Shoulder Muscles

Question 1

Supraspinatus

Answer 1

Suprascapular Nerve (C5,C6), Abduction of Humerus, Stabilizes Shoulder Joint

Question 2

Infraspinatus

Answer 2

Suprascapular Nerve (C5,C6), Lateral Rotation of Shoulder, Stabilizes Shoulder Joint

Question 3

Subscapularis

Answer 3

Subscapular Nerves (C5,C6), medial rotation of arm, adduction of arm

Question 4

Teres Minor

Answer 4

Axillary Nerve (C5, C6), Lateral Rotation of arm, weak adduction, stabilizes shoulder joint

Question 5

Rotator Cuff Muscles

Answer 5

Supraspinatus, Infraspinatus, Teres Minor, Subscapularis (SITS)

Question 6

Teres Major

Answer 6

Lower Subscapular Nerve (C5,C6), Medial Roatation, Adduction, Extension (Weak)

Question 7

Deltoid (ALL/Anterior only/Posterior only)

Answer 7

Axillary Nerve (C5,C6), ALL- Arm Abduction, ANTERIOR - Flexion and medial rotation, POSTERIOR - Extension and lateral roatation

Question 8

Trapezius (ALL, Superior, Middle, Inferior)

Answer 8

CN XI (motor), Branches of C3-C4(sensory), ALL- Retraction and Upward rotation of Scapula SUPERIOR- Elevation of Scapula, MIDDLE- Retraction of Scapula, INFERIOR- Depression of Scapula, Lowers Shoulder

Question 9

Latissimus Dorsi

Answer 9

Thoracodorsal Nerve (C6-C8), Arm extension, adduction, medial rotation

Question 10

Pectoralis Major (ALL, Clavicular, Sternocostal)

Answer 10

Lateral Pectoral N. (C5-C7), Medial Pectoral N. (C8,T1) ALL- Adduct and medial rotation, CLAVICULAR- Flexes Humerus STERNOCOSTAL- Extends Humerus

Question 11

Pectoralis Minor

Answer 11

Medial Pectoral N. (C8, T1) Stabilize scapula by drawing it inferiorly and anteriorly agains thoracic wall

Question 12

Levator Scapulae

Answer 12

Ventral Rami (C3-C4) Dorsal Scapular N. (C5), Elevation, Retraction, Downward rotation of scapula

Question 13

Rhomboid Minor

Answer 13

Dorsal Scapular N. (C5), Retraction, Elevation, and Downward rotation of scapula

Question 14

Rhomboid Major

Answer 14

Dorsal Scapular N. (C5), Elevation, Retraction, Downward rotation of scapula

Question 15

Serratus Anterior

Answer 15

Long thoracic Nerve (C5-7), Holds scapula against thoracic wall, protraction and upward rotation of scapula, assist shoulder abduction

Question 16

Shoulder Flexion

Answer 16

Pectoralis Major (clavicular portion), Deltoid (anterior fibers)

Question 17

Shoulder Extension

Answer 17

Deltoid (posterior fibers), Teres Major (weak), Latissimus Dorsi, Triceps Brachii (Long Head)

Question 18

Arm Abduction

Answer 18

Supraspinatus (Initiates 0-15deg), Deltoid (0-90deg), Trapezius and Serratus Anterior (Beyond 90 deg, scapular upward rotation)

Question 19

Shoulder Adduction

Answer 19

Pectoralis Major (adduct while flexing arm) Latissimus Dorsi (Adduct while extending arm) Together they produce adduction

Question 20

Medial (Internal Rotation) of Shoulder

Answer 20

SUBSCAPULARIS, latissimus Dorsi, Teres Major, Pectoralis Major, Deltoid (anterior fibers)

Question 21

Lateral (External) Rotation of Shoulder

Answer 21

Infraspinatus, Teres Minor, Deltoid (posterior fibers)

Question 22

Arm Circumduction

Answer 22

Subscapularis, supraspinatus, infraspinatus, latissimus dorsi, teres major, teres mino, pectoralis major, deltoid, coracobrachialis, biceps brachii, triceps (long head)

Question 23

Upward Scapular Rotation

Answer 23

Trapezius, serratus anterior

Question 24

Downward Scapular Rotation

Answer 24

Pectoralis Minor, Rhomboids

Question 25

Scapular Protraction

Answer 25

Serratus Anterior (prime mover), Pectoralis Minor

Question 26

Scapular Retraction

Answer 26

Rhomboid Major, Rhomboid Minor, Trapezius (middle fibers)

Question 27

Scapular Elevation

Answer 27

Trapezius (Upper Fibers), Levator Scapulae, Rhomboids

Question 28

Scapular Depression

Answer 28

Trapezius (lower fibers), Pectoralis Minor