Upper Extremity Myology Flashcards
Thoracoappendicular (anterior axioappendiclar) muscles
Pectoralis major M.
Pectoralis minor M.
Subclavius M.
Serratus anterior M.
Pectoralis Major M.
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
Pectoralis Minor M.
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
Subclavius M.
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
Serratus anterior M.
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.
“Winging” of the scapula
Results from an injury to the long thoracic N. Or the serratus anterior M.
Posterior axioappendicular muscles
Trapezius M. Latissimus dorsi M. Rhomboid Major M. Rhomboid Minor M. Levator Scapulae M.
Scapulohumeral Ms.
Deltoid M. Subscapularis M. Supraspinatus M. Infraspinatus M. Teres Minor M. Teres Major M.
Deltoid M.
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
Subscapularis M.
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.
Supraspinatus M.
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.
Infraspinatus M.
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.
Teres Minor M.
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.
Teres Major M.
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.
Triangular space
Borders: Teres Minor M., Teres major M., and long head of triceps brachii M.
Contents: Circumflex scapular A. And N.
Quadrangle space
Borders: Teres minor M., Teres major M., Long and Lateral heads of triceps brachii M.
Contents: Axillary N., Posterior humeral circumflex A. And V.
Triangular Interval
Borders: Teres Major M., Lateral and Long head of triceps brachii M.
Contents: Deep Brachial A. And V., Radial N.
Anterior compartment of Brachial muscles
Coracobrachialis M.
Biceps Brachii M.
Brachialis M.
Coracobrachialis M.
O: Coracoid process of scapula
I: medial aspect of the humeral body
A: Flex and ADduct humerus
N: Musculocutaneous N.
Biceps Brachii M.
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.
Brachialis M.
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.
Biceps tendinitis
Repetitive movement of long head of the Biceps T. Through the intertubercular groove causes inflammation
Popeye deformity
Biceps tendon separates entirely from origin and balls up in arm
Posterior compartment of Brachial Ms.
Triceps brachii M.
Aconeus M.
Triceps Brachii M.
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.
Anconeus M.
O: Lateral humeral epicondyle
I: Lateral aspect of olecrenon
A: with triceps brachii M. Extends the forearm, stabilizes elbow joint
N: Radial N.
Superficial Layer of Antebrachial Flexor Ms.
Pronator teres M.
Flexor carpi radialis M.
Palmaris Longus M. (Sometimes absent)
Flexor carpi ulnaris M.
Pronator Teres M.
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.
What common origin do all of the flexors of the forearm share?
Medial humeral epicondyle
What common origin do all of the extensors of the forearm share?
Lateral humeral epicondyle
Flexor carpi radialis M.
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.
Palmaris longus M.
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.
Flexor carpi ulnaris M.
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.
Flexor digitorum superficialis M.
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.
Deep layer of flexors of forearm
Flexor digitorum Profundus M.
Flexor pollicis Longus M.
Pronator quadratus M.
Flexor digitorum profundus M.
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.
Flexor Pollicis Longus M.
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.
Pronator Quadratus M.
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.
What is the anterior interosseus N. A branch of?
Median N.
What is the posterior interosseus N. A branch of?
Radial N. (Deep branch)
Superficial layers of extensors of the forearm
Brachioradialis M. EXtensor carpi radialis longus M. Extensor carpi radialis brevis M. Extensor Digitorum M. Extensor Digit Minimi M. Extensor Carpi Ulnaris M.
Brachioradialis M.
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.
Extensor carpi radialis longus M.
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.
Extensor carpi radialis brevis M.
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.
Extensor digitorum M.
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.
Extensor digiti minimi M.
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.
Extensor carpi ulnaris M.
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.
Elbow tendinitis
“Tennis elbow”
Pain over lateral epicondyle and down posterior forearm from repetitive use of superficial extensor muscles
Golfers elbow
Medial epicondyle strained and inflamed
Deep extensors of the forearm
Supinator M.
Extensor Indicis M.
Supinator M.
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.
Extensor Indicis M.
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.
Two radial nerve innervation
Brachioradialis
Extensor carpi radialis longus
Two deep radial nerve innervations
Extensor carpi radialis brevis and supinator
Posterior interosseus N.
Innervates all but 4 extensor muscles of the forearm
Outcropping muscles of the deep layers of extensors
Abductor pollicis longus M.
Extensor pollicis longus M.
Extensor pollicis brevis M.
Abductor pollicis longus M.
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.
Extensor pollicis Longus M.
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.
Extensor pollicis brevis M.
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.
Anatomical Snuff Box
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
Thenar eminence
Abductor pollicis brevis M.
Opponents Pollicis M.
Flexor pollicis brevis M.
Adductor Pollicis M.
Abductor Pollicis Brevis M.
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.
Opponens pollicis M.
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.
Flexor pollicis brevis M.
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.
Adductor Pollicis M.
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.
Hypothenar eminence
Abductor digiti minimi M.
Flexor digiti minimi brevis M.
Opponens digiti minimi M.
Abductor digiti minimi M.
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.
Flexor digiti minimi Brevis M.
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.
Opponens Digiti Minimi M.
Hypothenar eminence O: Hook of hamate and flexor retinaculum I: Medial aspect of 5th metacarpal A: Opposes 5th digit N: Deep ulnar N.
Intermediate Hand Muscles
Lumbricals
Dorsal Interossei M.
Palmar Interossei M.
Lumbrical Ms. 1-2
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.
Lumbrical Ms. 3-4
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.
Dorsal Interossei M.
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.
Palmar Interossei M.
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.
What nerve mostly innervates the forearm?
Median N.
What nerves mostly innervates the hand?
Ulnar N.
