Brachial Plexus Flashcards
What forms the brachial plexus?
The union of the anterior rami of the last 4 cervical and first thoracic
Where does the brachial plexus originate and where does it travel?
the neck and passes laterally and inferiorly over rib 1 and enters the axilla
Where do the roots of the plexus pass through?
The gap between the anterior and middle scalene muscles
What are the three trunks of the brachial plexus and how do they form?
Superior trunk - formed by the union of C5 and C6 roots
Middle trunk formed by a continuation of C7 root
Inferior trunk formed by the union of C8 and T1 ribs
What is the order of sections in the brachial plexus?
Roots Trunks Divisions Cords Nerves
What do the anterior divisions of the trunks supply?
The anterior (flexor) compartments of the upper limb
What do the posterior divisions of the trunks supply?
Posterior compartments
What are the three cords of the brachial plexus?
Lateral cord
Medial cord
Posterior cord
What is the lateral cord?
A union of anterior divisions of upper and middle trunks
What is the medial cord?
Continuation of anterior division of inferior trunk
What is the posterior cord?
Union of all three posterior divisions
What does the suprascapular nerve innervate?
Supraspinatus and infraspinatus
What does the nerve to the subclavius muscle innervate?
Subcvlavius muscle
What does the dorsal scapular nerve innervate?
Rhomboid major and minor muscles
What does the long thoracic nerve innervate?
Serratus anterior muscle
What does the musculocutaneous nerve innervate?
The anterior compartment
Coracobrachialis
Biceps brachii
Brachialis
Where does the musculocutaneuos nerve innervate?
Lateral cutaneous nerve of foreman
What forms the M over the third part of the axillary artery?
Musculocutaneuos nerve, lateral root of the median nerve,
medial root of the median nerve and ulnar nerve
What are the 5 branches of the medial cord?
Medial pectoral nerve Medial cutaneous nerve of arm medial cutaneous nerve of forearm Ulnar nerve Median nerve
What muscle does the medial pectoral nerve innervate?
Pectoralis major and minor
What muscle does the medial cutaneous nerve of the arm innervate?
Medial 1/3 of distal arm
What muscle does the medial cutaneous nerve of the forearm innervate?
Medial surface of the forearm down the wrist
What are the five branches of the posterior cord?
Superior subscapular nerve thoracodorsal nerve inferior subscapular nerve axillary nerve radial nerve
What msucle does the superior subscapular nerve innervate?
Subscapularis muscle
