Upper Extremity Myology

Question 1

Thoracoappendicular (anterior axioappendiclar) muscles

Answer 1

Pectoralis major M.
Pectoralis minor M.
Subclavius M.
Serratus anterior M.

Question 2

Pectoralis Major M.

Answer 2

O: clavicle, sternum, costal cartilages 1-6
I: lateral edge intertubercular groove of humerus
A: adduct and medially rotate humerus, protracts and depresses scapula, clavicular head flexes humerus, sternocostal head extends the humerus from the flexed state
N: Lateral AND medial pectoral Ns.
Blood supply: Thoracoacromial A, pectoral branch

Question 3

Pectoralis Minor M.

Answer 3

Deep to pectoralis major M.
O: Medial aspect of ribs
I: coracoid process of scapula
A: stabilizes scapula by protracting and depressing it against thoracic wall
N: medial pectoral N. (Pierced by this)
Blood supply: Thoracoacromial A., pectoral branch

Question 4

Subclavius M.

Answer 4

O: first rib and costal cartilage
I: inferior aspect of clavicle
A: positions and depresses the clavicle
N: Subclavius N.
Blood supply: Thoracoacromial A., clavicular branch

Question 5

Serratus anterior M.

Answer 5

O: lateral external surface of ribs
I: anterior surface of medial border of scapula
A: protracts scapula. Stabilizes against thoracic wall, rotates glenoid cavity superiorly
N: Long thoracic N.
A: Lateral thoracic A.

Question 6

“Winging” of the scapula

Answer 6

Results from an injury to the long thoracic N. Or the serratus anterior M.

Question 7

Posterior axioappendicular muscles

Answer 7

Trapezius M.
Latissimus dorsi M.
Rhomboid Major M.
Rhomboid Minor M.
Levator Scapulae M.

Question 8

Scapulohumeral Ms.

Answer 8

Deltoid M.
Subscapularis M.
Supraspinatus M.
Infraspinatus M.
Teres Minor M.
Teres Major M.

Question 9

Deltoid M.

Answer 9

O: Clavicle, scapular spine, acromion
I: deltoid tuberosity of humerus
A: Anterior part: flex and medially rotate humerus
Middle part: abduct humerus
Posterior part: extend and laterally rotate humerus
N: Axillary N.
Blood supply: Deltoid branch of thoracoacromial trunk

Question 10

Subscapularis M.

Answer 10

Rotator cuff
O: subscapular fossa
I: Lesser tubercle of humerus
A: medially rotate and ADduct humerus, holds humeral head in glenoid cavity
N: upper and lower subscapular Ns.
Blood supply: Subscapular A.

Question 11

Supraspinatus M.

Answer 11

Rotator cuff
O: Supraspinous fossa of scapula
I: Greater tubercle of humerus
A: ABduct humerus (with deltoid M.), holds the humeral head in glenoid cavity
N: Suprascapular N.
Blood supply: Suprascapular A.

Question 12

Infraspinatus M.

Answer 12

Rotator cuff
O: Infraspinous fossa of scapula
I: Greater tubercle of humerus
A: Lateral rotation, holds humeral head in glenoid cavity
N: Suprascapular N.
Blood supply: Suprascapular A.

Question 13

Teres Minor M.

Answer 13

Rotator cuff
O: Middle part of the lateral border of the scapula (superior)
I: Greater tubercle of humerus
A: Lateral rotation, holds the humeral head in the glenoid cavity
N: Axillary N.
Blood supply: Circumflex scapular A.

Question 14

Teres Major M.

Answer 14

O: Posterior aspect of inferior angle of scapula (inferior, larger)
I: Medial edge of Intertubercular groove of humerus (anterior)
A: ADdct and medially rotate humerus
N: Lower Subscapular N.
Blood supply: Circumflex scapular A.

Question 15

Triangular space

Answer 15

Borders: Teres Minor M., Teres major M., and long head of triceps brachii M.
Contents: Circumflex scapular A. And N.

Question 16

Quadrangle space

Answer 16

Borders: Teres minor M., Teres major M., Long and Lateral heads of triceps brachii M.
Contents: Axillary N., Posterior humeral circumflex A. And V.

Question 17

Triangular Interval

Answer 17

Borders: Teres Major M., Lateral and Long head of triceps brachii M.
Contents: Deep Brachial A. And V., Radial N.

Question 18

Anterior compartment of Brachial muscles

Answer 18

Coracobrachialis M.
Biceps Brachii M.
Brachialis M.

Question 19

Coracobrachialis M.

Answer 19

O: Coracoid process of scapula
I: medial aspect of the humeral body
A: Flex and ADduct humerus
N: Musculocutaneous N.

Question 20

Biceps Brachii M.

Answer 20

O: Long head-Supraglenoid tubercle of scapula
Short head-coracoid process of scapula
I: Radial tuberosity of humerus and antebrachial fascia as the bicipital aponeurosis
A: Flex humerus, flex supine forearm and supinate forearm, short head resists dislocation at the shoulder
N: Musculocutaneous N.

Question 21

Brachialis M.

Answer 21

O: Distal half of the anterior aspect of the humeral body
I: Ulnar tuberosity and coronoid process of ulna
A: Flex the forearm
N. Musculocutaneous N.

Question 22

Biceps tendinitis

Answer 22

Repetitive movement of long head of the Biceps T. Through the intertubercular groove causes inflammation

Question 23

Popeye deformity

Answer 23

Biceps tendon separates entirely from origin and balls up in arm

Question 24

Posterior compartment of Brachial Ms.

Answer 24

Triceps brachii M.

Aconeus M.

Question 25

Triceps Brachii M.

Answer 25

O: Long head-infraglenoid tubercle of scapula Lateral head- posterior aspect of the humeral body, superior to the radial groove Medial head- posterior aspect of the humeral body, inferior to the radial groove I: Olecrenon of ulna and antebrachial fascia A: Extend the forearm, long head resist dislocation of shoulder N: Radial N.

Question 26

Anconeus M.

Answer 26

O: Lateral humeral epicondyle I: Lateral aspect of olecrenon A: with triceps brachii M. Extends the forearm, stabilizes elbow joint N: Radial N.

Question 27

Superficial Layer of Antebrachial Flexor Ms.

Answer 27

Pronator teres M. Flexor carpi radialis M. Palmaris Longus M. (Sometimes absent) Flexor carpi ulnaris M.

Question 28

Pronator Teres M.

Answer 28

``` Superficial antebrachial flexor M. O: Humeral head-medial humeral epicondyle Ulnar head- coronoid process of ulna I: Lateral aspect of radius A: pronate and flex forearm N: Median N. ```

Question 29

What common origin do all of the flexors of the forearm share?

Answer 29

Medial humeral epicondyle

Question 30

What common origin do all of the extensors of the forearm share?

Answer 30

Lateral humeral epicondyle

Question 31

Flexor carpi radialis M.

Answer 31

Superficial antebrachial flexor M. O: Medial humeral epicondyle I: Ventral aspect of base of 2nd metacarpal A: flex forearm, flex and ABduct hand at wrist N: Median N.

Question 32

Palmaris longus M.

Answer 32

Superficial antebrachial flexor M. O: medial humeral epicondyle I: Palmar aponeurosis, flexor retinaculum A: flex forearm, flex hand and tenses palmar aponeurosis N: Median N.

Question 33

Flexor carpi ulnaris M.

Answer 33

Superficial Antebrachial Flexor M. O: Humeral head-medial humeral epicondyle ulnar head-olecrenon and posterior ulna I: Pisiform, hook of hamate, base of 5th metacarpal A: Flex forearm, flex and ADduct hand at the wrist N: Ulnar N.

Question 34

Flexor digitorum superficialis M.

Answer 34

Intermediate flexor of forearm O: Humeroulnar head-medial humeral epicondyle and coronoid process of ulna Radial head-superior half of anterior aspect of radius I: Bifed insertion on the intermediate phalanges of digits 2-5 A: flex forearm, flex hand at wrist, flex proximal and intermediate phalanges of digits 2-5 at the metacarpophalangeal and proximal interphalangeal joints N: Median N.

Question 35

Deep layer of flexors of forearm

Answer 35

Flexor digitorum Profundus M. Flexor pollicis Longus M. Pronator quadratus M.

Question 36

Flexor digitorum profundus M.

Answer 36

Deep flexor of forearm O: Proximal ulna and interosseus membrane I: ventral aspect of bases of distal phalanges of digits 2-5 (the tendon passes through the bifed tendon for the flexor digitorum superficial M to its insertion) A: flex hand at wrist, flex proximal, intermediate, and distal phalanges of digits 2-5 at metacarpophalangeal, proximal, and distal interphalangeal joints N: Lateral part: Anterior interosseus N. (Of the median N.) Medial part: ulnar N.

Question 37

Flexor Pollicis Longus M.

Answer 37

Deep flexor of the forearm O: Anterior aspect of the radius and interosseus membrane I: ventral aspect of the base of the distal phalanx of the Pollux A: Flex hand, flex and ABduct 1st metacarpal at the 1st carpometacarpal joint, flex both proximal and distal phalanges of the Pollux at the interphalangeal joints N: Anterior interosseus N.

Question 38

Pronator Quadratus M.

Answer 38

``` Deep flexor of the forearm O: Anterior aspect of the distal ulna I: anterior aspect of the distal radius A: pronate forearm, hold ulna and radius together N: Anterior interosseus N. ```

Question 39

What is the anterior interosseus N. A branch of?

Answer 39

Median N.

Question 40

What is the posterior interosseus N. A branch of?

Answer 40

Radial N. (Deep branch)

Question 41

Superficial layers of extensors of the forearm

Answer 41

``` Brachioradialis M. EXtensor carpi radialis longus M. Extensor carpi radialis brevis M. Extensor Digitorum M. Extensor Digit Minimi M. Extensor Carpi Ulnaris M. ```

Question 42

Brachioradialis M.

Answer 42

``` Superficial extensor of forearm O: Lateral humeral supracondylar ridge I: lateral aspect of the distal radius A: Flex forearm (most force when forearm is midpronated) N: Radial N. ```

Question 43

Extensor carpi radialis longus M.

Answer 43

Superficial extensor of forearm O: Lateral humera supracondylar ridge I: Dorsal aspect of the base of the 2nd metacarpal A: Extend and ABduct hand at the wrist (active during fist clenching) N: Radial N.

Question 44

Extensor carpi radialis brevis M.

Answer 44

``` Superficial extensor of forearm O: Lateral humeral epicondyle I: dorsal aspect of the base of the 3rd metacarpal A: extend and ABduct hand at the wrist N: Deep radial N. ```

Question 45

Extensor digitorum M.

Answer 45

``` Superficial extensor of the forearm O: lateral humeral epicondyle I: extensor expansions of digits 2-5 A: Extend hand at wrist, extend all phalanges of digits 2-5 at the metacarpophalangeal, proximal, and distal interphalangeal joints N: Posterior interosseus N. ```

Question 46

Extensor digiti minimi M.

Answer 46

``` Superficial extensor of the forearm O: lateral humeral epicondyle I: extensor expansion of digit 5 A: extend all phalanges at digit 5 at the metacarpophalangeal, proximal, and distal interphalangeal joints N: posterior interosseus N. ```

Question 47

Extensor carpi ulnaris M.

Answer 47

Superficial extensor of the forearm O: Lateral humeral epicondyle I: Dorsal aspect of the base of the 5th metacarpal A: Extend and ADduct hand at wrist (active during fist clenching) N: Posterior interosseus N.

Question 48

Elbow tendinitis

Answer 48

“Tennis elbow” | Pain over lateral epicondyle and down posterior forearm from repetitive use of superficial extensor muscles

Question 49

Golfers elbow

Answer 49

Medial epicondyle strained and inflamed

Question 50

Deep extensors of the forearm

Answer 50

Supinator M. | Extensor Indicis M.

Question 51

Supinator M.

Answer 51

``` Deep extensor of the forearm O: lateral humeral epicondyle, supinator crest and supinator fossa of ulna I: proximal aspect of the radial body A: supinate forearm N: deep radial N. ```

Question 52

Extensor Indicis M.

Answer 52

Deep extensor of the forearm O: posterior aspect of the distal ulna and interosseus membrane I: extensor expansion of digit 2 A: extend hand at wrist, extend 2nd digit N: Posterior interosseus N.

Question 53

Two radial nerve innervation

Answer 53

Brachioradialis | Extensor carpi radialis longus

Question 54

Two deep radial nerve innervations

Answer 54

Extensor carpi radialis brevis and supinator

Question 55

Posterior interosseus N.

Answer 55

Innervates all but 4 extensor muscles of the forearm

Question 56

Outcropping muscles of the deep layers of extensors

Answer 56

Abductor pollicis longus M. Extensor pollicis longus M. Extensor pollicis brevis M.

Question 57

Abductor pollicis longus M.

Answer 57

O: Posterior aspect of the proximal ulna, radius, and interosseus membrane I: Base of 1st metacarpal A: ABduct hand at wrist, ABduct pollex at the carpometacarpal joint N: Posterior interosseus N.

Question 58

Extensor pollicis Longus M.

Answer 58

O: Posterior aspect of ulna and interosseus membrane I: Dorsal aspect of the base of the distal phalanx of the pollex A: ABduct hand at wrist, extend 1st metacarpal, proximal, and distal phalanges of the pollex at all 3 joints N: posterior interosseus N.

Question 59

Extensor pollicis brevis M.

Answer 59

O: Posterior aspect of radius and interosseus membrane I: dorsal aspect of the base of the proximal phalanx of the pollex A: ABduct hand, extend 1st metacarpal and proximal phalanges of the pollex at carpometacarpal and metacarpophalangeal joints N: Posterior interosseus N.

Question 60

Anatomical Snuff Box

Answer 60

Lateral (anterior) border: Abductor pollicis longus M. And extensor pollicis Brevis M. Medial (posterior) border: Extensor pollicis longus M. Contents: Radial A. (Deep to tendon) and superficial radial N. Pain when pushing on this region is usually indicative of fractured scaphoid bone Falls on outstretched hands

Question 61

Thenar eminence

Answer 61

Abductor pollicis brevis M. Opponents Pollicis M. Flexor pollicis brevis M. Adductor Pollicis M.

Question 62

Abductor Pollicis Brevis M.

Answer 62

Part of thenar eminence O: tubercle of the scaphoid and trapezium bones and flexor retinaculum I: Lateral aspect of the base of the proximal phalanx of the pollex A: ABduct pollex, aids in opposition N: Recurrent branch of the Median N.

Question 63

Opponens pollicis M.

Answer 63

``` Thenar eminence O: Tubercles of the scaphoid and trapezium bones and flexor retinaculum I: Lateral aspect of the 1st metacarpal A: Oppose pollex N: Recurrent branch of the median N. ```

Question 64

Flexor pollicis brevis M.

Answer 64

Thenar eminence Superficial and deep head More medial than opponens pollicis M. And abductor pollicis M. O: Tubercles of the scaphoid and trapezium bones and flexor retinaculum I: lateral aspect of the base of the proximal phalanx of the pollex A: Flex 1st metacarpal and proximal phalanges of the pollex at the carpometacarpal and metacarpophalangeal joints N: Superficial head-recurrent branch of the median N. Deep head: deep ulnar N.

Question 65

Adductor Pollicis M.

Answer 65

Thenar eminence Oblique and transverse head O: Oblique head-capitate and bases of 2nd and 3rd metacarpal bones Transverse head-anterior aspect of the body of the 3rd metacarpal bone I: medial aspect of the proximal phalanx of the Pollux A: ADduct pollex N: deep ulnar N.

Question 66

Hypothenar eminence

Answer 66

Abductor digiti minimi M. Flexor digiti minimi brevis M. Opponens digiti minimi M.

Question 67

Abductor digiti minimi M.

Answer 67

``` Hypothenar eminence O: Pisiform bone I: Medial aspect of the base of the proximal phalanx of 5th digit A: ABduct 5th digit N: Deep ulnar N. ```

Question 68

Flexor digiti minimi Brevis M.

Answer 68

Hypothenar eminence O: Hook of hamate bone and flexor retinaculum I: Medial aspect of the base of the proximal phalanx of 5th digit A: flex proximal phalanx at 5th digit N: Deep Ulnar N.

Question 69

Opponens Digiti Minimi M.

Answer 69

``` Hypothenar eminence O: Hook of hamate and flexor retinaculum I: Medial aspect of 5th metacarpal A: Opposes 5th digit N: Deep ulnar N. ```

Question 70

Intermediate Hand Muscles

Answer 70

Lumbricals Dorsal Interossei M. Palmar Interossei M.

Question 71

Lumbrical Ms. 1-2

Answer 71

Intermediate muscles of hand O: lateral side of the arterial two flexor digitorum profundus tendons I: Radial aspect of the extensor expansions of the 2nd and 3rd digits A: flex proximal phalanges of the 2nd and 3rd digit at the metacarpophalangeal joint, extend intermediate and distal phalanges of the 2nd and 3rd digits by tightening extensor expansion N: Median N.

Question 72

Lumbrical Ms. 3-4

Answer 72

Intermediate muscles of hand O: Between the medial 3 flexor digitorum profundus tendons I: radial aspect of the extensor expansion of the 4th and 5th digits A: flex proximal phalanges of the 4th and 5th digits at the metacarpophalangeal joint, extend intermediate and distal of the 4th and 5th digits by tightening extensor expansion N: Deep Ulnar N.

Question 73

Dorsal Interossei M.

Answer 73

1-4 DAB O: adjacent sides of two metacarpals I: Bases of proximal phalanges and extensor expansion of digits 2-4 A: ABduct digits 2-4, flex proximal phalanges at the metacarpophalangeal joint, extend intermediate and distal phalanges by tightening extensor expansion N: deep ulnar N.

Question 74

Palmar Interossei M.

Answer 74

1-3 PAD O: palmar aspect of the 2nd, 4th, and 5th metacarpal bones I: Bases of proximal phalanges and extensor expansion of 2, 4, and 5th digits A: ADduct 2nd, 4th, and 5th digits, flex proximal phalanges (2,4, and 5) at the metacarpophalangeal joints, extend intermediate and distal phalanges (2,4, and 5) by tightening extensor expansion N: Deep Ulnar N.

Question 75

What nerve mostly innervates the forearm?

Answer 75

Median N.

Question 76

What nerves mostly innervates the hand?

Answer 76

Ulnar N.