nerve supply?
Muscle: Flexor compartment (biceps, brachialis, coracobrachialis)
Skin:
Lateral aspect of forearm
Which segments supply the median nerve?
C5-T1
What does the median nerve supply?
Muscles
Most muscles of anterior compartment of forearm
Skin:
Anterior aspects of lateral 3 and half digits + nail beds
What is the median nerve susceptible to?
Carpal tunnel syndrome
- compression injury
Which segments supply the ulnar nerve?
C8 and T1
What does the ulnar nerve supply?
Muscle:
Remaining muscles in anterior compartment of the hand
Skin:
Medial 1 and half digits
(Palmar and dorsal)
What is the ulnar nerve susceptible to?
Stretch along medial epichondyle
–> hitting funny bone
Compression when leaning on bike handles (for example)
Does the ulnar nerve pass through the flexor retinaculum?
No, unlike the median nerve, it passes superficial to the flexor retinaculum
Which segments supply the axillary nerve?
C5,6
What does the axillary nerve supply?
Muscle:
Deltoids
Skin:
Skin over shoulder
What is the axillary nerve susceptible to?
Injury during shoulder dislocation
Fracture of surgical neck of the humerus
Which segments supply the radial nerve?
C5-T1
What does the radial nerve supply?
Muscles:
Extensor muscles of arm and forearm (posterior compartment)
Skin:
Arm
Forearm
Back of hand
What is the radial nerve susceptible to?
Humoral shaft fraction
Compression (Saturday night palsy)
Which nerve supplies the thumb?
Median nerve
Which nerve supplies the back of the hand?
Radial nerve
+ ulnar nerve (medial 1 1/2 fingers)
What is Erb’s palsy?
Waiter’s tip position
(shoulder flexed, elbow extended, forearm pronated)
Due to forceful lateral flexion of the head on shoulder
Damage to C5,6
What nerves are commonly damaged in injury to the upper trunk?
What about the lower trunk?
Upper trunk: C5,6
Lower trunk: C8, T1
What is Klumpke’s palsy?
Injury to the lower trunk
Flexion of wrist and fingers (claw like hand)
