Superficial Back and Upper Extremity Flashcards
Trapezius (superior fibers)
O: External occipital protuberance, the medial portion of superior nuchal line of occiput, medial margin of ligamentum nuchae,
I: Posterior border of lateral 1/3 of the clavicle
A: Unilaterally: Elevation and upper rotation of the scapula; ipsilateral side bending (laterally flex) and contralateral rotation of the head;
Bilaterally: extend the head and neck
N: Accessory nerve (CN XI) and branches of C3, C4
Trapezius (middle fibers)
O: Inferior aspect of ligamentum nuchae, spinous proces of 7th cervical and upper thoracic
I: Medial margin of acromion process of scapula, superior lip of posterior border of spine of
scapula
A: Retraction of scapula, adduct scapula, stabilize scapula
N: CN XI and C3, C4
Trapezius (inferior fibers)
O: Spinous process of inferior thoracic vertebrae
I: Medial end of the spine of scapula
A: Depression of the scapula, upwardly rotate the scapula
N: CN XI and C3, C4
Rhomboid Major:
O: Spinous processes of T2 - T5 vertebrae
I: Posterior surface of medial border of scapula from the root of the spine of the scapula to the
inferior angle
A: Elevates and retracts the scapula, adduct the scapula, downwardly rotate the scapula
N: Dorsal scapular nerve (C4-C5)
Rhomboid Minor:
O: Lower end of ligamentum nuchae and spinous process of C7 and T1 vertebrae
I: Posterior surface of medial border of scapula at the root of the spine of the scapula
A: Elevates and retracts the scapula, adduct the scapula, downwardly rotate the scapula
N: Dorsal scapular nerve (C4-C5)
Levator Scapulae
O: Transverse processes of C1-C4 vertebrae at the posterior tubercles
I: Posterior surface of medial border of scapula from superior angle to root of spine of the scapula
A: Unilaterally: Elevates scapula; ipsilateral side bending and ipsilateral rotation of the head, downwardly rotate the scapula
Bilaterally: extend the head and neck
N: Anterior rami of C3 and C4 spinal nerves and by branches (C5) from the dorsal scapular nerve
Latissimus Dorsi
O: Spinous processes of T7-T12 and related interpinous ligaments; via the thoracolumbar fascia to
the spinous process of the lumbar vertebrae, related interspinous ligaments, and posterior iliac crest; last three or four ribs, inferior angle of the scapula
I: Floor of the intertubercular sulcus (or groove)
A: Adduction, medial rotation, and extension of the arm at glenohumeral joint,
N: Thoracodorsal nerve (C6,C7,C8)
Teres Major
O: Lower one third of lateral border of the scapula
I: Medial lip of intertubercular sulcus on the anterior surface of the humerus; crest of the lesser tubercle of the humerus
A: Medial rotation, extension of the arm, and adduction at the glenohumeral joint
N: lower subscapular nerve (C5, C6)
Deltoid (posterior fibers)
O: Inferior edge of the crest of the spine of the scapula
I: Deltoid tuberosity of the humerus
A: Abduct, extension, horizontal abduction, external rotation - humerus
N: Axillary (C5, C6)
Deltoid (middle fibers)
O: Lateral margin of the acromion
I: Deltoid tuberosity of the humerus
A: Abduction of humerus
N: Axillary (C5, C6)
Deltoid (anterior fibers)
O: Anterior border of the lateral 1/3 of clavicle
I: Deltoid tuberosity of the humerus
A: Abduct, flexion, horizontal adduction, internal rotation of the humerus
N: Axillary (C5, C6)
Pectoralis major
O: Clavicular head - anterior surface of medial half of clavicle;
Sternocostal head - anterior surface of the sternum; first seven costal cartilages; sternal end of the sixth rib; aponeurosis of external oblique
I: Lateral lip of the intertubercular sulcus of humerus; crest of greater tubercle of humerus
A: All fibers: adduction of glenohumeral (GH) joint, and medial rotation of glenohmeral joint; assist to elevate the thorax during forced inhalation with arm fixed; horizontal adduction of GH joint
Clavicular head: flexion of the extended shoulder
Sternocostal head: extension of the flexed shoulder
N: Medial and lateral pectoral nerves (C5-T1)
Clavicular head: lateral pectoral (C5, C6)
Sternocostal head: lateral and medial pectoral nerves (C7, C8, T1)
Pectoralis minor
O: Anterior surface of the superior borders of third to fifth ribs; and from deep fascia overlying the
related intercostal spaces
I: Coracoid process of scapula (medial border and upper surface)
A: Stabilization of the scapula against thoracic wall by pulling the coracoid process anteriorly,
downward rotation of the scapula; depression of the scapula, abduction of the scapula,
N: Medial pectoral nerve (C8, T1) (some with fibers from the communicating branch of the lateral pectoral nerve C6, C7,C8,T1)
Subclavius
O: First rib at junction between rib and costal cartilage
I: Groove on inferior surface of middle one-third of clavicle
A: Anchors and stabilizes the sternoclavicular joint; depresses the clavicle, draws clavicle anteriorly, elevates first rib (assisting with inhalation)
N: nerve to subclavius (i.e. subclavian nerve) (C5,C6)
Serratus anterior
O: Lateral (i.e. external) surfaces of upper 8-9 ribs and deep fascia overlying the related intercostal spaces
I: Costal (i.e. anterior) surface of medial border of scapula
A: With the origin fixed: abduct/protraction of the scapula, upwardly rotate the scapula, depresses the scapula, holds the medial and inferior borders of the scapula against the rib cage.
With the scapula fixed: may act to elevate the thorax during forced inhalation
N: long thoracic nerve (C5, C6, C7)
Coracobrachialis
O: Apex of coracoid process
I: Linear roughening on medial midshaft of humerus;
A: Flexor of the arm at the glenohumeral joint; adducts the shoulder at the GH joint
N: Musculocutaneous nerve (C5, C6, C7)
Supraspinatus
O: Medial two-third of the supraspinous fossa of scapula and deep fascia that covers the muscle
I: Most superior facet on the greater tubercle of the humerus
A: Rotator cuff muscle, assists with maintaining glenohumeral head stability; abduction of shoulder at the glenohumeral joint
N: Suprascapular nerve (C4, C5, C6)
Infraspinatus
O: Medial two-third of the infraspinous fossa of scapula and deep fascia that covers the muscle
I: Middle facet on posterior surface of the greater tubercle of the humerus
A: Rotator cuff muscle, assists with maintaining glenohumeral head stability; lateral rotation of the arm at glenohumeral joint, adduction of the shoulder at GH joint
N: Suprascapular nerve (C5, C6)
Teres Minor
O: Upper two-thirds of lateral border of scapula
I: Inferior facet on the posterior surface of the greater tubercle of the humerus
A: Rotator cuff muscle, assists with maintaining glenohumeral head stability; lateral rotation of the
arm at the glenohumeral joint, adduction of the shoulder at the GH joint
N: Axillary nerve (C5, C6)
Subscapularis
O: Medial two-thirds of subscapular fossa
I: Lesser tubercle of the humerus
A: Rotator cuff muscle, assist with maintaining glenohumeral head stability; medial rotation of the shoulder at the glenohumeral joint
N: Upper and lower subscapular nerves (C5, C6,C7)
Biceps brachii
O: Long head-supraglenoid tubercle of the scapula
Short head-apex of coracoid process of the scapula
I: Radial tuberosity and fascia of the forearm via bicipital apponeurosis
A: Flexion of the forearm at the elbow joint and supinator of the forearm; accessory flexor of the
arm at the glenohumeral joint
N: Musculocutaneous nerve (C5, C6)
Brachialis
O: Distal half of anterior aspect of the humerus (medial and lateral surfaces) and adjacent intermuscular septae
I: Coronoid process and tuberosity of ulna
A: Flexion of the forearm at elbow in all positions
N: Musculocutaneous (C5, C6)
Triceps brachii
O: Long head - infraglenoid tubercle of scapula
Medial head - posterior surface of the distal half of humerus (distal to radial groove)
Lateral head - posterior surface of the proximal half of humerus (superior to radial groove)
I: Olecranon
A: All heads: extension of the forearm at elbow joint. Long head: can also extend and adduct the shoulder at the GH joint,
N: radial nerve (C6, C7, C8)
Anconeus
O: Lateral epicondyle of humerus
I: Olecranon process and proximal posterior surface of ulna
A: Accessory extension of the elbow joint; stabilize elbow joint; abducts ulna in pronation
N: Radial nerve (C6, C7, C8) (via branch to medial head of the triceps brachii)
Pronator Teres
O: Humeral head - medial epicondyle (i.e. site of common flexor tendon origin) and adjacent supraepicondylar ridge
Ulnar head - medial side of coronoid process
I: Roughening on lateral surface, midshaft, of the radius
A: pronation of the forearm (at the radio-ulnar joints)
N: median nerve (C6, C7)
Flexor carpi radialis
O: Medial epicondyle of humerus (i.e. site of common flexor tendon origin) from medial epicondyle of humerus
I: Base of 2nd and 3rd metacarpals
A: Flexion and abduction of the wrist; weak elbow flexion
N: Median (C6, C7)
Flexor carpi ulnaris
O: Humeral head - medial epicondyle of humerus (i.e. site of common flexor tendon origin) Ulnar head - olecranon and posterior proximal 2/3 of ulna
I: Pisiform bone, and then via pisohamate and pisometacarpal ligaments into the hook of hamate and base of 5th metacarpal bone
A: Flexion and adduction of the wrist joint; weak elbow flexion
N: Ulnar nerve (C7,C8)
Palmaris Longus
O: Medial epicondyle of humerus (i.e. site of common flexor tendon origin)
I: Palmar aponeurosis of hand; flexor retinaculum
A: flexion of wrist; resists shearing forces when gripping; weak flexion of the elbow
N: median nerve (C7, C8)
Flexor digitorum superficialis
O: Humero-ulnar head: medial epicondyle of humerus, adjacent margin of coronoid process, and interosseous membrane
Radial head: oblique line of radius
I: Four tendons, which attach to the palmar surfaces of the middle phalanges of the index, middle, ring, and little fingers
A: Flexion of proximal interphalangeal joints of digits 2-5; can also flex metacarpophalangeal joints of the same fingers and the wrist joint
N: Median nerve (C7, C8, T1)
Flexor digitorum profundus
O: Anterior and medial surfaces of the proximal ¾ of ulna and anterior medial half of interosseous membrane
I: Four tendons, which attach to the palmar surfaces of the distal phalanges of digits 2-5
A: Flexion of distal interphalangeal joints of the of digits 2-5; can also flex metacarpophalangeal joints of the same fingers and the wrist joint
N: Lateral half: anterior interosseous (median) C8,T1
Medial half: ulnar C8,T1
Flexor pollicis longus
O: Anterior surface of radius and radial half of interosseous membrane
I: Palmar surface of base of distal phalanx of thumb
A: Flexion of interphalangeal joint of the thumb; can also flex metacarpophalangeal and carpometacarpal joint of the thumb; assist to flex the wrist (weak)
N: Anterior interosseous nerve (median) (C8,T1)
Pronator quadratus
O: Linear ridge on distal anterior, medial surface of ulna
I: Distal anterior, lateral surface of radius
A: Pronation of the forearm
N: Anterior interosseous nerve (median) (C8, T1)
Brachioradialis
O: Proximal 2/3 of lateral supracondylar ridge of humerus and adjacent intermuscular septum
I: Styloid process of radius
A: Accessory flexion of elbow (humero-ulnar) joint when forearm is midpronated; assist with pronation and supination of the forearm with resistance (weak)
N: radial nerve (C5, C6, C7) before division into superficial and deep branches
Extensor carpi radialis longus
O: distal 1/3 part of lateral supracondylar ridge of humerus and adjacent intermuscular septum
I: Dorsal surface of base of 2nd metacarpal
A: Extension and abduction of the wrist; assists with elbow flexion (weak)
N: Rradial nerve (C6, C7) before division into superficial and deep branches
Extensor carpi radialis brevis
O: Lateral epicondyle of humerus and adjacent intermuscualr septum; part of common extensor tendon
I: Dorsal surface of base of 3rd metacarpal
A: Extension and abduction of the wrist; assists to flex the elbow (weak)
N: Deep branch of radial nerve (C7, C8) before penetrating supinator muscle
Extensor carpi ulnaris
O: Lateral epicondyle of humerus and posterior border of ulna; part of common extensor tendon from lateral epicondyle
I: Tubercle on the base of the medial side of the 5th metatcarpal
A: Extension and adduction of the wrist
N: Posterior interosseous nerve (radial nerve) (C7, C8)
Extensor digitorum
O: lateral epicondyle of humerus and adjunct intermuscular septum and deep fascia; part of common extensor tendon from the lateral epicondyle of humerus
I: Four tendons, which insert via extensor hood into the dorsal aspect of the bases of the middle and distal phalanges of digits 2-5
A: Extension of the index, middle, ring, and little finger (i.e. digits 2-5) MCPs and IPs; can also extend the wrists
N: Posterior interosseous nerve (radial) (C7, C8)
Extensor indicis proprius
O: Posterior surface of distal shaft of ulna (distal to extensor pollicis longus) and adjacent interosseous Membrane
I: Extensor hood of index finger
A: Extension of index (2nd) finger, may assist to extend the wrist (RC joint, weak)
N: Posterior interosseous nerve (radial) (C7, C8
Extensor digiti minimi
O: Lateral epicondyle of humerus and adjunct intermuscular septum together with extensor
digitorum
I: Extensor hood of the little finger
A: Extension of the little finger
N: Posterior interosseous nerve (radial) (C7, C8)
Supinator
O: Superficial part - lateral epicondyle of humerus, radial collateral and annular ligaments
Deep part – supinator crest of the ulna
I: Anterior and lateral surface of proximal one-third of radius superior to the anterior oblique line
A: Supination (of the radio-ulnar joints)
N: Deep branch of the radial nerve (C6, C7) (radial) before becoming the posterior interosseous n.
Abductor pollicis longus
O: Posterior surfaces of ulna and radius (distal to the attachments of supinator and anconeus), and
intervening interosseous membrane
I: Lateral side of base of 1st metacarpal
A: Abduction of the carpometacarpal joint of the thumb; accessory extension of the thumb; abduct the wrist (radiocarpal joint; weak)
N: Posterior interosseous nerve (radial) (C7, C8,)
Extensor pollicis longus
O: Posterior surfaces of ulna (distal to abductor pollicis longus), and the adjacent interosseous membrane
I: Dorsal surface of base of distal phalanx of thumb
A: Extension of the interphalangeal joint of the thumb; can also extend carpometacarpal and
metacarpophalangeal joints of the thumb; abduction of the wrist (radiocarpal joint; weak)
N: Posterior interosseous nerve (radial) (C7, C8)
Extensor pollicis brevis
O: Posterior surfaces of radius (distal to abductor pollicis longus), and the adjacent interosseous
membrane
I: Dorsal surface of base of proximal phalanx of thumb
A: Extension of the metacarpophalangeal joint of the thumb; can also extend the carpometacarpal
joint of the thumb; abduction of the wrist (radiocarpal joint)
N: Posterior interosseous nerve (radial) (C7, C8)
Abductor pollicis brevis
O: Tubercles of scaphoid and trapezium and adjacent flexor retinaculum
I: Base of proximal phalanx and extensor hood of the thumb
A: Abduction of the thumb at the metacarpophalangeal and carpometacarpal joints
N: Recurrent branch of median nerve (C8, T1)
Flexor pollicis brevis
O: Superficial head: Flexor retinaculum
Deep head: Trapezium tubercle, trapezoid, and capitate
I: Base of proximal phalanx of the thumb
A: Flexion of the thumb at the metacarpophalangeal and carpometacarpal joints; assists in opposition of thumb
N: Superficial head: Recurrent branch of median nerve (C8, T1)
Deep head: Ulnar C8,T1
Opponens pollicis
O: Tubercle of the trapezium and flexor retinaculum
I: Entire length of the 1st metacarpal on the radial surface
A: Opposition of thumb at carpometacarpal joint (bringing pads of the thumb and fifth finger together)
N: Recurrent branch of median nerve (C8, T1)
Abductor digiti minimi
O: Pisiform, the pisohamate ligament, and tendon of flexor carpi ulnaris
I: Base of proximal phalanx of little finger, ulnar surface
A: Abduction of the little finger at the metacarpophalangeal joint
N: Deep branch of ulnar nerve (C8, T1)
Flexor digiti minimi brevis
O: Hook of hamate and flexor retinaculum
I: Base of proximal phalanx of little finger palmar surface
A: Flexion of the little finger at the metacarpophalangeal joint; assist in opposition of the 5th finger toward the thumb
N: Deep branch of ulnar nerve (C8, T1)
Opponens digiti minimi
O: Hook of hamate and flexor retinaculum
I: Shaft of the 5th metacarpal, ulnar surface
A: Opposition of the 5th finger at the carpometacarpal joint
N: Deep branch of ulnar nerve (C8, T1)
Adductor pollicis
O: Transverse head – 3rd metacarpal bone
Oblique head – capitate and base of 2nd and 3rd metacarpals
I: Base of proximal phalanx and hood of the thumb
A: Adducts thumb (carpometacarpal and metacarpophalangeal joints)
N: Deep branch of ulnar nerve (C8, T1)
Dorsal interrossei
O: Adjacent sides of all metacarpal
I: Extensor hood (aponeurosis) and bases of proximal phalanges of index, middle and ring fingers
A: Abduction of index, middle, and ring fingers at the metacarpophalangeal joints; flex digits at 2nd, 3rd, 4th fingers at metacarpophalangeal joint and extend 2nd, 3rd, 4th fingers at interphalangeal joints
N: Deep branch of ulnar nerve (C8, T1)
Volar (Palmar) interossei
O: Sides of metacarpals 2, 4 and 5
I: Extensor hood of the thumb, index, ring and little fingers and proximal phalanx of the thumb
A: Adduction of the thumb, index, ring, and little fingers toward the 3rd finger at the metacarpophalangeal joints; assists to flex (thumb, 2nd, 4th, 5th, ) digits at metacarpophalangeal joint and assist to extend thumb, 2nd, 4th, and 5th fingers at interphalangeal joints
N: Deep branch of ulnar nerve (C8, T1)
Lumbricals
O: 1st and 2nd – lateral two tendons of flexor digitorum profundus
3rd and 4th - medial three tendons of flexor digitorum profundus
I: Extensor hoods of index, ring, middle, and little fingers
A: Flexion of the (2nd to 5th fingers) metacarpophalangeal joints and extension of the (2nd to 5th fingers) at the interphalangeal joints
N: Medial two by the deep branch of the ulnar nerve (C8, T1)
Lateral two by the digital branches of the median nerve (C8, T1)
