Brachial Plexus Flashcards
What is the brachial plexus?
Network of nerve fibres that supplies skin and musculature of upper limb
What does the brachial plexus pass through?
Neck
Axilla
What forms the brachial plexus?
Anterior rami
of C5, C6, C7, C8, T1
What can the brachial plexus be divided into?
Roots Trunks Divisions Cords Branches
What are the roots of the brachial plexus?
C5, C6, C7, C8, T1
What do the nerve roots of the brachial plexus pass through?
Anterior and medial scalene muscles
What are the trunks of the brachial plexus?
Superior
Middle
Inferior
Where are the trunks formed?
Base of neck
What is the superior trunk made up of?
C5 and C6
What is the middle trunk made up of?
C7
What is the inferior trunk made up of?
C8 and T1
What are the divisions of the brachial plexis?
Each trunk divides into an
anterior division
and a posterior division
Where are the divisions formed?
Posterior triangle of neck
What are the cords of the brachial plexus?
Medial cord
Lateral cord
Posterior cord
Where are the cords formed?
Axilla region
The cords are named according to their…?
Relative position to the axillary artery
What is the medial cord made up of?
Anterior division of inferior trunk
What is the lateral cord made up of?
Anterior division of superior trunk
Anterior division of middle trunk
What is the posterior cord made up of?
Posterior divisions of all three trunks
What does the medial cord divide into?
Ulnar nerve
Half of the median nerve
What does the lateral cord divide into?
Musculocutaneous nerve
Half of the median nerve
What does the posterior cord divide into?
Axillary nerve
Radial nerve
What forms the ulnar nerve?
Half of the medial cord
What forms the musculocutaneous nerve?
Half of the lateral cord
What forms the median nerve?
Half of the medial cord
Half of the lateral cord
What forms the axillary nerve?
Half of the posterior cord
What forms the radial nerve?
Half of the posterior cord
What are the roots of the ulnar nerve?
C8, T1
What are the roots of the musculocutaneous nerve?
C5, C6, C7
What are the roots of the median nerve?
C6, C7, C8, T1
What are the roots of the axillary nerve?
C5, C6
What are the roots of the radial nerve?
C5, C6, C7, C8, T1
Where do the branches continue?
Into the upper limb
Which nerves branches off the roots of the brachial plexus? Which roots?
Dorsal scapular nerve - C5
Long thoracic nerve - C5, C6, C7
What nerves branch off the medial cord? What are their nerve roots?
Medial pectoral nerve
Medial cutaneous nerve of arm
Medial cutaneous nerve of forearm
C8, T1
What nerves branch off the lateral cord of the brachial plexus? What are their nerve roots?
Lateral pectoral nerve - C5, C6, C7
What nerves branch off the posterior cord of the brachial plexus?
Upper subscapular nerve - C5 C6?
Thoracodrosal nerve - C6, C7, C8
Lower subscapular nerve - C5 C6?
What nerves branch off the superior trunk? What are their nerve roots?
Suprascapular nerve - posteriorly
Subclavian nerve - anteriorly
C5, C6
