upper arm - insertion, action, innervation

Question 1

trapezius - proximal origin

Answer 1

• occipital bone
• ligaments nuchae
• C7, T1-12

Question 2

trapezius - distal insertion

Answer 2

• clavicle
• acromion
• scapular spine

Question 3

trapezius - action

Answer 3

Superior fibres:
Elevation

Middle fibres:
Retraction

Inferior fibres:
Depression

> of scapula

Question 4

trapezius - innervation

Answer 4

motor: CN XI (accessory)
proprioceptive: C3, C4

Question 5

Latissimus dorsi - proximal origin

Answer 5

• aponeurosis of posterior layer of thoracolumbar fascia (attaches to all lumbar and sacral vertebrae)
• spinous processes of T7-T12
• posterior iliac crest
• fleshy digitations of caudal-most 4 ribs

Question 6

Latissimus dorsi - distal insertion

Answer 6

curves around lower border of teres major to insert into intertubercular groove of humerus as a tendon

Question 7

Latissimus dorsi - action

Answer 7

extends, adducts, medially rotates humerus

(Raises body towards arms e.g. climbing, chin-ups)

Question 8

Latissimus dorsi - innervation

Answer 8

Thoracodorsal nerve (C6-C8)

(C6, C7 mainly)

Question 9

Levator scapulae - proximal origin

Answer 9

transverse processes of C1-C4

Question 10

Levator scapulae - distal insertion

Answer 10

superior portion of the medial border of the scapula from its superior angle to its spine

Question 11

Levator scapulae - action

Answer 11

• Together with trapezius levator scapulae works to elevate, retract and stabilize the scapula.
• Also when working with trapezius, bilateral contraction produces extension of the neck, while one side produces lateral flexion of the neck.
• It is also active in resisted medial rotation of the scapula.

Question 12

Levator scapulae - innervation

Answer 12

• direct branches from C3 and C4
• and a branch from dorsal scapular nerve (C5)

Question 13

deltoid - proximal origin

Answer 13

• anterior border of lateral third of clavicle
• superior surface of acromion
• spine of scapula

Question 14

deltoid - distal insertion

Answer 14

fibres convene into a tendon inserting laterally into deltoid tuberosity

Question 15

deltoid - action

Answer 15

Anterior fibres: flexion and medial rotation

Middle fibres: abduction

Posterior fibres: extension and lateral rotation

> of shoulder

Question 16

deltoid - innervation

Answer 16

axillary nerve (C5, C6)

Question 17

supraspinatus and infraspinatus - proximal origin

Answer 17

supraspinatus and infraspinatus fascia and fossa

Question 18

supraspinatus and infraspinatus - distal insertion

Answer 18

supra: The tendon inserts on the upper facet of greater tuberosity of the humerus
infra: The tendon inserts on the middle facet of the greater tuberosity of the humerus.

Question 19

supraspinatus and infraspinatus - action

Answer 19

supra: initiates abduction, and as part of the rotator cuff, helps to hold the humeral head in the socket throughout its range of movement
infra: lateral rotation of the humerus, but its more important action is as a member of the rotator cuff

Question 20

supraspinatus and infraspinatus - innervation

Answer 20

supra: Suprascapular nerve (C4, C5, C6)
infra: Suprascapular nerve (C5, C6)

Question 21

teres major and minor - proximal origin

Answer 21

minor: lateral border of scapula
major: dorsal surface of inferior angle of scapula

Question 22

teres major and minor - distal insertion

Answer 22

minor: inferior facet on greater tubercle of humerus
major: medial lip of inter tubercular groove of humerus

Question 23

teres major and minor - action

Answer 23

minor: adduction and lateral rotation of the humerus
- and helps to oppose upward subluxation of the humerus due to the powerful actions of deltoid, biceps brachii, and triceps. Its main action is as a member of the rotator cuff.
major: extends the shoulder, adducts and medially rotates the humerus.

Question 24

teres major and minor - innervation

Answer 24

minor: Axillary nerve (C5,6)
major: Lower subscapular nerve (C5, C6)

Question 25

subscapularis - proximal origin

Answer 25

medial two thirds of the costal surface of the scapula, separated from the neck of scapula by subscapularis bursa

Question 26

subscapularis - distal insertion

Answer 26

inserts on the lesser tuberosity, shoulder joint capsule, and the front of the upper shaft of the humerus

Question 27

subscapularis - action

Answer 27

adductor and medial rotator of the humerus

Question 28

subscapularis - innervation

Answer 28

both subscapular nerves (C5,**C6**,C7)

Question 29

pectoralis major - proximal origin

Answer 29

- sternal half of clavicle - upper half of sternum - aponeurosis of external abdominal oblique

Question 30

pectoralis major - distal insertion

Answer 30

converge towards anterior wall of axilla. all 3 parts of the muscle (clavicular, sternal, abdominal) end as a flat tendon inserting into intertubercular groove of humerus

Question 31

pectoralis major - action

Answer 31

- primarily adduction of arm at shoulder - also medially rotates the humerus and clavicular portion will help flex shoulder and adduct humerus medially - sternocostal portion, along with latissimus dorsi and teres major can extend flexed humerus to side of trunk against resistance.

Question 32

pectoralis major - innervation

Answer 32

medial and lateral pectoral nerves (C5-C8 and T1)

Question 33

biceps brachii - proximal origin

Answer 33

short head - apex of coracoid process of scapula long head - supraglenoid tubercle of scapula

Question 34

biceps brachii - distal insertion

Answer 34

radial tuberosity tendon also gives off a broad aponeurosis medially which fuses with deep fascia of forearm

Question 35

biceps brachii - action

Answer 35

- powerful **supinator** - flexor of the elbow, particularly if the forearm is supinated - acts to some extent as a flexor of the shoulder

Question 36

biceps brachii - innervation

Answer 36

C5, **C6**

Question 37

coracobrachialis - proximal origin

Answer 37

originates from the tip of the coracoid process, medial to the short head of biceps

Question 38

coracobrachialis - distal insertion

Answer 38

medial aspect of the mid shaft of the humerus

Question 39

coracobrachialis - action

Answer 39

Flexes the arm forwards adduction

Question 40

coracobrachialis - innervation

Answer 40

Musculocutaneous nerve (C5,**C6,C7)**

Question 41

Brachialis - proximal origin

Answer 41

distal half of anterior humerus

Question 42

Brachialis - distal insertion

Answer 42

tuberosity and anterior surface of coronoid process of ulna

Question 43

Brachialis - action

Answer 43

powerful flexor of forearm at the elbow

Question 44

Brachialis - innervation

Answer 44

Musculocutaneous nerve (C5, **C6**)

Question 45

triceps brachii - proximal origin

Answer 45

Long head: Infraglenoid tubercle of scapula Lateral head: post. humerus, sup. to radial groove Medial head: post. humerus, inf. to radial groove

Question 46

triceps brachii - distal insertion

Answer 46

olecranon process of ulna

Question 47

triceps brachii - action

Answer 47

Extension of the elbow joint

Question 48

triceps brachii - innervation

Answer 48

Radial Nerve (C6, **C7, C8**)

Question 49

Anconeus - proximal origin

Answer 49

Lateral epicondyle of humerus

Question 50

Anconeus - distal insertion

Answer 50

lateral olecranon and superior posterior surface of ulna

Question 51

Anconeus - action

Answer 51

- Assists in extension of elbow joint - Abducts ulna during pronation - WRIST DROP characteristic of radial nerve injury

Question 52

Anconeus - innervation

Answer 52

Radial Nerve (C7, C8, T1)

Question 53

Pectoralis minor - proximal origin

Answer 53

ribs 3-5

Question 54

Pectoralis minor - distal insertion

Answer 54

coracoid process

Question 55

Pectoralis minor - action

Answer 55

- protraction - medial roatation \>of scapula

Question 56

Pectoralis minor - innervation

Answer 56

medial pectoral nerve (C8, T1)

Question 57

serratus anterior - proximal origin

Answer 57

ribs 1-8

Question 58

serratus anterior - distal insertion

Answer 58

medial border of scapula

Question 59

serratus anterior - action

Answer 59

- protraction - depression - lateral roatation \>of scapula

Question 60

serratus anterior - innervation

Answer 60

long thoracic nerve (C5, **C6, C7**)

Question 61

Rhomboid major and minor - proximal origin

Answer 61

Minor: nuchal ligament, spinous processes C7-T1 Major: spinous processes T2-T5

Question 62

Rhomboid major and minor - distal insertion

Answer 62

Minor: medial end of scapular spine Major: medial border of scapula

Question 63

Rhomboid major and minor - action

Answer 63

- retraction - medial rotation \>of scapula

Question 64

Rhomboid major and minor - innervation

Answer 64

Dorsal scapular (C5) and cervical (C3, C4) nerves