Appendicular muscles

Question 1

Pectoralis minor

Answer 1

Origin: sternal ends of upper ribs

insertion: coracoid process of scapula
action: protracts and depresses the scapula (when your shoulders are hunched forward, the pectoralis minor muscles is contracting)

Question 2

Serratus anterior

Answer 2

Origin: anterior and superior margins of upper ribs
Insertions: medial (vertebral) border of scapula and anterior surface of scapula
Action: prime mover that protracts and depresses scapula (synergistic to pectoralis minor), stabilizes the scapula, and superiorly rotates scapula

Question 3

Rhomboid major

Answer 3

Origin: spinous processes of T2-T5
Insertion: medial (vertebral) border of scapula
Action: retracts (adducts) and elevates scapula, and inferiorly rotates scapula

Question 4

Rhomboid minor

Answer 4

Origin: spinous processes of C7-T1
Insertion: medial (vertebral) border of scapula
Action: retracts (adducts) and elevates scapula, and inferiorly rotates scapula

Question 5

Trapezius

Answer 5

Origin: occipital bone (superior nuchal line), ligamentum nuchae, and spinous processes of C7-T12
Insertion: clavicle, acromion process, and spine of scapula
Action: elevates and retracts (adducts) the scapula, draws head back.

Question 6

Latissimus dorsi

Answer 6

Origin: spinous processes of T7-T12, many of the lower ribs, iliac crest, and thoracolumbar fascia
Insertion: intertubercular groove of proximal humerus
Action: prime mover of arm extension and also draws the arm downward and backward while it rotates medially

Question 7

Pectoralis major

Answer 7

Origin: medial clavicle, costal cartilages of upper ribs, body of sternum
Insertion: lateral part of intertubercular groove of proximal humerus
Action: prime mover of arm flexion; also adducts and medially rotates arm

Question 8

Deltoid

Answer 8

Origin: acromial end of clavicle, the acromion, and the spine of the scapula
insertion: deltoid tuberosity on lateral mid region of humerus
Action: anterior fibers flex and medially rotate arm; middle fibers prime mover of arm abduction; posterior fibers extend and laterally rotate arm

Question 9

Teres major

Answer 9

Origin: inferior lateral border and inferior angle of scapula
insertion: lesser tubercle and intertubercular groove at lateral proximal end of humerus
Action: Prime mover of arm extension and also draws the arm downward and backward while it rotates medially

Question 10

Coracobrachialis

Answer 10

origin: coracoid process of scapula
insertion: middle medial shaft of humerus
action: adducts and flexes arm

Question 11

Rotator cuff muscles

Answer 11

Subscapularis, supraspinatus, infraspinatus, teres minor

Question 12

Subscapularis

Answer 12

Origin: subscapular fossa of scapula
Insertion: lesser tubercle of humerus
Action: medially rotates arm, like when you wind up to pitch a baseball

Question 13

Supraspinatus

Answer 13

Origin: supraspinous fossa of scapula
insertion: greater tubercle of humerus
Action: abducts the arm as when you execute a pitch of a baseball, with your arm fully abducted.

Question 14

INfraspinatus

Answer 14

Origin: infraspinous fossa of scapula
INsertion: greater tubercle of humerus
Action: adducts and laterally rotates the arm, like when you slow down your arm after pitching a baseball

Question 15

teres minor

Answer 15

Origin: lateral border of scapula
Insertion: greater tubercle of humerus
Action: synergistic to infraspinatus