-
Deltoid
- Origin: Lateral 1/3 of clavical, acromion, and spine of scapula
- Insertion: Deltoid tuberosity
- Innervation: Axillary from brachial plexus
- Actions: All fibers - Adduct shoulder (glenohumeral joint); Ant. Fibers - Flex, medially rotate, horizontally adduct shoulder (glenohumeral joint); Post. Fibers - Extend, laterally rotate, horizontally abduct shoulder (glenohumeral joint)
-
Trapezius
- Origin: External occipital protuberance, medial portion of superior nuchal line of occiput, ligamentum nuchae, and spinous processes of C7-T12
- Insertion: Lateral 1/3 of clavicle, acromion, spine of scapula
- Innervation: Spinal accesory, cervical plexus
- Actions: Upper Fibers - Bilateral extension of head and neck, unilateral flexion of head and neck to same side, rotation of head and neck to opposite side, elevate & upwardly rotate scapula (scapulothoracic joint); Middle Fibers - Adduct & stabilize scapula (scapulothoracic joint); Lower Fibers - Depress & upwardly rotate scapula (scapulothoracic joint)
-
Latissimus Dorsi
- Origin: Spinous processes of last 6 thoracic vertebrae, last 3-4 ribs, thoracolumbar aponeurosis, and posterior iliac crest
- Insertion: Crest of lesser tubercle of humerus
- Innervation: Brachial plexus
- Actions: Extend, adduct, medially rotate shoulder (glenohumeral joint)
-
Teres Major
- Origin: Lateral side of inferior angle and lower half of lateral border of scapula
- Insertion: Crest of lesser tubercle of humerus
- Innervation: Lower subscapular
- Actions: Extend, adduct, medially rotate shoulder (glenohumeral joint)
-
Supraspinatus
- Origin: Supraspinatus fossa of scapula
- Insertion: Greater tubercle of humerus
- Innervation: Suprascapular n.
- Actions: Abduct shoulder (glenohumeral joint), stabilizes head of humerus in glenoid cavity
-
Infraspinatus
- Origin: Infraspinous fossa of scapula
- Insertion: Greater tubercle of humerus
- Innervation: Suprascapular from brachial plexus
- Actions: Laterally rotate, adduct, extend, horizontally abduct shoulder (glenohumeral joint); stabilizes head of humerus in glenoid cavity
-
Teres Minor
- Origin: Superior half of lateral border of scapula
- Insertion: Greater tubercle of humerus
- Innervation: Axillary n.
- Actions: Laterally rotate, adduct, extend, horizontally abduct shoulder (glenohumeral joint); stabilizes head of humerus in glenoid cavity
-
Subscapularis
- Origin: Subscapular fossa of scapula
- Insertion: Lesser tubercle of humerus
- Innervation: Subscapular n.
- Actions: Medially rotates shoulder (glenohumeral joint), stabilizes head of humerus in glenoid cavity
-
Rhomboid Major
- Origin: Spinous processes of T2-5
- Insertion: Medial border of scapula between spine of scapula and inferior angle
- Innervation: Dorsal scapular from brachial plexus
- Actions: Adducts, elevates, downwardly rotates scapula (scapulothoracic joint)
-
Rhomboid Minor
- Origin: Spinous processes of C7-T1
- Insertion: Medial border of scapula between spine of scapula and inferior angle
- Innervation: Dorsal scapular from brachial plexus
- Actions: Adduct, elevate, downwardly rotate scapula (scapulothoracic joint)
-
Levator Scapula
- Origin: Transverse processes of 1st-4th cervical vertebrae
- Insertion: Medial border and superior angle of scapula
- Innervation: Dorscal Scapular n., Cervical nn.
- Actions: Elevates, downwardly rotates scapula; flexis head and neck laterally, rotates head and neck to same side
-
Serratus Anterior
- Origin: Surfaces of upper eight or nine ribs
- Insertion: Anterior surface of medial border of scapula
- Innervation: Long thoracic n. from brachial plexus
- Actions: With origin fixed - Abducts, depresses scapula at scapulothoracic joint, holds medial border of scapula against the rib cage; With scapula stabilized - may act in forced inhalation
-
Pectoralis Major - Upper Fibers
- Origin: Medial half of clavicle
- Insertion: Crest of greater tubercle of humerus
- Innervation: Anterior thoracic n. from brachial plexus
- Actions: Adduct and medially rotate the shoulder at the glenohumeral joint, may assist in elevating the thorax in forced inhalation (arm fixed), flex and horizontally adduct the shoulder
-
Pectoralis Major - Lower Fibers
- Origin: Sternum, cartilage of ribs 1-6
- Insertion: Crest of greater tubercle of humerus
- Innervation: Anterior thoracic n. from brachial plexus
- Actions: Adduct; medially rotate and extend the shoulder at the glenohumeral joint; may assist in elevating thorax in forced inhalation (arm fixed)
-
Pectoralis Minor
- Origin: 3rd-5th ribs
- Insertion: Coracoid process of scapula
- Innervation: Anterior thoracic n. from brachial plexus
- Actions: Depresses, abducts, anteriorly tilts scapula at scapulothoracic joint; assists in forced inhalation (scapula fixed)
-
Subclavius
- Origin: 1st rib and cartilage
- Insertion: Inferior, lateral aspect of clavicle
- Innervation: 5th and 6th cervical nn.
- Actions: Draws clavicle inferiorly and anteriorly, elevates 1st rib, stabilizes sternoclavicular joint
-
Biceps Brachii
- Origin: Short head - Coracoid process of scapula; Long head - Supraglenoid tubercle of scapula
- Insertion: Tuberosity of the radius and aponeurosis of the biceps brachii Innervation: Musculocutaneus n.
- Actions: Flexes the elbow at the humeroulnar joint, supinates the forearm at the radioulnar joint, flexes the shoulder at the glenohumeral joint
-
Triceps Brachii
- Origin: Long head - Infraglenoid tubercle of scapula, Lateral head - Posterior surface of proximal half of humerus, Medial head - Posterior surface of distal 1/2 of humerus
- Insertion: Olecranon process of ulna
- Innervation: Radial n.
- Actions: Extend the elbow at the humeroulnar joint; long head also extends and adducts the shoulder at the glenohumeral joint
-
Coracobrachialis
- Origin: Coracoid process of scapula
- Insertion: Medial surface of mid-humeral shaft
- Innervation: Musculocutaneus n.
- Actions: Flexes and adducts the shoulder at the glenohumeral joint
-
Brachialis
- Origin: Distal 1/2 of anterior surface of humerus
- Insertion: Tuberosity and coronoid process of ulna
- Innervation: Musculocutaneus n.
- Actions: Flexes the elbow at the humeroulnar joint
-
Brachioradialis
- Origin: Lateral supracondylar ridge of humerus
- Insertion: Styloid process of radius
- Innervation: Musculocutaneus and radial nn.
- Actions: Flexes the elbow at the humeroulnar joint, assists in pronation and supenation of the forearm when movements are resisted
-
Extensor Carpi Radialis Longus
- Origin: Lateral supracondylar ridge of humerus
- Insertion: Base of 2nd metacarpal
- Innervation: Radial n.
- Actions: Extend and abduct the wrist at the radiocarpal joint, assist in flexion of the elbow at the humeroulnar joint
-
Extensor Carpi Radialis Brevis
- Origin: Lateral supracondylar ridge of humerus
- Insertion: Base of 3rd metacarpal
- Innervation: Radial n.
- Actions: Extend and abduct the wrist at the radiocarpal joint, assist in flexion of the elbow at the humeroulnar joint
-
Extensor Digitorum
- Origin: Common extensor tendon from lateral epicondyle of humerus
- Insertion: Middle and distal phalanges of 2nd-5th fingers
- Innervation: Radial n.
- Actions: Extend 2nd-5th fingers at metacarpophalangeal and interphalangeal joints, assists in extension of wrist at radiocarpal joint
-
Extensor Carpi Ulnaris
- Origin: Common extensor tendon from lateral epicondyle of humerus
- Insertion: Base of 5th metacarpal
- Innervation: Radial n.
- Actions: Extend and adduct the wrist at the radiocarpal joint
-
Flexor Carpi Radialis
- Origin: Common flexor tendon from medial epicondyle
- Insertion: Base of 2nd and 3rd metacarpals
- Innervation: Median n.
- Actions: Flexes and abducts the wrist at the radiocarpal joint, flexes the elbow at the humeroulnar joint
-
Palmaris Longus
- Origin: Common flexor tendon from medial epicondyle
- Insertion: Flexor retinaculum and palmar aponeurosis
- Innervation: Median n.
- Actions: Tenses palmar fascia, flexes the wrist at the radiocarpal joint, flexes the elbow at the humeroulnar joint
-
Flexor Carpi Ulnaris
- Origin: Common flexor tendon from medial epicondyle
- Insertion: Pisiform
- Innervation: Ulnar n.
- Actions: Flexes and adducts the wrist at the radiocarpal joint, may flex the elbow at the humeroulnar joint
-
Flexor Digitorum Superficialis
- Origin: Common flexor tendon from medial epicondyle of humerus, ulnar collateral ligament, coronoid process of radius
- Insertion: By 4 tendons into sides of middle phalanges of 2nd-5th fingers
- Innervation: Ulnar n.
- Actions: Flexes 2nd-5th fingers at metacarpophalangeal and proximal interphalangeal joints, flexes the wrist at the radiocarpal joint
-
Flexor Digitorum Profundus
- Origin: Anterior and medial surfaces of proximal 3/4 of ulna
- Insertion: By 4 tendons into bases of distal phalanges, palmar surface
- Innervation: Ulnar n.
- Actions: Flexes the 2nd-5th fingers at the metacarpophalangeal and distal interphalangeal joints, may flex wrist at radiocarpal joint
-
Pronator Teres
- Origin: Medial epicondyle of humerus, common flexor tendon, and coronoid process of ulna
- Insertion: Middle of lateral surface of radius
- Innervation: Median n.
- Actions: Pronates the forearm at the radioulnar joint, assists in flexion of elbow at the humeroulnar joint
-
Supinator
- Origin: Lateral epicondyle of humerus, radial collateral ligament, and annular ligament
- Insertion: Lateral surface of proximal shaft of radius
- Innervation: Radial n.
- Actions: Supinates the forearm at the radioulnar joint
-
Opponens Pollicis
- Origin: Flexor retinaculum and tubercle of trapezium
- Insertion: Entire length of 1st metacarpal bone, radial side
- Innervation: Median n.
- Actions: Opposition of the thumb at the carpometacarpal joint (bringing pads of thumb and last finger together)
-
1st Dorsal Interossei
- Origin: Ulnar surface of 1st metacarpal, radial surface of 2nd metacarpal Insertion: Proximal phalange on radial side of index finger
- Innervation: Ulnar n.
- Actions: Abducts and assists in flexion of index finger at metacarpophalangeal joint, assists in extension of index finger at interphalangeal joints
-
Adductor Pollicis
- Origin: Capitate, 2nd and 3rd metacarpals
- Insertion: Base of proximal phalange of thumb
- Innervation: Ulnar n.
- Actions: Adduct the thumb at the carpometacarpal joint, adduct and assist flexion of the thumb at the metacarpophalangeal joint
-
Extensor Pollicis Longus
- Origin: Posterior surface of radius and ulna
- Insertion: Distal phalange of thumb
- Innervation: Radial n.
- Actions: Extend the thumb at the interphalangeal joint, assist in extending the thumb at the metacarpophalangeal and carpometacarpal joints
-
Flexor Pollicis Longus
- Origin: Anterior surface of radius, deep to flexors
- Insertion: Distal phalange of thumb
- Innervation: Median n.
- Actions: Flexes the thumb at the interphalangeal joint, assists in flexing the thumb at the metacarpophalangeal and carpometacarpal joints
-
Abductor Pollicis Longus
- Origin: Posterior surface of radius and ulna, deep to extensors
- Insertion: Base of first metacarpal
- Innervation: Radial n.
- Actions: Abducts and extends the thumb at the carpometacarpal joint
-
Extensor Digiti Minimi
- Origin: Lateral epicondyle of humerus at common extensor origin
- Insertion: Extensor expansion of 5th finger
- Innervation: Radial n.
- Actions: Extends rth finger primarily at metacarpophalangeal joint, secondarily at interphalangeal joints
-
Extensor Indicis
- Origin: Posterior surface of distal 1/3 of ulna and interosseus membrane Insertion: Extensor expansion fo 2nd finger
- Innervation: Radial n.
- Actions: Extends 2nd finger, helps extend wrist at radiocarpal joint
-
Pronator Quadratus
- Origin: Distal quarter of anterior surface of ulna
- Insertion: Distal quarter of anterior surface of radius
- Innervation: Anterior interosseous n. from median n.
- Actions: Pronates forearm, deep fibers bind radius and ulna together
-
Anconeus
- Origin: Lateral epicondyle of humerus
- Insertion: Lateral surface of olecranon and superior part of posterior surface of ulna
- Innervation: Radial n.
- Actions: Assists triceps in extending forearm, stabilizes elbow joint, may abduct ulna during pronation
-
Abductor Pollicis Brevis
- Origin: Flexor retinaculum and tubercles of scaphoid and trapezium
- Insertion: Lateral side of base of proximal phalanx of thumb
- Innervation: Recurrent branch of median n.
- Actions: Abducts thumb, helps oppose it
-
Flexor Pollicis Brevis
- Origin: Flexor retinaculum and tubercles of scaphoid and trapezium
- Insertion: Lateral side of base of proximal phalanx of thumb
- Innervation: Recurrent branch of median n. (superficial head) and deep branch of ulnar n. (deep head)
- Actions: Flexes thumb
-
Flexor Digiti Minimi
- Origin: Hook of hamate and flexor retinaculum
- Insertion: Medial border of 5th metacarpal
- Innervation: Deep branch of ulnar n.
- Actions: Flexes proximal phalanx of 5th finger
-
Opponens Digiti Minimi
- Origin: Hook of hamate and flexor retinaculum
- Insertion: Medial border of 5th metacarpal
- Innervation: Deep branch of ulnar n.
- Actions: Draws 5th metacarpal anteriorly and rotates it, bringing 5th finger into opposition with thumb
-
Abductor Digiti Minimi
- Origin: Pisiform
- Insertion: Medial side of base of proximal phalanx of 5th finger
- Innervation: Deep branch of ulnar n.
- Actions: Abducts 5th finger, assists in flexion of its proximal phalanx
-
Dorsal Interossei
- Origin: Adjacent sides of 2 metacarpals as bipennate mm.
- Insertion: Bases of proximal phalanges, extensor expansions of 2nd-4th fingers
- Innervation: Deep branch of ulnar n.
- Actions: abduct 2nd-4th fingers from axial line, act with lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints
-
Palmar Interossei
- Origin: Palmar surfaces of 2nd, 4th and 5th metacarpals as unipennate mm.
- Insertion: Bases of proximal phalangs; extensor expansions of 2nd, 4th and 5th fingers
- Innervation: Deep branch of Ulnar n.
- Actions: Adduct 2nd, 4th and 5th fingers toward axial line; assist lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints
-
Lumbricals
- Origin: Tendons of flexor digitorum profundus; 1 and 2 as unipennate from lat. 2 tendons, 3 and 4 as bipennate from medial 3 tendons
- Insertion: Lateral sides of extensor expansions of 2nd-5th fingers
- Innervation: Median n.
- Actions: Flex metacarpophalangeal joints; extend interphalangeal joints of 2nd-5th fingers
|
|
