Upper Limb Muscles Flashcards
Subclavius
Prox - costochondral junction of the first rib
Dist - inferior surface of middle 1/3 clavicle
N: subclavian nerve C5 C6
stabilises the sternoclavicular joint and depression of lateral end of clavicle
Pectoralis minor
Prox: anterior and superior surfaces of ribs 3, 4, 5
Dist: coracoid process of scapula
N: medial and lateral pectoral nerves C5-8, T1
shoulder girdle depression, protraction and accessory muscle of respiration
Serratus anterior
Prox: anterior surface of medial border of scapula
Dist: lateral surfaces of upper 8-9 ribs
N: long thoracic nerve C5-7
shoulder girdle protraction and lateral rotation of scapula
Trapezius
Prox: superior nuchal line and external occipital protuberance, ligamentum nuchae, spinous processes of C7-T12, supraspinous ligament
Dist: lateral 1/3 clavicle (upper), acromion and spine of scapula (middle) and medial end of scapula spine (lower)
N: accessory nerve C3-C4
shoulder girdle elevation, retraction, depression and lateral rotation of scapula. Cervical side flexion and extension
Functional activity of the trapezius
Steadies scapula and clavicle against gravity - carrying weights
Provides fixation of neck/head - controls head position when leaning forwards e.g. reading and writing
Laterally rotates scapula - above head activity, like reaching
Retracts scapula - putting on a coat, pulling doors open
Depression of scapula against resistance - pushing up with hands from a seat
Levator scapulae
Prox: superior portion of the medial border of the scapula
Dist: transverse processes C1-4
N: dorsal scapular nerve C4-5
elevation of shoulder girdle, medial rotation of scapula, cervical extension and cervical side flexion
Rhomboid minor
Prox: spinous processes C7-T1, ligamentum nuchae
Dist: medial border of scapula at root of spine
N: dorsal scapular nerve C4-5
elevation and retraction of scapula
Rhomboid major
Prox: spinous processes T2-5 and intervening supraspinous ligaments
Dist: medial border of scapula from root of spine to inferior angle
N: dorsal scapular nerve C4-5
elevation and retraction of scapula
Brachialis
Prox: anterior aspect of humerus (medial and lateral surfaces) adjacent intermuscular septae
Dist: tuberosity of the ulna
N: musculocutaneous nerve C5-6
N: small contribution by the radial nerve C7 to lateral part of muscle
Powerful flexor of the forearm at the elbow
Biceps brachii
Prox: SHORT HEAD - coracoid process LONG HEAD - supraglenoid tubercle
Dist: radial tuberosity and bicipital aponeurosis
N: musculoscutaneous nerve C5-6
elbow flexion, supination. The long head causes shoulder flexion too
Brachioradialis
Prox: proximal aspect of lateral supraepicondylar ridge of humerus and adjacent intermuscular septum
Dist: lateral surface of distal end of radius
N: radial nerve C5-6
Accessory flexor of elbow joint when forearm is mid pronated
Returns forearm to mid range from full supination/pronation
Triceps brachii
Prox:
LONG HEAD - infraglenoid tubercle of scapula
MEDIAL HEAD - posterior surface of humerus
LATERAL HEAD - posterior surface of humerus
Dist: olecranon
N: radial nerve C6,7,8
extension at elbow, long head chases extension and abduction of humerus at the shoulder
Anconeus
Prox: lateral epicondyle of humerus
Dist: olecranon and proximal posterior surface of ulna
N: radial nerve C6,7,8
Abduction of ulna in pronation and accessory extensor of elbow joint
Pronator teres
Prox:
HUMERAL HEAD - medial epicondyle and adjacent supraepicondylar ridge
ULNAR HEAD - medial side of coronoid process
Dist: roughening on lateral surface, mid shaft of radius
N: median nerve C6,7
pronation
Pronator quadratus
Prox: linear ridge on distal anterior surface of ulna
Dist: distal anterior surface of radius
N: median nerve (anterior interosseous nerve C7,8)
probation and stabilises inferior radioulnar joint in weight bearing
Supinator
Prox:
SUPERFICIAL LAYER - lateral epicondyle of humerus, radial collateral and annular ligaments
DEEP LAYER - supinator crest of the ulna
Dist: lateral surface of radius superior to the anterior oblique line
N: posterior interosseous nerve C6,7
Supination
Pectoralis major
Prox:
CLAVICULAR HEAD - anterior surface, medial 1/2 clavicle
STERNOCOSTAL HEAD - anterior sternum, 1-7 costal cartilages, sternal end of 6th rib, aponeurosis of external oblique
Dist: lateral lip of intertubercular groove
N: medial and lateral pectoral nerves C5-8, T1
clavicular head - flexion
sternocistal head - extension
Adduction, medial rotation
Latissimus dorsi
Prox: thoracolumbar fascia, spinous processes T7-12, spinous processes lumbar/sacral spine, related interspinous ligaments, iliac crest, lower 3-4 ribs
Dist: floor of intertubercular groove
N: thoracodorsal nerve C6-8
shoulder extension, medial rotation and adduction
Deltoid
Prox:
ANTERIOR - anterior border, later 1/3 clavicle
MIDDLE - lateral margin of acromion
POSTERIOR - spine of scapula
Dist: deltoid tuberosity on mid shaft of humerus
N: axillary nerve C5-6
shoulder extension
Ant - shoulder flexion and medial rotation
Post - shoulder extension and lateral rotation
Coracobrachialis
Prox: apex of coracoid process
Dist: medial aspect, mid shaft of humerus
N: musculoscutaneous nerve C5-6
shoulder adduction and weak shoulder flexor
Teres major
Prox: posterior surface, inferior angle of scapula
Dist: medial lip of intertubercular groove
N: inferior sunscapular nerve C5-7
shoulder adduction and medial rotation
assists extension from flexed position
Suprapsinatus
Prox: medial 2/3 supraspinous fossa
Dist: superior facet on greater tubercle of humerus
N: suprascapular nerve C5-6
stabilises GHJ, assists in abduction of the shoulder
Infraspinatus
Prox: medial 2/3 infraspinous fossa
Dist: middle facet of greater tubercle of humerus
N: supra scapular nerve C5-6
stabilises GHJ, lateral rotation of shoulder
Teres minor
Prox: posterior surface, upper 2/3 lateral scapula
Dist: inferior facet on greater tubercle of humerus
N: axillary nerve C5-6
Stabilises GHJ and lateral rotation of shoulder
Subscapularis
Prox: medial 2/3 subscapular fossa
Dist: lesser tubercle of humerus
N: upper and lower subscapular nerve C5-7
stabilises GHJ and medial rotation of shoulder
Flexor carpi radialis
Prox: medial epicondyle of humerus
Dist: palmar surface of bases of metacarpals 2 and 3
N: median nerve C6,7
flexion and abduction at wrist
Palmaris longus
Prox: medial epicondyle of humerus
Dist: flexor retinaculum and apex of palmar aponeurosis
N: median nerve C7,8
weak wrist flexion and tightens palmar fascia
Flexor carpi ulnaris
Prox: medial epicondyle of humerus and medial border of olecranon and posterior border of ulna
Dist: pisiform, hook of hamate and base of metacarpal V
N: ulnar nerve C7,8
Flexion and adduction at the wrist
Synergic action in abduction of digit 5
Flexor digitorum superficialis
Prox: medial epicondyle of humerus and coronoid process of ulna, proximal 2/3 anterior border of radius
Dist: either side palmar surface of middle phalanx of each finger
N: median nerve (c8, t1)
flexion at the wrist, mcp and pip joints and tendon arrangement to increase grip power
Flexor digitorum profundus
Prox: medial side coronoid process, anteriomedial surfaces of the ulna and anterior 1/2 of interosseous membrane
Dist: base of palmar surface of distal phalanx of each finger
N: anterior interosseous nerve (C7-T1) and ulnar nerve (C8-T1)
flexion of dip, pip, mcp and wrist
Flexor pollicis longus
Prox: anterior surface of radius and adjacent interosseous membrane
Dist: palmar surface base of distal phalanx of thumb
N: anterior interosseous nerve (C7-8)
flexion at cmc, mcp, ip joint at thumb
Extensor carpi radialis longus
Prox: lateral supracondylar ridge of humerus
Dist: dorsal surface base of metacarpal 2
N: radial nerve (C6-7)
extension and radial deviation of wrist
Extensor carpi brevis
Prox: lateral epicondyle of humerus
Dist: dorsal surface base of metacarpal 2 and 3
N: posterior interosseous nerve (C7-8)
extension and radial deviation of wrist
Extensor carpi ulnaris
Prox: lateral epicondyle of humerus and shared aponeurosis from posterior ulna border
Dist: tubercle medial Sid of base of metacarpal 5
Nm posterior interosseous nerve (C7-8)
extension and ulnar deviation at wrist
Extensor digitorum
Prox: lateral epicondyle of humerus
Dist: bases and middle and distal phalanges of each finger
N: posterior interosseous nerve (C7-8)
extension of mcp at each finger
Assists extension of ip joints
Extensor digiti minimi
Prox: lateral epicondyle of humerus
Dist: dorsal digit expansion of digit 5
N: posterior interosseous (C7-8)
extension of mcp at little finger
assists extension of ip joints
Extensor indicis
Prox: posterior surface of distal ulna and interosseous membrane
Dist: dorsal digit expansion of index finger
N: posterior interosseous nerve (C7-8)
extension of ip and mcp in the index finger
Abductor pollicis longus
Prox: posterior surface of upper ulna, middle radius and intervening interosseous membrane
Dist: radial side of metacarpal 1
N: posterior interosseous nerve (C7-8)
Assists extension and abduction of the 1st carpometacarpal joint and abduction at the wrist
Extensor pollicis longus
Prox: posterior surface of middle 1/3 ulna and interosseous membrane
Dist: dorsal surface of base of distal phalanx of thumb
N: posterior interosseous nerve (C7-8)
extension at ip joint
assists extension at mcp, cmc and wrist
Extensor pollicis brevis
Prox: posterior surface of middle ulna and interosseous membrane
Dist: dorsal surface of base of proximal phalanx of thumb
N: posterior interosseous nerve (C7-8)
extension of mcp and cmc joints
Abductor pollicis brevis
Prox: tubercles of scaphoid, trapezium and adjacent flexor retinaculum
Dist: proximal phalanx and extensor hood of the thumb
N: median nerve (C8-T1)
abducts thumb at metacarpoohalangeal and carpometacarpal joint
Flexor pollicis brevis
Prox: tubercle of the trapezium and flexor retinaculum
Dist: proximal phalanx of the thumb
N: median nerve (C8-T1)
flexes thumb at mcp and cm joints
Openens pollicis
Prox: tubercle of trapezium and flexor retinaculum
Dist: lateral margin and adjacent palmar surface of metacarpal 1
N: median nerve (C8-T1)
medial rotation of thumb
Adductor pollicis
Prox:
transverse head; metacarpal 3
Oblique head; capitate and base of metacarpals 2 and 3
Dist: base of proximal phalanx and extensor hood of the thumb
N: ulnar nerve (C8-T1)
adducts thumb
Abductor digiti minimi
Prox: pisiform, pisohamate ligament, tendon of flexor carpi ulnaris
Dist: proximal phalanx of the little finger
N: ulnar nerve (C8-T1)
abducts little finger at mcp joint and flexion
Flexor digiti minimi
Prox: hook of hamate and flexor retinaculum
Dist: proximal phalanx of little finger
N: ulnar nerve (C8-T1)
flexes little finger at mcp joint
Opponens digiti minimi
Prox: hook of hamate and flexor retinaculum
Dist: medial aspect of metacarpal 5
N: ulnar nerve (C8-T1)
laterally rotates metacarpal 5 and opposition of the 5th digit
Palmaris brevis
Prox: palmar aponeurosis and flexor retinaculum
Dist: dermis of skin on medial margin of hand
N: ulnar nerve (C8-T1)
improves grip
Lumbricals
Prox: tendons of flexor digitorum profundus
Dist: extensor hoods of index, ring, middle and little fingers
N: medial two by deep branch of the ulnar nerve, lateral two by the digital branches of the median nerve
flex mcp joints while extending ip joints
Palmar interossei
Prox: sides of metacarpals
Dist: extensor hoods of the thumb, index, ring and little fingers and the proximal phalanx of the thumb
N: ulnar nerve (C8-T1)
adduction of the thumb, index, ring and little fingers at the mcp joints
Dorsal interossei
Prox: adjacent sides of metacarpals
Dist: extensor hoods and base of proximal phalanges of index, middle and ring fingers
N: ulnar nerve (C8-T1)
abduction of index, middle and ring fingers at the mcp
