Brachial plexus Flashcards
What is the order of the brachial plexus from vertebrae to the axilla?
Roots >> Trunks (3) >> Divisions >> (6) >> Cords (3)
What nerves makeup the brachial plexus?
C5, C6, C7, C8, T1
http://teachmeanatomy.info/upper-limb/nerves/brachial-plexus/#Roots
What nerves make up the upper, middle and lower trunks?
C5+C6 = upper C7 = middle C8+T1 = lower
http://teachmeanatomy.info/upper-limb/nerves/brachial-plexus/#Roots
What divisions make up the cords?
Anterior div of Upper trunk (C5+C6) + Anterior div of Middle trunk (C7) makes up the Lateral Cord
Posterior division of Upper trunk, Middle trunk, and lower trunk (C8+T1) makes up the Posterior Cord
Anterior div of Lower trunk makes up the Medial cord
http://teachmeanatomy.info/upper-limb/nerves/brachial-plexus/#Trunks
What nerve comes off the C5 root?
Which muscles are innervated by this nerve?
Dorsal scapular n.
Rhomboids and Levator Scapulae
The ___ nerve is a combination of branches from C5, C6 and C7 roots
What muscle does it innervate?
Long thoracic nerve
Serratus anterior
Name one of the 2 nerve(s) that come off the Upper Trunk
It innervates the ___ and ___ muscles of the scapula.
Suprascapular n.
Supraspinatus and Infraspinatus
The nerve to ___ comes off the Upper trunk
Subclavius m.
Which nerve(s) branches off the Lateral cord? (hint: L pect + M)
Lateral pectoral n. and Musculocutaneous n.
Name the nerves that branch off the Posterior Cord (hint: ULTRA w/ 2 subscapulars)
Upper subscapular n
Lower subscapular n
Thoracodorsal n (between Upper and Lower subscapular ns.)
Radial n
Axillary n
What nerve is the terminal branch of the posterior cord?
Radial nerve
What is the first nerve that comes off of the MediaL cord?
MediaL pectoral n
The ___ ___ n of the arm and ___ ___ n of the forearm come off the medial cord
Medial cutaneous nerve of the arm
Medial cutaneous nerve of the forearm
State the nerve that is the terminal branch of the medial cord
Ulnar n
Altogether, what are the nerves that come off the Medial cord? (hint: Ulnar takes 2 many Meds for her cut arms and pect)
Ulnar n
Medial cutaneous n of the forearm
Medial cutaneous n of the arm
Medial pectoral nerve
Which nerve gets contributions from the lateral and medial cords? (the happy median)
The median n.
The anterior division of upper trunk primarily contributes to the ___ nerve
Musculocutaneous n.
Anterior division of C7 and some C8 primarily contributes to the ___ n
Median nerve
The anterior division of T1 primarily contributes to what nerve?
Ulnar nerve
Injury to the upper brachial plexus results in ___ palsy, which results when the head is pulled away from the body and is characterized by impaired function of proximal upper limb muscles. The phenotype of this condition is ___ hand, due to loss of ___ and ___.
Erb’s palsy
Waiter’s tip hand
ABduction and Supination
http://teachmeanatomy.info/upper-limb/nerves/brachial-plexus/#Clinical_Relevance_Injury_to_the_Brachial_Plexus
Injury to what brachial plexus trunk results in Klumpke’s palsy? How would this injury occur and what is its phenotype? What action of what muscles is impaired?
Lower brachial plexus trunk
Injury results from arm being pulled away from body
Phenotype is clawed hand
Flexion of the intrinsic muscles of the hand (lumbricals) at metacarpophalangeal joints
http://teachmeanatomy.info/upper-limb/nerves/brachial-plexus/#Clinical_Relevance_Injury_to_the_Brachial_Plexus
The cords of the brachial plexus are named in relation to what structure?
Axillary art
