Brachial Plexus and Nerves of the Upper Limb Flashcards
What is the origin of the dorsal scapular nerve?
Posterior aspect of anterior ramus of C5 with frequent contribution from C4
What nerves make up the supraclavicular branch of the brachial plexus?
Dorsal scapular, long thoracic, suprascapular, and subclavian
What structures does the dorsal scapular nerve innervate?
Rhomboids and sometimes levator scapulae
What is the origin of the long thoracic nerve?
Posterior aspect of anterior rami of C5, C6, C7
What structures are innervated by the long thoracic nerve?
Serratus anterior
What is the origin of the suprascapular nerve?
Superior trunk receiving fibers from C5, C6 and oftern C4
What structures are innervated by the suprascapular nerve?
The supraspinates and infraspinatus; essentially the glenohumeral joint
What is the origin of the subclavian nerve?
Superior trunk receiving fibers from C5, C6, and often C4
What is the origin of the lateral pectoral nerve?
Side branch of lateral cord, receiving fibers from C5, C6, C7
What structures are innervated by the lateral pectoral nerve?
Primarliy pectoralis major but some nevre fibers pass to pectoralis minor via medial pectoral nerve
What is the origin of the musculocutaneous nerve?
Terminal branch of lateral cord, receiving fibers from C5-C7
What structures are innervated by the musculocutaneous nerve?
Muscles of the anterior compartment of the arm (coracobrachialis, biceps brachii, and brachialis) and skin of lateral aspect of forearm
What is the origin of the median nerve?
Lateral root of median nerve is a terminal branch of lateral cord (C6, C7)
Medial root of median nerve is a terminal branch of medial cord (C8, T1 fibers)
What structures are innervated by the median nerve?
Muscles of the anterior forearm compartment (except for flexor carpi ulnaris and ulnar half of flexor digitorum profundus), five intrinsic muscles in the ulnar half of palm and palmar skin
What is the origin of the medial pectoral nerve?
Side branches of medial cord, receiving fibers from C8, T1
What structures are innervated by medial pectoral nerve?
Pectoralis minor and sternocostal part of pectoralis major
What is the origin of the medial cutaneous nerve of arm?
Side branches of medial cord, receiving fibers from C8, T1
What structures are innervated by the medial cutaneous nerve of arm?
Skin of medial side of arm, as far distal as medial epicondyle of humerus and olecranon of ulna
What is the origin of the median cutaneous nerve of forearm?
Side branches of medial cord, receiving fibers from C8, T1
What structures are innervated by median cutaneous nerve of forearm?
Skin of medial side of forearm, as far distal as wrist
What is the origin of the ulnar nerve?
Larger terminal branch of medial cord, receiving fibers from C8, T1, and often C7
What structures are innervated by the ulnar nerve?
Flexor carpi ulnaris and ulnar half of flexor digitorum profundus (forearm), most intrinsic muscles of hand, and skin of hand medial to axial line of digit 4
What is the origin of the upper subscapular nerve?
Side branches of posterior cord, receiving fibers from C5
What structures are innervated by upper subscapular nerve?
Superior portion of subscapularis
What is the origin of the lower subscapular nerve?
Side branch of posterior cord, receiving fibers from C6
What structures are innervated by lower subscapular nerve?
Inferior portion of subscapularis and teres major
What is the origin of the thoracodorsal nerve?
Side branch of posterior cord, receiving fibers from C6, C7, C8
What structures are innervated by the thoracodorsal nerve?
Latissimus dorsi
What is the origin of the axillary nerve?
Terminal branch of posterior cord, receiving fibers from C5, C6
What structures are innervated by the axillary nerve?
Glenohumeral joint, teres minor, and deltoid muscles, also skin of superolateral arm over inferior part of deltoid
What is the origin of the radial nerve?
Larger terminal branch of posterior cord (largest branch of plexus), receiving fibers from C5-T1
What structures are innervated by the radial nerve?
All muscles of posterior compartments of arm and forearm, skin of posterior and inferolateral arm, posterior forearm, and dorsum of hand lateral to axial line of digiti 4
What is the origin of the anterior interosseous nerve?
Median nerve in distal part of cubital fossa
What is the origin of the palmar cutaneous branch of median nerve?
Median nerve of middle to distal forearm, proximal to flexor retinaculum
What is the origin of the palmar cutaneous branch of ulnar nerve?
Ulnar nerve near middle forearm
What is the origin of the dorsal cutaneous branch of ulnar nerve?
Ulnar nerve in distal half of forearm
What is the origin of the posterior cutaneous nerve of forearm?
Radial nerve, as it traverses radial groove of posterior humerus
What is the origin of the superficial branch of radial nerve?
Sensory terminal branch of radial nerve, in cubital fossa
What is the origin of the deep branch of radial nerve/posterior interosseous nerve?
Motor terminal branch of radial nerve, in cubital fossa
What is the origin of the lateral cutaneous nerve of forearm?
Continuation of musculocutaneous nerve distal to muscular branches
What is the origin of the medial cutaneous nerve of forearm?
Medial cord of brachial plexus, receiving C8 and T1 fibers
