Shoulder

Question 1

Serratus Anterior

Answer 1

Origin: surface of upper 8-9 ribs

Insertion: medial border of scapula

Innervation: long thoracic nerve (C5, C6, C7)

Function: Abduction and upward rotation of the scapula; stabilizes medial border of scapula

Question 2

Rhomboid Major

Answer 2

Origin: spinous process of TII-TV vertebrae

Insertion: medial border of scapula from the spine of the scapula to the inferior angle

Innervation: dorsal scapular nerve (C4, C5)

Function: elevates and adducts the scapula

Question 3

Rhomboid Minor

Answer 3

Origin: spinous process of CVII and TI vertebrae

Insertion: medial border of scapula at the root of the spine of the scapula

Innervation: dorsal scapular nerve (C4, C5)

Function: elevates and adducts the scapula

Question 4

Lattissimus Dorsi

Answer 4

Origin:

1. Spinous processes of T7-T12 vertebrae
2. Thoracolumbar fascia to the spinous process of the lumbar vertebrae
3. Related interspinous ligaments and iliac crest; lower 3-4 ribs

Insertion: floor of intertubercular sulcus of humerus

Innervation: Thoracodorsal nerve (C6, C7, C8)

Function: adduction, medial rotation, and extension of the shoulder (humerus)

Question 5

Deltoid

Answer 5

Origin: lateral 1/3 of clavicle, acromion, and scapular spine

Insertion: deltoid tuberosity of humerus

Innervation: axillary nerve (C5, C6)

Function: both: shoulder abduction
Anterior: Shoulder flexion and internal rotation
Posterior: shoulder extension and external rotation

Question 6

Supraspinatus

Answer 6

Origin: supraspinous fossa of the scapula

Insertion: superior facet on the greater tubercle of humerus

Innervation: suprascapular nerve (C5, C6)

Function: Rotator Cuff Muscle: initiation of abduction to 15 degrees at glenohumeral joint

Question 7

Infraspinatus

Answer 7

Origin: infraspinous fossa of the scapula

Insertion: middle facet on the posterior surface of greater tubercle of the humerus

Innervation: suprascapular nerve (C5, C6)

Function: Rotator Cuff Muscle: lateral rotation of the arm at the glenohumeral joint

Question 8

Teres Minor

Answer 8

Origin: lateral border of the scapula

Insertion: inferior facet of the greater tubercle of the humerus

Innervation: axillary nerve (C5, C6)

Function: Rotator Cuff Muscle: lateral rotation of the arm at the glenohumeral joint

Question 9

Subscapularis

Answer 9

Origin: subscapular fossa

Insertion: lesser tubercle of the humerus

Innervation: upper and lower subscapular nerves (C5, C6, C7)

Function: medial rotation of the arm at the glenohumeral joint

Question 10

Teres Major

Answer 10

Origin: inferior angle of the scapula

Insertion: crest of lesser tubercle of the humerus

Innervation: lower subscapular nerve (C5, C6, C7

Function: medial rotation and extension of the arm at the glenohumeral joint

Question 11

Coracobrachialis

Answer 11

Origin: apex of coracoid process of scapula

Insertion: midshaft of humerus

Innervation: musculocutaneous nerve (C5, C6, C7)

Function: flexor of the arm at the glenohumeral joint; adducts arm

Question 12

Biceps Brachii

Answer 12

Origin: long head - supraglenoid tubercle of the scapula; short head - apex of coracoid process

Insertion: tuberosity of radius

Innervation: musculocutaneous nerve (C5, C6)

Function: elbow flexion and supination; assists flexion of the shoulder

Question 13

Brachialis

Answer 13

Origin: anterior humerus and adjacent intermuscular septae

Insertion: tuberosity of the ulna

Innervation: musculocutaneous nerve (C6, C7); small contribution from radial nerve (C7)

Function: elbow flexion

Question 14

Triceps brachii

Answer 14

Origin: long head - infraglenoid tubercle of the scapula; medial head - posterior border of the humerus; lateral head - posterior surface of the humerus

Insertion: olecranon of ulna

Innervation: radial nerve (C6, C7, C8)

Function: elbow extension; long head can also extend and adducts the arm at the shoulder joint