Upper Limb Muscles Flashcards
pectoralis major
origin: anterior surfaces of clavicle and sternum; costal cartilages of ribs 1-6; aponeurosis of external oblique muscle
insertion: lateral lip of inter tubercular sulcus of humerus
action: flex and adduct arm; rotate arm medially
blood supply: pectoral branch of thoracoacromial artery; perforating branches of internal thoracic artery
innervation: medial and lateral pectoral nerves
pectoralis minor
origin: ribs 3-5 near costal cartilage
insertion: coracoid process of scapula
action: lowers lateral angle of scapula and protracts scapula
blood supply: pectoral branch of thoracoacromial artery
innervation: medial pectoral nerve
subclavius
origin: junction of 1st rib and its costal cartilage
insertion: inferior surface of middle third of clavicle
action: anchor and depress clavicle
blood supply: clavicular branch of thoracoacromial artery
innervation: subclavian nerve
serratus anterior
origin: lateral surfaces of ribs 1-8
insertion: anterior surface of medial border of scapula
action: protract and rotate scapula; hold scapula against thoracic wall
blood supply: lateral thoracic artery
innervation: long thoracic nerve
deltoid
origin: lateral third of the clavicle; acromion; spine of scapula
insertion: deltoid tuberosity of the humerus
action:
clavicular- flexes and medially rotates shoulder joint
acromial- abducts shoulder joint (after 15 deg.)
spinal- extends and laterally rotates shoulder joint
blood supply: posterior circumflex humeral artery; deltoid branch of thoracoacromial artery
innervation: axillary nerve
teres major
origin: posterior surface of the inferior angle of the scapula
insertion: medial lip of intertubercular sulcus of humerus
action: adducts and medially rotates shoulder joint
blood supply: circumflex scapular artery
innervation: lower subscapular nerve
teres minor
origin: middle part of lateral border of scapula
insertion: inferior facet of greater tubercle of humerus
action: laterally rotate shoulder joint; help hold humeral head in glenoid cavity
blood supply: circumflex scapular artery
innervation: axillary nerve
rotator cuff muscle
supraspinatous
origin: supraspinous fossa of scapula
insertion: superior facet of greater tubercle of humerus
action: initiate and assist deltoid with shoulder joint abduction
blood supply: suprascapular artery
innervation: suprascapular nerve
rotator cuff muscle
infraspinatous
origin: infraspinous fossa of scapula
insertion: middle facet of greater tubercle of humerus
action: laterally rotate shoulder joint; help hold humeral head in glenoid cavity
blood supply: suprascapular artery
innervation: suprascapular nerve
rotator cuff muscle
subscapularis
origin: subscapular fossa of scapula
insertion: lesser tubercle of humerus
action: medially rotate and adduct shoulder joint
blood supply: subscapular artery; lateral thoracic artery
innervation: upper and lower subscapular nerves
rotator cuff muscle
biceps brachii
origin: short head- coracoid process of scapula; long head- supraglenoid tubercle of scapula
insertion: radial tuberosity
action: flex elbow joint; supination
blood supply: brachial a.
innervation: musculocutaneous n.
brachialis
origin: middle part of anterior humerus
insertion: ulnar tuberosity
action: flex elbow joint in all positions
blood supply: brachial a.
innervation: musculocutaneous n.
coracobrachialis
origin: coracoid process of scapula
insertion: middle third of medial surface of humerus
action: adduct arm; flex arm at shoulder joint
blood supply: brachial a.
innervation: musculocutaneous a.
triceps brachii
origin: long head- infraglenoid tubercle of scapula; medial head- posterior surface of humerus, inferior to radial groove; lateral head- posterior surface of humerus, superior to radial groove
insertion: olecranon process
action: extend arm (long head), extend elbow
blood supply: deep brachial a.
innervation: radial n.
pronator teres
origin: humeral head- medial epicondyle of humerus; ulnar head- coronoid process of ulna
insertion: middle of lateral surface of radius
action: pronate and flex forearm
blood supply: anterior ulnar recurrent artery
innervation: median nerve
flexor carpi radialis
origin: medial epicondyle of humerus
insertion: base of 2nd metacarpal (index finger)
action: flex and abduct hand at wrist
blood supply: radial artery
innervation: median nerve
palmaris longus
origin: medial epicondyle of humerus
insertion: distal half of flexor retinaculum
action: flex hand at wrist
blood supply: posterior ulnar recurrent artery
innervation: median nerve
flexor carpi ulnaris
origin: olecranon and posterior border of ulna
insertion: pisiform and hook of hamate
action: flex and adduct hand at wrist
blood supply: posterior ulnar recurrent artery
innervation: ulnar nerve
flexor digitorum superficialis
origin: humero-ulnar head- medial epicondyle of humerus and coronoid process of ulna; radial head- oblique line of radius
insertion: bodies of middle phalanges of fingers
action: flex wrist joint and make “girly fist” (can’t flex distal phalanges)
blood supply: ulnar and radial arteries
innervation: median nerve
flexor digitorum profundus
origin: proximal 3/4 of medial and anterior surfaces of ulna
insertion: bases of distal phalanges
action: flex distal interphalangeal joints; flex wrist (make regular fist)
blood supply: anterior interosseous artery and ulnar artery
innervation: ulnar nerve (digits 4 and 5), median nerve (digits 2 and 3))
flexor pollicis longus
origin: anterior surface of radius and interosseous membrane
insertion: base of distal phalange of thumb
action: flex wrist and thumb (bring thumb into fist)
blood supply: anterior interosseous artery
innervation: median nerve (anterior interosseous nerve)
pronator quadratus
origin: distal 1/4 of anterior surface of ulna
insertion: distal 1/4 of anterior surface of radius
action: pronate forearm
blood supply: anterior interosseous artery
innervation: median nerve (anterior interosseous nerve)
brachioradialis
origin: lateral supraepicondylar ridge of humerus
insertion: lateral surface of distal end of radius proximal to the styloid process
action: weak flexion of elbow; main flexor of elbow when forearm is pronated
blood supply: radial recurrent a.
innervation: radial n.
extensor carpi radialis longus
origin: lateral epicondylar ridge of humerus
insertion: dorsal aspect of base of 2nd metacarpal
action: extend and abduct wrist
blood supply: radial a., radial recurrent a.
innervation: radial n.
extensor carpi radialis brevis
origin: lateral epicondyle of humerus
insertion: dorsal aspect of base of 3rd metacarpal
action: extend and abduct wrist
blood supply: radial a., radial recurrent a.
innervation: radial n.
extensor digitorum
origin: lateral epicondyle of humerus
insertion: extensor expansions of medial 4 fingers
action: extend wrist, extend fingers at metacarpophalangeal joints
blood supply: posterior interosseous a.
innervation: radial n. (posterior interosseous n.)
extensor digiti minimi
origin: lateral epicondyle of humerus
insertion: extensor expansion of 5th finger
action: extend wrist, extend pinky at metacarpophalangeal joint
blood supply: posterior interosseous a.
innervation: radial n. (posterior interosseous n.)
extensor carpi ulnaris
origin: lateral epicondyle of humerus, posterior border of ulna
insertion: dorsal aspect of of base of 5th metacarpal
action: extend and adduct wrist joint
blood supply: posterior interosseous a.
innervation: radial n. (posterior interosseous n.)
supinator
origin: lateral epicondyle of humerus, crest of ulna, radial collateral and annular ligaments
insertion: lateral, posterior, anterior surfaces of proximal 1/3 of radius
action: supinate forearm
blood supply: radial recurrent a., posterior interosseous a.
innervation: radial n.
abductor pollicis longus
origin: posterior surface of proximal 1/3 of ulna, radius, and interosseous membrane
insertion: base of 1st metacarpal (thumb)
action: extend wrist, abduct and extend thumb at carpometacarpal joint
blood supply: posterior interosseous a.
innervation: radial n. (posterior interosseous n.)
extensor pollicis longus
origin: posterior surface of middle 1/3 of ulna and interosseous membrane
insertion: dorsal aspect of base of distal phalanx of thumb
action: extend wrist, extend distal phalanx of thumb
blood supply: posterior interosseous a.
innervation: radial n. (posterior interosseous n.)
extensor pollicis brevis
origin: posterior surface of distal 1/3 of radius and interosseous membrane
insertion: dorsal aspect of proximal phalanx of thumb
action: extend wrist, extend proximal phalanx of thumb
blood supply: posterior interosseous a.
innervation: radial n. (posterior interosseous n.)
extensor incidis
origin: posterior surface of distal 1/3 of ulna and interosseous membrane
insertion: extensor expansion of 2nd finger (index)
action: extend wrist, extend 2nd finger (index)
blood supply: posterior interosseous a.
innervation: radial n. (posterior interosseous n.)
opponens pollicis
origin: flexor retinaculum and tubercles of scaphoid and trapezium
insertion: lateral side of 1st metacarpal
action: oppose thumb
blood supply: radial a. (superficial palmar branch)
innervation: recurrent branch of median nerve
abductor pollicis brevis
origin: flexor retinaculum and tubercles of scaphoid and trapezium
insertion: lateral side of base of proximal phalanx of thumb
action: abduct thumb
blood supply: radial a. (superficial palmar branch)
innervation: recurrent branch of median nerve
flexor pollicis brevis
origin: flexor retinaculum and tubercles of scaphoid and trapezium
insertion: lateral side of base of proximal phalanx of thumb
action: flex thumb
blood supply: radial a. (superficial palmar branch)
innervation: superficial head (recurrent branch of median nerve); deep head (deep branch of ulnar nerve)
adductor pollicis
origin: oblique head- base of 2nd and 3rd metacarpals and capitate; transverse head- anterior surface of shaft of 3rd metacarpal
insertion: medial side of base of proximal phalanx of thumb
action: adduct thumb
blood supply: deep palmar arch
innervation: deep branch of ulnar nerve
abductor digiti minimi
origin: pisiform
insertion: medial side of base of proximal phalanx of 5th finger
action: abduct 5th finger
blood supply: deep palmar branch of ulnar artery
innervation: deep branch of ulnar nerve
flexor digiti minimi brevis
origin: hook of hamate and flexor retinaculum
insertion: medial side of base of proximal phalanx of 5th finger
action: flex proximal phalanx of 5th finger
blood supply: deep palmar branch of ulnar artery
innervation: deep branch of ulnar nerve
opponens digiti minimi
origin: hook of hamate and flexor retinaculum
insertion: medial border of 5th metacarpal
action: brings pinky to opposition with the thumb
blood supply: deep palmar branch of ulnar artery
innervation: deep branch of ulnar nerve
lumbricals
origin: 1 & 2- lateral 2 tendons of flexor digitorum profundus; 3 & 4- medial 3 tendons of flexor digitorum profundus
insertion: lateral sides of extensor expansions of 2-5 fingers
action: flex metacarpophalangeal joints and extend interphalangeal joints of fingers 2-5
blood supply: superficial and deep palmar arches
innervation: median nerve (1 and 2), deep branch of ulnar nerve (3 and 4)
dorsal interossei
origin: adjacent sides of 2 metacarpals
insertion: lateral sides of extensor expansions of 2nd-5th fingers
action: abduct 2-4 fingers from axial line; act with lumbricals
blood supply: deep palmar arch
innervation: deep branch of ulnar nerve
palmar interossei
origin: palmar surfaces of 2, 4, 5 metacarpals
insertion: bases of proximal phalanges; extensor expansions of 2, 4, 5 fingers
action: adduct 2, 4, 5 fingers toward axial line; assist lumbricals
blood supply: deep palmar arch
innervation: deep branch of ulnar nerve
