Brachial Plexus

Which nerves are involved in the brachial plexus?

Spinal nerves C5 - T1

What nerves make up the superior trunk of the brachial plexus?

C5 and C6

What are the pre-plexus nerves discussed? (names only)

Dorsoscapular, Long Thoracic

Which nerve does the dorsoscapular nerve originate from?

the C5 spinal nerve

What does the dorsoscapular nerve innervate?

Rhomboid Major and Minor, and Levator Scapulae muscles

What two nerves branch off of the Superior trunk of the brachial plexus? (names only)

Suprascapular and Subclavius Nerves

Which spinal nerve is the main contributing nerve to the suprascapular nerve?

C5*, C6

Which spinal nerve is the main contributing nerve to the Subclavius nerve?

C4, C5, C6*

What muscle(s) and/or joints do(es) the suprascapular nerve innervate?

Supraspinatus, Infraspinatus, Glenohumeral joint

What muscles(s) and/or joints do(es) the subclavius nerve innervate?

Subclavius muscle, sternoclavicular joint

What spinal nerves contribute to the Long Thoracic Nerve?

C 5, C6, and C7

What muscle(s) do(es) the Long Thoracic nerve innervate?

Serratus Anterior muscle

What divisions contribute to the Lateral Cord of the brachial plexus?

The anterior division of the Middle Trunk and the continuation of the Superior Trunk

What nerve branches off from the Lateral Cord of the brachial plexus? (name only)

Lateral Pectoral Nerve

What muscle(s) do(es) the lateral pectoral nerve innervate?

Pectoralis major muscle (some minor)

Which spinal nerves contribute to the lateral pectoral nerve?

C5, C6*, C7

Which spinal nerves contribute to the Musculocutaneous nerve?

C5, C6, C7

Which cord(s) contribute to the musculocutaneous nerve?

the Lateral Cord

Which trunk(s) contribute to the musculocutaneous nerve?

the Superior Trunk and the anterior division of the Middle Trunk

What muscle(s) and/or joint(s) does the Musculocutaneous nerve innervate?

ANTERIOR ARM: brachialis, biceps brachii, coracobrachialis

What area of the skin does the musculocutaneous nerve contribute to?

Radial Forearm Skin

What branch(es) come(s) off from the Posterior Cord of the brachial plexus? (names only)

Upper subscapular, Thoracodorsal, Lower subscapular nerves.

What does the Posterior Cord turn into? (names only)

the Radial Nerve and the Axillary Nerve

What muscle does the upper subscapular nerve innervate?

Superior subscapularis muscle

What muscle does the Thoracodorsal nerve innervate?

Latissimus Dorsi muscle

What spinal nerves contribute to the upper subscapular nerve?

C5*, C6

What spinal nerves contribute to the thoracodorsal nerve?

C6, C7*, C8

What spinal nerves contribute to the lower subscapular nerve?

C5, C6*, C7

What trunks make up the posterior chord of the brachial plexus?

the posterior division of the superior trunk and the posterior division of the inferior trunk

What muscle does the lower subscapular nerve innervate?

Inferior subscapularis muscle and teres major muscle

What muscle(s) and/or joint(s) do(es) the Axillary nerve innervate?

Teres Minor muscle, Deltoid muscle, Glenohumeral Joint

What skin does the sensory portion of the axillary nerve innervate?

The lateral arm skin, skin over the deltoid

What spinal nerves contribute to the axillary nerve?

C5, C6

What spinal neves contribute to the radial nerve?

C5 - T1

What muscle(s) and/or joint(s) do(es) the Radial nerve innervate?

ALL DORSAL FOREARM MUSCLES. Brachioradialis, Extensor carpi radialis longis, Extensor carpi radialis brevis, Extensor digitorum, Extensor carpi ulnaris, Supinator, Extensor pollicis longis, Extensor indices, Extensor digiti minimi, Abductor Pollicis longis, Pronator Quadratus

What portion of the skin is specific to the sensory innervation by the radial nerve?

The web between the thumb and the index finger, dorsally

What spinal nerves contribute to the median nerve?

C6, C7, C8, T1

What muscle(s) and/or joint(s) do(es) the median nerve innervate?

THENAR group: Flexor Pollicus Brevis, Abductor Pollicus Brevis, Opponens Pollicus; Anterior Forearm: Pronator Teres, Flexor Carpi Radialis, Palmaris Longis, NOT Flexor Carpi Ulnaris, NOT 1/2 of flexor digitorum profundus, 1/2 of lumbricals

What portion of the skin does the sensory portion of the median nerve innervate?

Palmar Skin, from the thumb to the lateral 1/2 of the ring finger.

What cords contribute to the median nerve?

Lateral Cord and the Medial Cord

What trunks contribute to the median nerve?

Superior, Middle and Inferior Trunks

What cord(s) contributes to the radial nerve?

The Posterior Cord

What cord(s) contribues to the axillary nerve?

The Posterior Cord

What trunk(s) contribute to the radial nerve?

Superior trunk, Middle Trunk, Inferior Trunk

What trunk(s) contribute to the axillary nerve?

The Superior trunk

What nerves branch off of the inferior trunk of the brachial plexus?

none

What nerves branch off of the medial cord of the brachial plexus? (names only)

Medial Pectoral, Medial Brachial Cutaneous, and Medial Antebrachial Cutaneous nerves

What muscle does the medial pectoral nerve innervate? (name only)

Pectoralis Minor muscle, some of pectoralis major

What spinal nerves contribute to the medial pectoral nerve?

C8, T1

What spinal nerves contribute to the medial brachial cutaneous nerve?

C8, T1

What does the medial brachial cutaneous nerve innervate?

The skin on the medial arm

What does the medial antebrachial cutaneous nerve innervate?

The skin on the medial forearm

What spinal nerves contribute to the Ulnar nerve?

C8, T1 (sometimes C7)

What cord(s) contribute to the Ulnar nerve?

The medial cord

What divisions contribute to the posterior cord?

All 3 posterior divisions of the trunks

What muscle(s) and/or joint(s) do(es) the ulnar nerve innervate?

HYPOTHENAR group: abductor digiti minimi, flexor digiti minimi, opponens digiti minimi; the flexor carpi ulnaris, 1/2 of the flexor digitorum profundus, the interosseus muscles (dorsal and palmar), 1/2 of lumbricals

What area of the skin does the sensory portion of the ulnar nerve innervate?

the skin on the medial hand