Brachial Plexus Nerve Roots And The Muscles They Innervate

Front 1

The Dorsal Scapular Nerve Root is

Back 1

c5

Front 2

The Dorsal Scapular Nerve Innervates what muscles?

Back 2

Rhomboid and Levator Scapulae

Front 3

What are the functions of the The Rhomboids and the levator scapulae?

Back 3

Rhombs- Retraction of the scapula

Levator- Elevates the scapula

Front 4

The Long Thoracic Nerve Innervates which muscles

Back 4

Serratus anterior

Front 5

What is the nerve root(s) of the long thoracic nerve?

Back 5

C5, C6, C7

Front 6

What is the function of the serratus anterior?

Back 6

The main function of the serratus anterior is to protract the scapula. It also helps stabalize the scapula and assists in upward rotation of the scapula.

Front 7

What is the nerve root(s) of the subclavian nerve?

Back 7

C5, C6

Front 8

What muscle does the subclavian nerve innervate?

Back 8

The subclavius muscle.

Front 9

The subclavian muscle's function is..

Back 9

Depression of the shoulder, carrying it downward and forward. It draws the clavicle inferiorly as well as anteriorly. This muscle protects the underlying bracial plexus and subclavian vessels from a broken clavicle- the most frequently broken long bone.

Front 10

What is the nerve root(s) for the suprascapular nerve?

Back 10

C5 and C6

Front 11

What muscle(s) is innervated by the suprascapular nerve?

Back 11

supraspinatus and infraspinatus

Front 12

What is the funtion of the supraspinatus and infraspinatus

Back 12

Supraspinatus- ABD of the arm at the shoulder jt. It is often described as the initiator of shulder ABD b/c it is the main agonist muscle for the first 15 degrees of shoulder ABD. Beyond 15 degrees the deltoid is the main agonist for ABD.

Along with other rotator cuff muscles it helps resist gravity.

It also helps to stabalize the shoulder joint by keeping the head of the humerus firmly pressed medially against the glenoid fossa of the scapula.

Infraspinatus-
It is the lateral (external rotator) of the glenohumeral joint and ABD of the arm.

The infraspinatus and the teres minor rotate the head of the humerus outward (ext rot) they also assist in extention of the arm.

Front 13

What are the nerve roots for the lateral pectoral nerve?

Back 13

C5, C6, and C7

Front 14

What are the muscles innervated by the lateral pectoral nerve?

Back 14

Pec major and minor (by communicating with the medial pectoral nerve)

Front 15

The nerve roots for the musculocutaneous nerve are?

Back 15

c5, c6, c7

Front 16

Muscles innervated by the musculocutaneous nerve are?

Back 16

coracobracialis, bracialis, and biceps brachii

Front 17

what are the fuctions of coracobracialis, bracialis, and biceps brachii?

Back 17

Coroco- shoulder flexion and and ADD

Brachialis- The brachialis is the strongest flexor of the elbow. Unlike the biceps, the brachialis does not insert on the radius, and therefore cannot participate in pronation/supination of the forearem.

Biceps brachii-
This muscles works across three joints.

It helps to flex the arm, flex the elbow joint, aids in supination of the forearm

Front 18

Lateral root of the median nerve

Nerve roots?

Back 18

c5, c6, c7

Front 19

What are the nerve roots for the subscapular nerve and what is the muscle innervated by it?

Back 19

c5, c6
upper part of the subscapularis

Front 20

What is the function of the subscapularis?

Back 20

Internal rotation
When the arm is raised, it draws the humerus forward and downward. It helps stabalize the humerus from being subluxed.

Front 21

What is the nerve roots for the the thoracodorsal nerve and what is the muscle it innervates?

Back 21

c6, c7, c8
lat. Dorsi

Front 22

What is the funtion of the lat. dorsi?

Back 22

ADD, IR and EXT of the shoulder. Depresses the scapula

Front 23

What are the nerve roots for the lower lower subscapular nerve?

What are the muscles innervated by this nerve?

Back 23

c5, c6
lower part of the subscapularis and the teres major.

Front 24

What is the origin and action of teres major?

Back 24

Origin- Distal angle of the scapula
Insertion is the interubucular groove of the humerus.

ADD, IR, and EXT of the shoulder.

Front 25

What is the nerve root of the axillary nerve?

Back 25

c5,c6

Front 26

What muscles does the axillary nerve innervate?

Back 26

ant branch: deltoid and small area of overlying skin

posterior branch: teres minor and deltoid muscles.

Front 27

What is the origin and function of the teres minor

Back 27

origin- lateral border of the scapula
insertion- lower facet of the greater tubercle of the humerus

Action-
ER of shoulder, draws humerus towards the glenoid cavity.

Front 28

Radial nerve

Roots?

Back 28

c5, c6, c7, c8, T1

Front 29

Muscles Innervated by Radial nerve

Back 29

Triceps Brachii, anconeus, the extensors of the forearm, and brachioradialis

Front 30

Medial Pectoral nerve roots and muscles it innervates.

Back 30

C8 and T1 Pec major and pec minor

Front 31

Ulnar nerve root and muscles it innervates.

Back 31

C8, T1
Flexor Carpi Ulnaris
Medial 2 bellies of Flexor Digtorm Profundus, most of the small muscles of the hand.