Upper Extremity Myology

Question 1

Pectoralis Major M. (Provide Action Innervation and Blood Supply)

Answer 1

Action: Adduct & medially rotate humerus, Clav head: flex humerus, Sternocostal head: extend flexed humerus

Innervation: Medial/Lateral pectoral N.

Blood Supply: Pectoral branch of the thoracoacromial trunk

Question 2

Pectoralis Minor M.

Answer 2

Action: stabilize scapula by depression/protraction

Innervation: Medial pectoral N.

Blood Supply: Pectoral A. branch of the thoracoacromial trunk

Question 3

Subclavius M.

Answer 3

Action: Stabilize/depress clavicle

Innervation: Subclavian N.

Blood Supply: Clavicular A. branch of thoracoacromial trunk

Question 4

Serratus Anterior M.

Answer 4

Action: Protract Scapula, stabilize against thoracic wall, rotate glenoid cav sup.

Innervation: Long thoracic N.

Blood Supply: Lateral thoracic A.

Question 5

Deltoid M.

Answer 5

Action: Clavicular: flex & medially rotate humerous Acromial: abduct humerus Spinal: extened & laterally rotate humerous

Innervation: Axillary N.

Blood Supply: Deltoid A. branch of thoracoacromial A.

Question 6

Subscapularis M. (RC)

Answer 6

Action: Medially rotate, abduct humerous/ hold head in cavity

Innervation: Superior&Inferior subscapular N.

Blood Supply: Subscapular A.

Question 7

Supraspinatus M. (RC)

Answer 7

Action: Abduct and hold humerus head in glenoid cavity

Innervation: Suprascapular N.

Blood Supply: Suprascapular A.

Question 8

Infraspinatus M. (RC)

Answer 8

Action: Laterally rotate/hold humerus in glen cavity

Innervation: Suprascapular N.

Blood Supply: Suprascapular A.

Question 9

Teres Minor M. (RC)

Answer 9

Action: Laterally rotate/hold humerus in glenoid cavity

Innervation: Axillary N.

Blood Supply: Circumflex Scapular A.

Question 10

Teres Major M. (NOT RC)

Answer 10

Action: Adduct & medially rotate humerus

Innervation: Inferior subscapular N.

Blood Supply: Circumflex Scapular A.

Question 11

Biceps Brachii M.

Answer 11

Action: flex humerus, flex supine forearm, supinate forearm, resist shoulder dislocation (short head)

Innervation: Musculocutaneous N.

Blood Supply: Brachial A.

Question 12

Coracobrachialis M.

Answer 12

Action: Flex & adduct humerous

Innervation: Musculocutaneous N.

Blood Supply: Brachial A.

Question 13

Brachialis M.

Answer 13

Action: Flex forearm

Innervation: Musculocutaneous N.

Blood Supply: Brachial A., ruccurent Radial A.

Question 14

Triceps Brachii M.

Answer 14

Action: Extend forearm, extend/adduct humerus Long head: resist shoulder dislocation

Innervation: Radial N.

Blood Supply: Branches of deep Brachial A.

Question 15

Anconeus M.

Answer 15

Action: Extend forearm, stabilizes elbow joint, abducts the ulna during pronation

Innervation: Radial N.

Blood Supply: Middle collateral branch of deep brachial A.

Question 16

Pronator Teres M. (deep head and superficial head)

Answer 16

Action: Pronate & flex forearm

Innervation: Median N.

Blood Supply: Ulnar A.

Question 17

Flexor Carpi Radialis M.

Answer 17

Action: Flex and abduct hand at wrist

Innervation: Median N.

Blood Supply: Ulnar A.

Question 18

Palmaris Longus M.

Answer 18

Action: Flex hand at wrist, tense palmar aponeurosis

Innervation: Median N.

Blood Supply: Ulnar A.

Question 19

Flexor Capri Ulnaris M.

Answer 19

Action: flex and adduct hand at wrist

Innervation: Ulnar N.

Blood Supply: Ulnar A.

Question 20

Flexor Digitorum Superficialis M.

Answer 20

Action: Flex: forearm, hand at wrist, metacarpophalangeal joint, proximal interphalangeal joint

Innervation: Median N.

Blood Supply: Ulnar A.

Question 21

Flexor Digitorum Profundus M.

Answer 21

Action: Flex: hand at wrist, metacarpophalangeal, and proximal/distal interphalangeal joints

Innervation: Lateral: Anterior Interosseous N Medial: Ulnar N.

Blood Supply: Anterior interosseous A.

Question 22

Flexor Pollicis Longus M.

Answer 22

Action: Flex: hand at wrist, at 1st carpometacarpal, metacarpophalangeal, interphalangeal joint (THUMB)

Innervation: Anterior Interosseous N.

Blood Supply: Anterior Interossesous A.

Question 23

Pronator Quadratus M.

Answer 23

Action: Pronate forearm

Innervation: Anterior Interosseous N.

Blood Supply: Anterior interosseous A.

Question 24

Brachioradialis M.

Answer 24

Action: Flex forearm

Innervation: Radian N

Bloody Supply: Radial A.

Question 25

Extensor Carpi Radialis Longus M.

Answer 25

Action: extend and abduct hand at wrist Innervation: Radial N. Bloody Supply: Radial A.

Question 26

Extensor Carpi Radialis Brevis M.

Answer 26

Action: Extend/abduct hand at wrist Innervation: Deep radial N. Bloody Supply: Radial A.

Question 27

Extensor Digitorum M.

Answer 27

Action: Extend hand at wrist, metacarpophalangeal, proximal and distal interphalangeal joints Innervation: Posterior Interosseous N. Bloody Supply: Posterior Interosseous A.

Question 28

Extensor Digiti Minimi M.

Answer 28

Action: Extend metacarpophalangeal, proximal/distal interphalangeal joints Innervation: Posterior interosseous N. Bloody Supply: Interosseous A.

Question 29

Extensor Carpi Ulnaris M.

Answer 29

Action: Entend/adduct hand at wrist (ulnar flexion) Innervation: Posterior Interosseous N. Bloody Supply: Ulnar A.

Question 30

Supinator M.

Answer 30

Action: Suponates forearm Innervation: Deep Radial N. Bloody Supply: Interosseous A.

Question 31

Extensor Indicis M.

Answer 31

Action: Extend hand at wrist/extend index finger Innervation: Posterior Interosseous N. Bloody Supply: Posterior Interosseous A.

Question 32

Abductor Pollicis Longus M.

Answer 32

Action: Abduct hand/pollex (thumb) Innervation: Posterior Interosseous N. Bloody Supply: Posterior interosseous A.

Question 33

Extensor Pollicis Brevis M.

Answer 33

Action: Abduct hand at wrist/extend pollex (thumb) Innervation: Posterior Interosseous N. Bloody Supply: Posterior Interosseous A.

Question 34

Extensor Pollicis Longus M.

Answer 34

Action: Abduct hand at wrist/extend pollex (thumb) Innervation: Posterior Interosseous N. Bloody Supply: Posterior interosseous A.

Question 35

Abductor Pollicis Brevis M.

Answer 35

Action: Abduct pollex Innervation: Reccurent branch of median N. Bloody Supply: Superficial palmar arch , branch of the radial A.

Question 36

Flexor Pollicis Brevis M.

Answer 36

Action: Flex Pollex Innervation: Superficial head: recurrent branch of median N. Deep head: deep ulnar N. Bloody Supply: superficial palmar arch, branch of the radial A.

Question 37

Opponens Pollicis M.

Answer 37

Action: Oppose pollex Innervation: Reccurent branch of median N. Bloody Supply: superficial palmar arch branch of the radial A.

Question 38

Adductor Pollicis M. (oblique head(small) and transverse head)

Answer 38

Action: Adduct pollex Innervation: Deep ulnar N. Bloody Supply: Deep palmar arterial arch

Question 39

Abductor digiti minimi M.

Answer 39

Action: Abduct 5th digit Innervation: Deep ulnar N. Bloody Supply: Ulnar A.

Question 40

Flexor Digiti Minimi M.

Answer 40

Action: Flex proximal phalanx of 5th digit Innervation: Deep ulnar N. Bloody Supply: Ulnar A.

Question 41

Opponens Digiti Minimi M.

Answer 41

Action: Oppose 5th digit Innervation: Deep ulnar N. Bloody Supply: Ulnar A.

Question 42

1st, 2nd, 3rd, and 4th Lumbrical M.

Answer 42

Action: Flex metacarpophalangeal joint, extend proximal/distal interphalangeal joints Innervation: 1st/2nd Median N., 3rd/4th Deep Ulnar N. Bloody Supply: Dorsal and palmar metacarpal A.

Question 43

Dorsal Interossei MM. (1-4)

Answer 43

Action: Abduct 2nd digit laterally ,3rd both,4th medially, flex metacarpophalangeal joint (2-4), Extend proximal and distal interphalangeal joints (2-4) Innervation: Deep Ulnar Bloody Supply: Dorsal and palmar metcarpal A.

Question 44

Palmar Interossei MM. (1-3)

Answer 44

Action: Adduct 2nd digit medially, 4th and 5th laterally, flext metacarpophalangeal joint (2,4,5), Extend proximal/distal interphalangeal joints (2,4,5) Innervation: Deep Ulnar N. Bloody Supply: Palmar metacarpal A.