Upper Extremity Muscles

Front 1

biceps brachii

Back 1

Innervation: musculocutaneous nerve C5 C6
O: long head = supraglenoid tubercle. short head = coracoid process
I: radial tuberosity & deep anterebrachial fascia
Blood Supply: brachial artery
ACTION -flexion of arm and forearm, supination of forearm

Front 2

coracobrachialis

Back 2

O: coracoid process
I: medial proximal shaft of humerus.
Innervation: musculocutaneous nerve
Blood Supply: Brachial artery

Front 3

Triceps

Back 3

Innervated by radial nerve C7 C8
O: long head =infraglenoid tubercle of scapula; medial head = distal posteromedial shaft of humerus, lateral head = proximal and posterolateral shaft of humerus.
I: olecranon process of ulna
Nerve: radial
blood:deep brachial artery
ACTION - extends forearm, extend arm

Front 4

Deltoid

Back 4

Innervated by C5 C6, axillary nerve
O:clavicle acromion and spine of scapula
I: deltoid tuberosity of humerus
blood - Posterior Humeral Circumflex artery
ACTION - humeral flexion, medial rotation, abduction, extension and lateral rotation

Front 5

Brachialis

Back 5

Innervated by musculocutaneous and radial nerves
O: distal anterior shaft of humerus
I: coronoid process and ulnar tuberosity
blood - radial recurrent artery
ACTION - flexion of forearm

Front 6

Abductor Digit minimi

Back 6

Innervated by deep branch of ulnar nerve
O: pisiform
I: ulnar side of base of 5th digit
blood - ulnar artery
ACTION - Abducts the pinky

Front 7

Abductor Pollicis Brevis

Back 7

Innervated by recurrent branch of median nerve C8 T1.
O:flexor retinaculum
I: radial side of base of proximal phalanx of thumb
blood - superficial palmar arch artery

Front 8

Adductor Pollicis

Back 8

Innervated by deep branch of ulnar nerve C8 T1
O: capitate and 2nd, 3rd metacarpals and palmar aspect of 3rd metacarpal
I: base of proximal phalanx of thumb
blood - deep palmar arterial arch
ACTION - adducts thumb

Front 9

Dorsal Interossei

Back 9

Innervated by deep branch of the ulnar nerve C8 T1
O: adjacent sides of metacarpals
I: proximal phalangeal bases and dorsal digital expansions of digits 2-4.
blood - deep metacarpal artery and palmar metacarpal artery
ACTION -abducts and flexes MP, extends IP digits 2-4

Front 10

Flexor digiti minimi brevis

Back 10

innervated by deep branch of the ulnar nerve C8 T1
O: hamate
I: ulnar side of the base of the proximal phalanx of the 5th digit
blood - ulnar artery
ACTION - flexes 5th digit MP

Front 11

Flexor Pollicis Brevis

Back 11

Innervated by recurrent branch of medial nerve and deep branch of ulnar nerve. C8 T1
O: floor of retinaculum and trapesium
I: radial side of base of proximal phalanx of thumb
blood - superficial palmar branch of radial artery

Front 12

Lumbricals

Back 12

Innervated by deep branch of ulnar nerve (medial 2 lumbricals) and median nerve (lateral two lumbricals) C8 T1
O: tendons of flexor digitorum profundus
I: radial side of dorsal digital expansions of digits 2-5
blood - superficial palmar arterial arch
ACTION - flex MP joints, extend IP joints

Front 13

Opponens digiti minimi

Back 13

Innervated by deep branch of ulnar nerve C8 T1
O: hook of hamate
I: ulnar margin of shaft of 5th matacarpal
Blood - ulnar artery

Front 14

Opponens pollicis

Back 14

Innervated by recurrant branch of median nerve C8 T1
O: flexor retinacular and trapezium
I: palmar surface of 1st metacarpal
blood - superficial palmar branch of radial artery

Front 15

Palmar Interossei

Back 15

Innervated by deep branch of ulnar nerve C8 T1
O: palmar aspects of metacarpals 2,4,5
I: Dorsal digital expansions of digits 2,4,5
blood - dorsal and palmar metacarpal arteries
ACTION -adducts and flexes (MP) and extends IP digits 2,4,5

Front 16

Some lovers try positions that they can't handle

scaphoid. lunate. triquetrim. pisiform. trapesium. trapezoid. capitate. hamate.

Back 16

Mnemonic for carpal (wrist) bones

Front 17

Brachioradialis

Back 17

Innervated by radial nerve.
O: lateral supracondylar ridge of humerus
I: distal radius adjacent to styloid process
blood - radial recurrent artery
ACTION - flexion of forearm

Front 18

Pronator Teres

Back 18

Innervated by median nerve.
O: medial epicondyle and ulnar coronoid process
I: lateral aspect of radius
blood - ulnar and radial arteries.
ACTION - pronates and flexes forearm

Front 19

Flexor Carpi Radialis

Back 19

Innervated by the median nerve
O: (common flexor origin) on medial epicondyle of humerus
I: palmar aspect of bases of 2nd and 3rd metacarpal.
blood - ulnar artery
ACTION - flexes and abducts hand and wrist

Front 20

palmaris longus

Back 20

Innervated by median nerve.
O: medial epicondyle (commone flexor tendon)
I: palmar aponeurosis
blood - ulnar artery
ACTION - flexes hand at wrist
absent in ~%14 of population

Front 21

Flexor Carpi Ulnaris

Back 21

innervated by ulnar nerve
O: common fleoxr tendon at medial epicondyle and proximal ulnar shaft.
I:pisiform
blood - ulnar artery
ACTION - adducts and flexes hand at wrist

Front 22

Flexor Digitorum Superficialis

Back 22

Innervated by median nerve
O: humeral medial epicondyle
I: sides of middle phalanges of digits 2-5.
blood - ulnar artery
ACTION - flexes digits MP and proximal IP and hand at wrist

Front 23

Flexor Digitorum Profundus

Back 23

Innervated by median and ulnar nerve.
O: anterior proximal ulna and interosseous membrane.
I: base of distal phalanges 2-5
blood - anterior interosseous artery
ACTION - flexes digits 2-5 and hand at wrist

Front 24

extensor carpi ulnaris

Back 24

Innervated by radial nerve.
O: lateral epicondyle of humerus
I: base of 5th metacarpal
blood - ulnar artery
ACTION - extends and adducts hand at wrist.

Front 25

Extensor Digitorum

Back 25

Innervated by radial nerve
O: lateral epicondyle of humerus (common extensor origin)
I: extensor expansions of digits 2-5
blood - interosseous recurrent and posterior arteries
ACTION - extends digits 2-5 and hand at wrist

Front 26

Supinator

Back 26

Innervated by radial nerve.
O: lateral epicondyle of humerus, radial collateral lig and supinator crest of ulna
I:lateral surface of proximal radius
blood - radial recurrent artery
ACTION - supinates forearm

Front 27

Extensor Pollicis Longus

Back 27

Innervated by radial nerve
O: middle 1/3 or posterior ulna and inteross.
I: base of distal phalanx of thumb
blood - posterior interosseous artery
ACTION - extends thumb MP and IP.

Front 28

Abductor Pollicis Longus

Back 28

Innervated by radial nerve
O: prox posterior radius ulna and inteross membrane
I: ant base of 1st metacarp and trapezium.
blood - posterior inteross. artery
ACTION - abducts and extends thumb at carpometacarpal joint.