Axilla and neurovascular input to the upper arm Flashcards
What forms the anterior wall of the Axilla?
Pectoralis Major + Minor + Subclavius
What forms the posterior wall of the axilla?
Latissmus Dorsi + Teres Major + Subscapularis
What forms the medial wall of the axilla?
Thoracic wall + Serratus anterior
What forms the lateral wall of the axilla?
Intertubercular groove of humerus
What are the contents of the axilla?
- Axillary artery
- Axillary vein
- Axillary lymph nodes
- Brachial plexus
- Biceps Brachi (short head) and coracobrachialis
At what anatomical point does the axillary artery begin?
Lateral margin of 1st rib
At what anatomical point does the brachial artery begin?
Lower margin of teres major
What nerve roots constitute the Brachial plexus?
C5-T1
What nerve roots form the upper trunk of the brachial plexus?
C5-6
What nerve roots form the middle trunk of the brachial plexus?
C7
What nerve roots form the lower trunk of the brachial plexus?
C8-T1
What is Erb’s point?
- Erb’s point is the convergance of C5+C6 when they form the upper trunk
- If damaged this can cause Erb’s palsy
What is Erb’s palsy?
- Injury to the upper trunk of brachial plexus
- Results in “waiters tip” of upper limb
- Arm is medially rotated, wrist flexed
What muscles are affected in Erb’s palsy
- Deltoid
- Wrist extensors
- Elbow flexors
What can cause Erb’s palsy?
- Hyperextension of head form shoulder
- I.e Fall on shoulder, birth injury or iatrogenic
What is Klumpke’s palsy?
- Injry to the lower trunk of the brachial plexus
- Affects intrinisc muscles of hand and ulnar flexors of wrist and fingers
What causes klumpkes palsy?
Hyper abduction of the arm
What are the cords of the brachial plexus?
Lateral Medial Posterior
What are the branches of the lateral cord of the brachial plexus?
- Lateral pectoral nerve
- Median nerve (lateral root)
- Musculocutaneous nerve
What are the branches of the medial cord of the brachial plexus?
- Medial pectoral nerve (C8-T1)
- Medial cutaneous nerve of arm (T1)
- Medial cutaneous nerve of forearm (C8-T1)
- Ulnar nerve
What are the branches of the posterior cord of the brachial plexus?
- Thoracodorsal
- Axillary nerve
- Radial nerve
- Subscapular nerve
What does the lateral pectoral nerve supply?
Pectoralis major
What does the medial pectoral nerve supply?
Pectoralis muscles
What does the thoracodorsal nerve suply?
Latissimus dorsi
What does the subscapular nerve supply?
Teres major + Supsacpularis
What is the sensory value + nerve of the badge area?
Axillary nerve - C5/6
What are the different axillary lymph nodes?
- Pectoral group
- Subscapular group
- Apical group
- Central group
- Lateral group
