Muscles of the Shoulder and Arm – Chart

Muscles of the Shoulder and Arm – Chart

Shoulder and arm        
 Muscle Origin  Insertion  Action  Notes 
Deltoid Lateral one-third of clavicle, acromion and spine of scapula Deltoid tuberosity of humerus Abduct the shoulder jointPosterior fibers extend and laterally rotate shoulder. Anterior fibers flex and medially rotate the shoulder. Origin is identical to the insertion of the trapezius.
Supraspinatus“Rotator cuff” Supraspinatus fossa of scapula Greater tubercle of humerus – superior facet Abducts the humerus; stabilizes head of humerus in glenoid cavity.Medially rotates humerus, draws it forward and down when arm is raised. Deep to trapezius-runs underneath the acromion.(only rotator cuff muscle that doesn’t rotate)
Infraspinatus“Rotator cuff” Infraspinous fossa of scapula Greater tubercle of humerus – middle facet Laterally rotate, adducts, extends the shoulder. Stabilizes head of humerus in glenoid cavity Attaches just posterior to the supraspinatus on the greater tubercle.Works with teres minor.
Teres Minor” Rotator cuff” Superior half of lateral border of scapula Greater tubercle of humerus, lowest facet Laterally rotates, adducts, extends the shoulder, stabilizes head of humerus in glenoid cavity  
Subscapularis“Rotator Cuff” Subscapular fossa of the scapula Lesser tubercle of the humerus Medially rotates shoulder joint, stabilizes head of humerus in glenoid cavity. Most often the culprit in “frozen shoulder”
Teres Major Inferior angle of scapula Medial lip of bicipital grove of humerus Adducts and medially rotates humerus and draws it back.  
Serratus Anterior Outer surface of ribs 1-8 Anterior medial border of scapula Abducts and upwardly rotates scapula, holds scapula against thoracic wall Lower fibers interdigitate with the external obliques. Weakness causes winged scapula. Tightness may cause “a stitch in the side”
Coracobracialis Corocoid process of scapula Middle of medial shaft of humerus Flexes and adducts the humerus  
Biceps Brachii Short head- Coracoid process of scapulaLong head- Supraglenoid tubercle of scapula Tuberosity of the radius and aponeurosis of biceps brachii Flexes elbow, supinates forearm, flexes shoulder joint  
Triceps Brachii Long head- Infraglenoid tubercle of scapulaLateral head- Posterior surface of proximal half of humerus

Medial head- Posterior surface of distal half of humerus

All heads- olecranon process of ulna Long head- Extends and adducts the shoulderAll heads- Extend the forearm (elbow)  
Subclavius First rib and cartilage Inferior, lateral aspect of clavicle Elevates first rib, stabilizes sternoclavicular joint, draws clavicle down Underneath the clavicle.
Brachialis Distal half of the anterior surface of humerus Tuberosity and coronoid process of ulna Flexes the elbow  
Bracioradialis Lateral supracondylar ridge of humerus Styloid process of radius Flexes forearm (handshake position)  
Pronator teres Medial epicondyle of humerus, coronoid process of ulna Middle of lateral surface of radius Pronates the forearmAssists in flexion of the elbow Resisted pronation
Forearm and hand        
Extensor digitorum Common extensor tendon from lateral epicondyle of humerus Dorsal surface of middle and distal phalanges 2-5 ( four fingers) Extends four fingers, assists in extension of the wrist  
Pronator quadratus        
Palmaris longus Medial epicondyle of humerus Palmar aponeurosis Flexion of hand and wrist Flex wrist against resistance to find tendon.May be absent in one or both sides in some people.
Flexor digitorum superficialis Medial epicondyle of humerus, coronoid process of ulna, proximal radius Four tendons into the middle phalanges of fingers 2-5, palmar surface Flexes the middle and proximal phalanges of fingers 2-5, flexion of the wrist and forearm. Median nerve and ulnar artery are under origin
Flexor carpi radialis Medial epicondyle of humerus Base of 2nd to base of 3rd metacarpal bone Flexes and abducts the wrist, pronation of the forearm and flexion of the elbow  
Flexor carpi ulnaris Medial epicondyle of humerus, medial olecranon and proximal posterior ulna Pisiform bone  Flexes and adducts the wrist and flexes the elbow  
Extensor carpi radialis longus Lateral supracondylar ridge of humerus Base of 2nd metacarpal bone dorsal side Extends and abducts the wrist, flexes the elbow  
Extensor carpi radialis brevis Lateral epicondyle of humerus Dorsal surface of base of 3rd metacarpal bone Extends and assists in abduction of the wrist  
Extensor carpi ulnaris Lateral epicondyle of humerus, posterior border of ulna Base of 5th metacarpal bone, ulnar side Extends and adducts the wrist Tendon runs through a groove between the head of the ulna and the styloid process of ulna
Flexor digitorum profundus Anterior and medial surfaces of proximal ¾ of ulna Four tendons into bases of distal phalanges on anterior surface Flexes distal interphalangeal joints of four fingers, flexes proximal interphalageal and metacarpopphalangeal joints  
Flexor pollicus longus Anterior surface of radius, deep to flexors Distal phalange of thumb Flexes thumb  
Supinator Lateral epicondyle of humerus, posterior ulna Proximal anterior shaft of humerus Supinates forearm  
Extensor pollicus longus and brevis Posterior surface of radius and ulna, deep to extensors Brevis –proximal phalange of thumbLongus- distal phalange of thumb Extends the thumb  
Opponens pollicis Palmar retinaculum, trapezium 1st metacarpal anterior surface Opposition of thumb to each digit.Rotates 1st metacarpal so the thumbnail faces the ceiling when the hand is resting palm up.  

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