Exam 1 Muscles Flashcards
Descending Trapezius
Origin: spinous processes C1-C7, occipital bone
Insertion: clavicle (lateral 1/3)
Innervation: Spinal Accessory Nerve (CN11)
Action: draws scap upward, rotates glenoid cavity superiorly, tilts the head to the same side, rotates the head to the opposite side
Transverse Trapezius
origin: aponeurosis @ T1-T4 spinous processes
insertion: acromion
innervation: spinal accessory nerve (CN11)
action: draws scap medially
ascending trapezius
origin: spinous processes T5-T12
insertion: scapular spine
innervation: spinal accessory nerve (CN11)
action: draws scap medially downward
latissimus dorsi
origin: vertebral part –> spinous processes T5-T12, scapular part–> inferior angle of the scap, costal part –> ribs 9-12, iliac part –> iliac crest (posterior 1/3)
insertion: floor of the bicipital groove of the humerus
innervation: thoracodorsal nerve (C6-C8)
action: IR, Ext, ADD, respiration (cough muscle)
levator scapulae
origin: transverse processes of C1-C4
insertion: superior angle of the scapula on the medial border (b/w the superior angle and the superior portion of the spine)
innervation: dorsal scapular nerve (C4-C5)
action: draws scap medially upward while moving the inferior angle medially, inclines the neck to the same side
rhomboid major
origin: spinous processes T1-T4
insertion: medial border of scapula below the spine
innervation: dorsal scapular nerve (C4-C5)
action: steadies scap, draws scap medially upwards, retracts scap and tilts glenoid cavity inferiorly
rhomboid minor
origin: spinous processes of C6 and C7
insertion: posterior medial border of scapula @ the level of the spine
innervation: dorsal scapular nerve (C4-C5)
action: steadies scapula, draw scapula medially upwards, retracts the scapula and tilts the glenoid cavity inferiorly
deltoid
origin: clavicular part –> lateral 1/3 of clavicle, acromial part –> acromion, spinal part –> spine of the scapula
insertion: deltoid tuberosity of humerus
innervation: axillary nerve (C5,C6)
action: clavicular part –> flexion, IR, ADD, acromial part –> ABD, spinal part –> Ext, ER, ADD
supraspinatus
origin: supraspinous fossa of the scapula
insertion: greater tuberosity of humerus
innervation: suprascapular nerve (C4-C6)
action: ABD
infraspinatus
origin: infraspinous fossa of the scapula
insertion: greater tuberosity of the humerus
innervation: suprascapular nerve (C4-C6)
action: ER
teres minor
origin: lateral border of the scapula
insertion: greater tuberosity of the humerus
innervation: axillary nerve (C5-C6)
action: ER, weak ADD
subscapularis
origin: subscapular fossa
insertion: lesser tuberosity of humerus
innervation: upper and lower subscapular nerves (C5,C6)
action: IR
teres major
origin: inferior angle of the scapula
insertion: medial lip of the intertubercular sulcus of the humerus
innervation: lower subscapular nerve (C5-C7)
action: IR, ADD, EXT
pectoralis major (clavicular part)
origin: clavicle (medial half)
insertion: lateral border of the crest of the bicipital groove of the humerus
innervation: medial and lateral pectoral nerves (C5-T1)
action: shoulder ADD, IR, flexion, assist in respiration when the shoulder is fixed
pectoralis major (sternocostal part)
origin: sternum and costal cartilage of ribs 1-6
insertion: lateral border of the crest of the bicipital groove of the humerus
innervation: medial and lateral pectoral nerves (C5-T1)
action: shoulder ADD, IR, flexion, assist in respiration when the shoulder is fixed
pectoralis major (abdominal part)
origin: rectus sheath (anterior layer)
insertion: lateral border of the crest of the bicipital groove of the humerus
innervation: medial and lateral pectoral nerves (C5-T1)
action: shoulder ADD and IR
pectoralis minor
origin: ribs 3-5 near their costal cartilage
insertion: coracoid process of the scapula
innervation: medial pectoral nerve (C6-T1)
action: draws scapula downward –> inferior angle to move posteromedially , rotate glenoid cavity inferiorly, assist with respiration
subclavius
origin: first rib
insertion: inferior surface of clavicle
innervation: nerve to subclavius (C5,C6)
action: steadies the clavicle w/in the SC joint
serratus anterior
origin: first to ninth ribs
insertion: costal aspect of the medial border of the scapula
innervation: long thoracic nerve (C5-C7)
action: superior part –> lowers a raised arm
entire muscle –> protraction, elevates the ribs when the shoulder is fixed
inferior part –> rotates the scapula laterally
biceps brachii
origin: long head –> supraglenoid tubercle, short head: coracoid process
insertion: radial tuberosity and bicipital aponeurosis
innervation: musculocutaneous nerve (C5,C6)
action: elbow flexion and supination
shoulder flexion
humeral head –> stabilization during deltoid contraction, ABD and IR
brachialis
origin: humerus (distal half of anterior surface)
insertion: ulnar tuberosity
innervation: musculocutaneous nerve (C5,C6) and radial nerve (C7, minor)
action: elbow flexion
coracobrachialis
origin: coracoid process
insertion: humerus –> in line w/ crest of the lesser tuberosity
innervation: musculocutaneous nerve (C6,C7)
action: shoulder flexion, ADD, IR
triceps brachii
origin: long head –> infraglenoid tubercle
lateral head –> posterior humerus, proximal to radial groove and lateral intermuscular septum
medial head –> posterior humerus, distal to radial groove and medial intermuscular septum
insertion: olecranon of ulna
innervation: radial nerve (C6-C8)
action: elbow extension
long head –> shoulder extension and ADD
anconeus
origin: lateral epicondyle
insertion: olecranon of ulna
innervation: radial nerve (C7,C8,T1)
actions: assists with elbow extension, stabilizes elbow joint, ABD ulna during forearm pronation
pronator teres
origin: humeral head –> medial epicondyle, ulnar head –> coronoid process
insertion: radius (distal to supinator insertion point)
innervation: median nerve (C6,C7)
action: elbow flexion and forearm pronation
flexor carpi radialis
origin: medial epicondyle
insertion: base of 2nd metacarpal
innervation: median nerve (C6,C7)
action: wrist flexion and radial deviation (ABD)
palmaris longus
origin: medial epicondyle
insertion: palmar aponeurosis
innervation: median nerve (C6-C7)
action: weak elbow flexion, wrist flexion causes palmar aponeurosis to tighten
flexor carpi ulnaris
origin: humeral head –> medial epicondyle, ulnar head –> olecranon
insertion: pisiform, hook of hamate, base of 5th metacarpal
innervation: ulnar nerve (C8-T1)
action: wrist flexion, weak elbow flexion, ulnar deviation (ADD)
flexor digitorum superficialis
origin: humeral head –> medial epicondyle, ulnar head –> coronoid process
insertion: sides of the medial phalanges of digits 2-5
innervation: median nerve (C8,T1)
action: flexion of wrist, MCP joint, PIP joints and DIP joints of digits 2-5
flexor digitorum profundus
origin: proximal 2/3s of flexor surface of the ulna
insertion: distal phalanges of digits 2-5
innervation: medial sides of digits –> median nerve (C8-T1), ulnar sides of digits –> ulnar nerve (C8-T1)
action: flexion of wrist, MCP, PIP, DIP joints of digits 2-5
pronator quadratus
origin: distal quarter of ulnar (anterior surface)
insertion: distal quarter of radius (anterior surface)
innervation: median nerve (C7-C8)
action: hand pronation, stabilization of distal radioulnar joint
flexor pollicis longus
origin: radius (mid-anterior surface) adjacent to the interosseous membrane
insertion: distal phalanx of the thumb
innervation: median nerve (C7-C8)
action: radial deviation (ABD), wrist flexion, flexion of CMC, MCP and IP joints of the thumb
brachioradialis
origin: lateral supracondylar ridge of the distal humerus and the lateral intermuscular septum
insertion: styloid process of radius
innervation: radial nerve (C5,C6,C7)
action: elbow flexion and semipronation of the forearm
extensor carpi radialis longus
origin: lateral supracondylar ridge of the distal humerus and the lateral intermuscular septum
insertion: base of 2nd metacarpal
innervation: radial nerve (C6-C7)
action: wrist extension, radial deviation, weak elbow flexion
extensor carpi radialis brevis
origin: lateral epicondyle
insertion: base of 3rd metacarpal
innervation: radial nerve (C7-C8)
action: wrist extension, weak elbow flexion, radial deviation (ABD)
extensor digitorum
origin: lateral epicondyle
insertion: dorsal digit extensors of digits 2-5
innervation: radial nerve (C7-C8)
action: extension and ABD of fingers, wrist extension, extension of MCP, PIP and DIP joints of digits 2-5
extensor digiti minimi
origin: lateral epicondyle
insertion: dorsal digit extension of 5th digit
innervation: radial nerve (C7-C8)
action: ulnar deviation (ADD), wrist flexion, extension and ABD of MCP, PIP, DIP joints of 5th digit
extensor carpi ulnaris
origin: lateral epicondyle, ulnar head (dorsal surface)
insertion: base of 5th metacarpal
innervation: radial nerve (C7-C8)
action: wrist extension, ulnar deviation (ADD)
supinator
origin: olecranon, anular ligament, radial collateral ligament, lateral epicondyle
insertion: radius –> in b/w radial tuberosity and insertion for pronator teres
innervation: radial nerve (C6-C7)
action: radioulnar joint supination
Abductor pollocis longus
origin: dorsal surfaces of radius and ulna, interosseous membrane
insertion: base of 1st metacarpal
innervation: interosseous nerve (from deep branch of the radial nerve) (C7-C8)
action: ABD (radial deviation) of hand @ radiocarpal joint, ABD of CMC joint at thumb
extensor pollicis longus
origin: posterior surface of ulna and interosseous membrane
insertion: base of distal phalanx of the thumb
innervation: radial nerve C7-C8)
action: wrist extension, radial deviation (ABD) of hand, ADD of CMC joint at thumb, extension of MCP, PIP and DIP joints of thumb
extensor pollicis brevis
origin: posterior surface of the radius and interosseous membrane
insertion: base of proximal phalanx of the thumb
innervation: radial nerve (C7-C8)
action: radial deviation (ABD), MCP joint extension at thumb and CMC joint extension at thumb
extensor indicis
origin: posterior surface of the ulna and interosseous membrane
insertion: posterior digit extension of the 2nd digit
innervation: posterior interosseous nerve (from deep branch of radial nerve) (C7-C8)
action: wrist extension, extension of MCP, DIP, PIP joints of 2nd digit
abductor pollicis brevis
origin: scaphoid and trapezium and flexor retinaculum
insertion: base of the proximal phalanx of the thumb via the radial sesamoid
innervation: radial nerve (C8-T1)
action: ABD at CMC joint of thumb
flexor pollicis brevis
origin: superior head –> flexor retinaculum, deep head –> capitate and trapezium
insertion: base of the proximal phalanx of the thumb via the radial sesamoid
innervation: superficial head –> median nerve (C8-T1), deep head –> ulnar nerve (C8-T1)
action: CMC joint flexion of the thumb
Adductor pollicis
origin: transverse head–> 3rd metacarpal, oblique head –> capitate and bases of 2nd and 3rd metacarpals
insertion: base of first metacarpal of the thumb via the ulnar sesamoid
innervation: ulnar nerve (C8-T1)
action: CMC joint of thumb ADD, MCP joint of thumb flexion
Opponens Pollicis
origin: trapezium
insertion: radial border of the first metacarpal
innervation: medial nerve (C8-T1)
action: CMC joint of thumb opposition
abductor digiti minimi
origin: pisiform
insertion: ulnar base of the proximal phalanx of the 5th digit
innervation: ulnar nerve (C8-T1)
action: ABD of 5th digit, MCP joint flexion, PIP and DIP joint extension of 5th digit
flexor digiti minimi
origin: hook of hamate and flexor retinaculum
insertion: base of the proximal phalanx of the 5th digit
innervation: ulnar nerve (C8-T1)
action: MCP joint flexion of the 5th digit
opponens digiti minimi
origin: hook of hamate and flexor retinaculum
insertion: ulnar border of the 5th metacarpal
innervation: ulnar nerve (C8-T1)
action: draw metacarpal in palmar deviation (opposition)
dorsal interossei
origin: adjacent metacarpals 1-5
insertion: dorsal digital expansions of digits 2-5
innervation: ulnar nerve (C8-T1)
action: ABD of fingers away from the 3rd digit, MCP joint flexion, PIP and DIP joint extension of digits 2-5
palmar interossei
origin: 2nd, 4th, 5th metacarpals
insertion: dorsal digit expansions of digits 2,4,5
innervation: ulnar nerve (C8-T1)
action: ADD of fingers towards 3rd digit, MCP flexion and DIP,PIP extension of digits 2,4,5
lumbricals
origin: tendons for flexor digitorum profundus
insertion: dorsal digital expansions of digits 2-5
innervation: 1st and 2nd –> median nerve (C8-T1), 3rd and 4th –> ulnar nerve (C8-T1)
action: MCP joint flexion and DIP,PIP joint extension of digits 2-5