Lecture 6: The Axilla & Brachial Plexus Flashcards
What’s the axillas function
to act as a passageway for neurovascular structures
The Axillary Artery arises from the
subclavian artery at the first rib
The Axillary Artery gives rise to
the brachial artery at the inferior border of teres minor
The Axillary Arteries 3 distinctions
- proximal to pec minor
- deep to pec minor
- inferior to pec minor
What are the terminal branches of the brachial artery
- the radial artery
- the ulnar artery
The Axillary Vein gives rise to
the basilic vein at the inferior border of teres minor
The Axillary Vein arises from
the subclavian vein at the first rib
Cephalic Vein is
superficial
Brachial Vein is
deep
Distal to spinal sensory ganglion, dorsal & ventral roots ________
combine to form a mixed spinal nerve
The Mixed spinal nerve divides into
posterior and anterior rami
the nervous plexus’s innervating the limbs arise from
the anterior rami
The anterior and posterior rami contain
both motor and sensory neurons
Myotome definition
portion of skeletal muscle innervated by a single spinal nerve
Dermatome definition
portion of the skin innervated by a single spinal nerve
The Brachial Plexus definition
network of nerves innervating the upper limb and muscles of the thorax
What vertebrae does the brachial plexus arise from
C5 to T1
What are the 5 anatomical divisions of the brachial plexus (proximal to distal)
Read The Damn Cadaver Book
- Roots
- Trunks
- Divisions
- Cords
- Branches
The relative positions of the brachial plexus
- emerges between the anterior and middle scalane
- deep to the clavicle and pec minor
- overlying the subscapularis
Roots
C5 to T1
Cords
- Lateral
- Posterior
- Medial
Branches
- Musculocutaneous
- Axillary
- Radial
- Median
- Ulnar
The lateral and medial cord give rise to
the median branch
The posterior cord gives rise to the
axillary and radial branches
the lateral cord gives rise to
the musculocutaneous branch and the lateral root
The Axillary Nerve innvervates
- deltoids
- teres minor
The Radial nerve innervates
- posterior arm
- brachialis
- posterior forearm
The musculocutaneous nerve innervates
- coracobrachialis
- biceps
- brachialis
The median nerve innervates
- anterior forearm
- thenar muscles
the ulnar nerve innervates
- medial flexors
- intrinsic hand muscles
Root Avulsion definition
Roots pulled out of spinal cord
Root Stretch definition
distal stretch stopping the flow of information
Root Rupture definition
distal break in the plexus
Upper trunk Palsy
loss of innervation to the
- abductors
- lateral rotators
- forearm flexors
- wrist extensors
Lower Trunk Palsy
loss of innervation to the
- pronators
- intrinsic hand muscles
C5 root travels to
- musculocutaneous nerve
- axillary nerve
- median nerve
- radial nerve
C6 root travels to
- musculocutaneous nerve
- axillary nerve
- median nerve
- radial nerve
C7 root travels to
- musculocutaneous nerve
- median nerve
- radial nerve
C8 root travels to
- median nerve
- radial nerve
- ulnar nerve
T1 root travels to
- median nerve
- radial nerve
- ulnar nerve
Anterior Deltoid Function
flexes and medially rotates the arm at GHJ
Lateral Deltoid Function
abducts the arm at the GHJ
Posterior Deltoid Function
extends and laterally rotates the arm at the GHJ
