Upper Extremity Muscles Flashcards
Trapezius
O. Upper: External occipital protuberance. Ligamentum nuchae
Middle: C7-T3 spinous processes
Lower: T4-T12 spinous processes
I. Upper: Lateral third of clavicle. Acromion of scapula
Middle: Spine of scapula
Lower: Root of spine of scapula
A. Upper: elevation. Lateral (uppward) rotation of scapula
Middle: adduction (retraction) of scapula
Lower: depression. Lateral (upward) rotation of scapula
N. Accessory n (CNXI) spinal part (motor). C3,4 spinal ns
Levator Scapula
O. C1-4 (transverse processes)
I. Vertebral border of scapula from superior angle to root of spine
A. Elevation. Medial (downward) rotation of scapula
N. Dorsal scapular n (C5). C3,4 spinal ns
Rhomboids Major
O: T2-T5 (spinous processes)
I: vertebral border of scapula from root of spine to inferior angle
A. Adduction (retraction). Medial (upward) rotation of scapula
N. Dorsal scapular n (C4,5)
Rhomboids Minor
O. C7-T1 (spinous processes)
I. root of spine of scapula
A. adduction (retraction). Medial (upward) rotation of scapula
N. Dorsal scapular n (C4,5)
Serratus Anterior
O. Lateral surface of upper 8 ribs (by finger-like slips)
I. Vertebral border of scapula - anterior surface
A. Abduction (protraction). Lateral (upward) rotation of scapula. Stabilizes scapula against chest wall. Depression of scapula (lower fibers). Assists forced exhalation.
N. Long thoracic n (C5,6,7)
Pectoralis Minor
O. Anterior surface of ribs 3,4,5 near costal cartilages
I. Coracoid process of scapula (medial boarder of superior surface)
A. Abduction (protraction). Depression. Medial (downward) rotation. Anterior tilt of scapula. Assists forced inhalation.
N Medial pectoral n (C8, T1)
Subclavius
O. 1st rib costocartilage junction
I. Inferior shaft of clavicle - middle 1/3
A. Depresses clavicle. Stabilizes sternoclavicular joint
N. Subclavian n (C5, 6)
Pectoralis Major
O. Clavicula head: medial half of clavicle
Sternocostal head: cartilages of superior 6 ribs. Aponeurosis of external oblique muscle.
I. Lateral lip of bicipital (intertubercular) groove of humerus
A. Adduction. Horizontal adduction. Medial rotation of humerus.
Clavical head: flexion of humerus
Sternocostal head: extension of humerus. Assists anterior tilt of scapula.
N. Clavicular head: lateral and medial pectoral ns (C5, 6)
Sternocostal head: medial pectoral n (C7, 8 T1)
Latissimus Dorsi
O. Thoracolumbar aponeurosis. Lower 6 thoracic spinous processes. Sacrum. Iliac crest of ilium. Lower 3 to 4 ribs. Inferior angle of scapula.
I. Bicipital (intertubercular) groove of humerus
A. Extension. Medial rotation. Adduction of humerus. Medial (downward) rotation of scapula. Assists depression of scapula.
N. Thoracodorsal n (C6,7,8)
Supraspinatus
O. Supraspinous fossa of scapula
I. Greater tubercle of humerus (superior facet)
A. Abdution. Scaption of humerus. Stabilization of head of humerus.
N. Suprascapular n (C4,5,6)
Infraspinatus
O. Infraspinous fossa of scapula
I. Greater tubercle of humerus (middle facet)
A. Lateral rotation. Extension of humerus
N. Suprascapular n (C5,6)
Teres Minor
O. Upper 2/3 of axillary border of scapula
I. Greater tubercle of humerus (inferior facet)
A. Lateral rotation. Extension of humerus
N. Axillary n (C5,6)
Subscapularis
O. Subscapular fossa of scapula
I. Lesser tubercle of humerus
A. Medial rotation. Adduction of humerus
N. Upper and lower subscapular ns (C5,6,7)
Teres Major
O. Inferior angle of scapula (dorsal surface). Lower third of axillary border of scapula
I. Medial lip of bicipital groove of humerus
A. Extension. Medial rotation. Adduction of humerus
N. Lower subscapular n (C5,6)
Deltoids
O. Anterior: lateral third of clavicle
Middle: Acromion of scapula - lateral surface
Posterior: spine of scapula
I. Deltoid tuberoisty of humerus
A. Anterior: Flexion. Horizontal adduction. Medial rotation of humerus
Middle: Abduction of humerus to 90 degrees
Posterior: Extension. Horizontal abduction. Lateral rotation. Scaption of humerus.
N. Axillary n (C5,6)
Coracobrachialis
O. Coracoid process of scapula
I. Middle 1/3 of medial surface of humeral shaft
A. Flexion. Adduction of humerus
N. Musculocutaneous n (C5,6,7)
Biceps Brachii
O. Short head: coracoid process of scapula
long head: Supraglenoid tubercle of scapula
I. Tuberosity of radius. Bicipital aponeurosis
A. Flexion of elbow. Supination of forearm.
Short head: flexion of humerus
N. Musculocutaneous n (C5,6)
Brachialis
O. Lower half of anterior shaft of humerus
I. Tuberosity of ulna. Coronoid process of ulna
A. Flexion of elbow
N Musculocutaneous n (C5,6)
Triceps Brachii
O. Long head: infraglenoid tubercle of scapula.
Lateral head: posterior humerus above spiral groove
Medial head: posterior humerus below spiral groove
I. Olecranon process of ulna
A. Extension of elbow
Long Head: Extension of humerus
N. Radial n (C6,7,8)
Anconeus
O. Lateral epicondyle of humerus
I. Olecranon process and upper posterior surface of ulna
A. Assists extension of elbow
N. Radial n (C7,8, T1)
Flexor Carpi Radialis
O. Medial epicondyle of humerus (common flexor tendon)
I. Bases of 2nd and 3rd metacarpals
A. Flexion. Abduction of wrist (radial deviation)
N. Median n (C6,7)
Flexor Carpi Ulnaris
O. Humeral head: medial epicondyle of humerus (common flexor tendon).
Ulnar head: proximal posterior ulna. Olecranon process of ulna
I. Pisiform carpal bone. Hamate carpal bone. Base of 5th metacarpal
A. Flexion. Adduction of wrist (ulnar deviation)
N. Ulnar n (C7,8)
Palmaris Longus
O. Medial epicondyle of humerus (common flexor tendon)
I. Palmar aponeurosis. Flexor retinaculum
A. assists flexion of wrist
N. Median n (C7,8)
Pronator Teres
O. Humeral Head: medial epicondyle of humerus
Ulnar head: coronoid process of ulna
I. Middle of lateral shaft of radius
A. Pronation of forearm. Assists in flexion of elbow
N. Median n (C6,7)
Pronator Quadratus
O. distal fourth of anterior ulna
I. Distal fourth of anterior radius
A. Pronates forearm
N. Median n (C8, T1)
Flexor Digitorum Superficialis
O. Humeroulnar head: medial epicondyle of humerus (common flexor tendon). Coronoid process of ulna
Radial head: anterior oblique line of radius
I. Sides of shafts of middle phalanges of 4 fingers
A. Flexion of 4 fingers at PIP joints. Assists flexion of wrist
N. Median n (C7,8,T1)
Flexor Digitorum Profundus
O. Proximal 3/4 of anterior ulna. Interosseous membrane
I. Bases of distal phalanges of 4 fingers
A. Flexion of 4 fingers at DIP joints. Assists flexion of wrist
N. Radial 2 fingers: Median n (C8, T1)
Ulnar 2 fingers: Ulnar n (C8, T1)
Flexor Pollicis Longus
O. Middle of anterior radius. Interosseous membrane
I. Distal phalanx of thumb
A. Flexion of thumb at IP joint
N. Median n (C8, T1)
Brachioradialis
O. Lateral supracondylar ridge of humerus
I. Styloid process of radius
A. Flexion of elbow with forearm in mid-position (halfway between supination and pronation)
N. Radial n (C5,6,7)
Extensor Carpi Radialis Longus
O. Lateral supracondylar ridge of humerus. Lateral epicondyle of humerus
I. Base of 2nd metacarpal
A. Extension. Abduction of wrist (radial deviation)
N. Radial n (C6,7)
Extensor Carpi Radialis Brevis
O. Lateral epicondyle of humerus (common extensor tendon)
I. Base of 3rd metacarpal
A. Extension of wrist
N. Radial n (C6,7)
Extensor Carpi Ulnaris
O. Humeral head: lateral epicondyle of humerus (common extensor tendon)
Ulnar head (deep to humeral head): posterior proximal ulna - subcutaneous border
I. Base of 5th metacarpal
A. Extension. Adduction of wrist (ulnar deviation)
N. Radial n (C7,8)
Extensor Digitorum
O. Lateral epicondyle of humerus (common extensor tendon)
I. Extensor expansion of 4 fingers
A. Extension of 4 fingers at MP joints. Assists extension of wrist
N. Radial n (C6,7,8)
Extensor Digiti Minimi
O. Lateral epicondyle of humerus (common extensor tendon)
I. Extensor expansion of little (5th) finger
A. Extension of little (5th) finger at MP joint. Assists extension of wrist
N. Radial n (C7,8)
Supinator
O. Lateral epicondyle of humerus. Annular ligament of radius. Radial collateral ligaments. Proximal ulna at supinator crest
I. Lateral surface of proximal 1/3 of radius between anterior and posterior oblique lines
A. Supination of forearm
N. Radial n (C7,8)
Extensor Indicis
O. Posterior ulna. Interosseous membrane
I. Extensor expansion of index (2nd) finger
A. Extension of index finger at MP joint. Assists extension of wrist.
N. Radial n (C7,8)
Abductor Pollicis Longus
O. Posterior radius. Posterior ulna. Interosseous membrane
I. Base of 1st metacarpal
A. abduciton of thumb at CM joint. Assist wrist abduction
N. Radial n (C7,8)
Extensor Pollicis Longus
O. Posterior ulna - middle 1/3. Interosseous membrane
I. Base of distal phalanx of thumb
A. Extension of thumb at IP joint. Assists wrist abduction
N. Radial n (C7,8)
Extensor Pollicis Brevis
O. Posterior radius. Interosseous membrane
I. Base of proximal phalanx of thumb
A. Extension of thumb at MP joint. Assists wrist abduction
N. Radial n (C7,8)
Abductor Pollicis Brevis
O. Flexor retinaculum. Trapezium carpal bone. Scaphoid carpal bone
I. Base of proximal phalanx of thumb - radia side
A. Abduction of thumb at CM joint
N. Median n (C8, T1)
Adductor Pollicis
O. Transverse head: Anterior shaft of 3rd metacarpal
Oblique head: base of 2nd and 3rd metacarpals. Capitate carpal bone. Trapezoid carpal bone. Trapezium carpal bone.
I. Base of proximal phalanx of thumb - medial side
A. Adduction of thumb at CM joint
N. Ulnar n (C8, T1)
Flexor Pollicis Brevis
O. Superficial Head: flexor retinaculum. Trapezium carpal bone.
Deep head: trapezoid carpal bone. Capitate carpal bone
I. Base of proximal phalanx of thumb - radial side
A. Flexion of thumb at MP joint
N. Superfical head: Median n (C8, T1)
Deep head: Ulnar n (C8, T1)
Opponens Pollicis
O. Flexor retinaculum. Trapezium carpal bone
I. Lateral shaft of 1st metacarpal
A. Opposition of thumb at CM joint
N. Median n (C8, T1)
Flexor Digiti Minimi Brevis
O. Flexor retinaculum. Hook of hamate carpal bone
I. Base of proximal phalanx of little (5th) finger
A. Flexion of little (5th) finger at MP joint
N. Ulnar n (C8, T1)
Opponens Digiti Minimi
O. Flexor rentinaculum. Hook of hamate carpal bone
I. Ulnar border of 5th metacarpal
A. Opposition of little (5th) finger at CM joint
N. Ulnar n (C8, T1)
Abductor Digiti Minimi
O. Pisiform carpal bone
I. Base of proximal phalanx of little (5th) finger at MP joint
A. Abduction of little (5th) finger at MP joint
N. Ulnar n (C8, T1)
Lumbricals (4)
O. Flexor digitorum profundus tendons
I. Extensor expansion of index, middle, ring, and little (2nd, 3rd, 4th & 5th) fingers at proximal phalanges - radial side
A. Flexion of fingers at MP joints. Extension of fingers at PIP and DIP joints
N. 1st and 2nd lumbricals (radial 2 fingers): Median n (C8, T1)
3rd and 4th lumbricals (ulnar 2 fingers): Ulnar n (C8, T1)
Palmar Interossei (3)
O. Shaft of 2nd , 4th and 5th metacarpals - palmar surface
I. Base of proximal phalanges to extensor expansion of index, ring, and little (2nd, 4th, 5th) fingers
A. Adduction of the index, ring, and little (2nd, 4th, 5th) fingers at MP joints. Assists lumbricals in MP flexion and PIP and DIP extension of index, middle, and ring (2nd, 3rd, 4th) fingers
N. Ulnar n (C8, T1)
Dorsal Interossei (4)
O. Each interosseous has 2 head arising from adjacent dorsal surfaces of metacarpals
I. Base of proximal phalanges to extensor expansion of index, middle, and ring (2nd, 3rd, 4th) fingers: Radial side of 2nd and 3rd. Ulnar side of 3rd and 4th
A. Abduction of index and ring (2nd and 4th) fingers and MP joints. Abduction and adduction of middle (3rd) finger at MP joints. Assists lumbricals in MP flexion and PIP and DIP extension of index, middle, and ring (2nd, 3rd, 4th) fingers
N. Ulnar n (C8, T1)
