Axilla, brachial plexus & muscles of anterior arm Flashcards
What structures form the anterior wall of the axilla?
Pec major
Pec minor
What structures for the posterior wall of the axilla?
Subscapularis
Teres minor
Latissimus dorsi
What structures form the lateral wall of the axilla?
Upper end of the humerus
Bicep brachii
Coracobrachialis
What structures form the medial wall of the axilla?
Serattus anterior covering the ribs
Intercostal spaces
What structures in front form the apex of the axilla?
1st rib medially with the clavicle
What structure behind form the apex of the axilla?
Scapula
What does the apex of the axilla act as between the trinangle of the neck and the axilla?
channel of communication
What forms the base of the axilla?
skin and fascia extending between the chest wall and arm
What does the axilla contain?
Fat and lymph nodes
Axillary artery which supplies the upper limb
Axillary vein- venous drainage of the arm
Brachial plexus- nerve supplying the arm
What structures do the lymph nodes in the axilla drain?
Upper limbs Chest wall (front and back) Abdominal wall as far as umbilicus
Why are the lymph nodes of the axilla clinically important?
Commonly involved with cancerous spread, particularly from the breast.
What are the roots of the brachial plexus?
C5-T1
What is the nerve supply for the full posterior arm?
Radial
What is the nerve supply for the anterior upper arm?
Musculocutaneous
What is the nerve supply for the anterior fore arm?
Median
What is the nerve supply for the hand (minus the thumb)
Ulna
What is the nerve supply for the thumb region of the hand?
Median
What roots of the brachial plexus are damaged in an Erbs palsy?
Upper one or two roots
What muscles are paralysed in Erbs palsy?
Extensor muscles of the wrist
What clinical observation would paralysis of the extensor muscles of the wrist show?
‘Waiters tip’
What roots of the brachial plexus are damaged in a Klumpkes palsy?
Lower one or two roots of the brachial plexus
What is left paralysed in a Klumpkes palsy?
Muscles in the hand are paralysed
What nerve roots form the lower root of the brachial plexus?
T1 nerve root
What nerve root of the brachial plexus carries supply to the face?
T1 nerve root
What will damage to the T1 nerve root cause?
drooping eyelid
anhidrosis- lack of sweating on the face
miosis- constricted pupils
What is the name of the syndrome that develops as a result of damage to the T1 nerve root?
Horners syndrome
