Muscle Attachments
Muscle Images
| Region | Muscle | Origin | Insertion | Action |
|---|---|---|---|---|
| Upper Limb - Vertebral Column | Trapezius | Down the midline, from the external occipital protuberance, the nuchal ligament, the medial part of the superior nuchal line, and the spinous processes of the vertebrae C7-T12 | At the shoulders, into the lateral third of the clavicle, the acromion process and into the spine of the scapula | Descending (superior) part elevates; ascending (inferior) part depresses; and middle part (or all parts together) retracts scapula; descending and ascending parts act together to rotate glenoid cavity superiorly |
| Upper Limb - Vertebral Column | Latissimus dorsi | Spinous processes of thoracic T6-T12, thoracolumbar fascia, iliac crest and inferior 3 or 4 ribs | Floor of intertubercular groove of the humerus | Pulls the forelimb dorsally and caudally |
| Upper Limb - Vertebral Column | Rhomboid major | Spinous processes of the T2 to T5 vertebrae | Medial border of the scapula, inferior to the insertion of rhomboid minor muscle | Retracts the scapula and rotates it to depress the glenoid cavity. It also fixes the scapula to the thoracic wall. |
| Upper Limb - Vertebral Column | Rhomboid minor | Nuchal ligaments and spinous processes of C7- to T1 vertebrae | Medial border of the scapula, superior to the insertion of rhomboid major muscle | Retracts the scapula and rotates it to depress the glenoid cavity. It also fixes the scapula to the thoracic wall. |
| Upper Limb - Vertebral Column | Levator scapulae | Posterior tubercles of transverse processes of C1 - C4 vertebrae | Superior part of medial border of scapula | Elevates scapula and tilts its glenoid cavity inferiorly by rotating scapula |
| Upper Limb - Thoracic Wall | Pectoralis major | Clavicular head: anterior surface of the medial half of the clavicle.; Sternocostal head: anterior surface of the sternum, the superior six costal cartilages | Intertubercular groove of the humerus | Clavicular head: flexes the humerus; Sternocostal head: extends the humerus; As a whole, adducts and medially rotates the humerus. It also draws the scapula anteriorly and inferiorly. |
| Upper Limb - Thoracic Wall | Pectoralis minor | 3rd to 5th ribs, near their costal cartilages | Medial border and superior surface of the coracoid process of the scapula | Stabilizes the scapula by drawing it inferiorly and anteriorly against the thoracic wall |
| Upper Limb - Thoracic Wall | Subclavius | First rib | Subclavian groove of clavicle | Depression of clavicle |
| Upper Limb - Thoracic Wall | Serratus anterior | Fleshy slips from the outer surface of upper 8 or 9 ribs | Costal aspect of medial margin of the scapula | Protract and stabilize scapula, assists in upward rotation |
| Shoulder | Deltoid | Lateral third of Clavicle, acromion, spine of the scapula | Deltoid tuberosity of humerus | Shoulder abduction, flexion and extension |
| Shoulder | Teres major | Posterior aspect of the inferior angle of the scapula | Medial lip of the intertubercular sulcus of the humerus | Internal rotation of the humerus |
| Shoulder - Rotator Cuff | Supraspinatus | Supraspinous fossa of scapula | Superior facet of greater tubercle of humerus | Abduction of arm and stabilizes humerus |
| Shoulder - Rotator Cuff | Infraspinatus | Infraspinous fossa of the scapula | Middle facet of greater tubercle of the humerus | Lateral rotation of arm & Adduction of arm and stabilizes humerus |
| Shoulder - Rotator Cuff | Teres minor | Lateral border of the scapula | Inferior facet of greater tubercle of the humerus | Laterally rotates and adducts the arm |
| Shoulder - Rotator Cuff | Subscapularis | Subscapular fossa | Lesser tubercle of humerus | Rotates medially humerus; stabilizes shoulder |
| Upper Arm - Anterior | Coracobrachialis | Coracoid process of scapula | Medial humerus | Adducts humerus |
| Upper Arm - Anterior | Biceps brachii | Short head: coracoid process of the scapula. Long head: supraglenoid tubercle | Radial tuberosity | Flexes elbow and supinates forearm |
| Upper Arm - Anterior | Brachialis | Anterior surface of the humerus, particularly the distal half of this bone | Coronoid process and the tuberosity of the ulna | Flexion at elbow joint |
| Upper Arm - Posterior | Triceps brachii | Long head: infraglenoid tubercle;medial head: arises distally from the groove of the radial nerve; from the dorsal (back) surface of the humerus; from the medial intermuscular septum; and its distal part also arises from the lateral intermuscular septum; lateral head: dorsal surface of the humerus, lateral and proximal to the groove of the radial nerve, from the greater tubercle down to the region of the lateral intermuscular septum | Olecranon process of ulna | Extends forearm, caput longum adducts shoulder |
| Upper Arm - Posterior | Anconeus | Lateral epicondyle of the humerus | Lateral surface of the olecranon process and the superior part of the posterior ulna | Partly blended in with the triceps, which it assists in extension of the forearm. Stabilises the elbow and abducts the ulna during pronation. |
| Forearm | Pronator teres | Humeral head: medial epicondyle of humerus (common flexor tendon); Ulnar head: coronoid process of the ulna | Radius | Pronation of forearm, flexes elbow |
| Forearm | Flexor carpi radialis | Medial epicondyle of humerus (common flexor tendon) | Bases of second and third metacarpal bones | Flexion and abduction at wrist |
| Forearm | Palmaris longus | Medial epicondyle of humerus (common flexor tendon) | Palmar aponeurosis | Wrist flexor |
| Forearm | Flexor carpi ulnaris | Medial epicondyle of the humerus (common flexor tendon) | Pisiform | Flexion and adduction of wrist |
| Forearm | Flexor digitorum superficialis | Medial epicondyle of the humerus (common flexor tendon), as well as parts of the radius and ulna. | Phalanges | Flexor of fingers (primarily at proximal interphalangeal joints) |
| Forearm | Pronator quadratus | Medial, anterior surface of the ulna | Lateral, anterior surface of the radius | Pronates the forearm |
| Forearm | Flexor digitorum profundus | Ulna | Distal phalanges | Flex hand, interphalangeal joints |
| Forearm | Flexor pollicis longus | The middle 2/4 of the volar [disambiguation needed] surface of the radius and the adjacent interosseus membrane. (Also occasionally a small origin slightly on the medial epicondyle of the ulna.) | The base of the distal phalanx of the thumb | Flexion of the thumb |
| Forearm | Brachioradialis | Lateral supracondylar ridge of the humerus | Distal radius (Radial styloid process) | Flexion of forearm |
| Forearm | Extensor carpi radialis longus | Lateral supracondylar ridge | 2nd metacarpal | Extensor at the wrist joint, abducts the hand at the wrist |
| Forearm | Extensor carpi radialis brevis | Humerus at the anterior of lateral epicondyle (common extensor tendon) | Base of the 3rd metacarpal | Extensor and abductor of the hand at the wrist joint |
| Forearm | Extensor digitorum | Lateral epicondyle (common extensor tendon) | 2nd through 5th phalanges | Extension of hand and fingers |
| Forearm | Extensor digiti minimi | The anterior portion of the lateral epicondyle of the humerus (common extensor tendon) | Extensor expansion, located at the base of the proximal phalanx of the finger on the dorsal side | Extends the little finger at all joints |
| Forearm | Extensor carpi ulnaris | Common extensor tendon (lateral epicondyle), ulna | 5th metacarpal | Extends and adducts the wrist |
| Forearm | Supinator | Lateral epicondyle of the humerus, supinator crest of ulna, radial collateral ligament, annular ligament | Lateral proximal radial shaft | Supinates forearm |
| Forearm | Extensor indicis | Ulna | Index finger (extensor hood) | Extends index finger, wrist |
| Forearm | Abductor pollicis longus | Ulna, radial styloid process | First metacarpal | Abduction, extension of thumb |
| Forearm | Extensor pollicis brevis | Radius | Thumb, proximal phalanx | Extension of thumb at metacarpophalangeal joint |
| Forearm | Extensor pollicis longus | Ulna | Thumb, distal phalanx | Extension of the thumb (metacarpophalangeal and interphalangeal) |
| Thenar | Opponens pollicis | Trapezium and transverse carpal ligament | Metacarpal bone of the thumb on its radial side | Opposition of the thumb |
| Thenar | Flexor pollicis brevis | Trapezoid, flexor retinaculum | Thumb, proximal phalanx | Flexion of thumb |
| Thenar | Abductor pollicis brevis | Transverse carpal ligament, the scaphoid and trapezium | Radial base of proximal phalanx of thumb and the thumb extensor [disambiguation needed]s | Abduction of thumb |
| Thenar | Adductor pollicis | Transverse head: anterior body of the third metacarpal; Oblique head: bases of the second and the third metacarpals and the adjacent trapezoid and capitate bones, | Medial side of the base of the proximal phalanx of the thumb and the ulnar sesamoid | Adducts the thumb at the carpometacarpal joint |
| Wrist | Palmaris brevis | Flexor retinaculum (medial), palmar aponeurosis | Palm | Wrinkle skin of palm |
| Hypothenar | Abductor digiti minimi | Pisiform | Base of the proximal phalanx of the 5th digit on the ulnar or medial side | Abduction of little finger |
| Hypothenar | Flexor digiti minimi brevis | Hamate bone | Little finger | Flexes little finger |
| Hypothenar | Opponens digiti minimi | Hook of hamate and flexor retinaculum | Medial border of 5th metacarpal | Draws 5th metacarpal anteriorly and rotates it, bringing little finger (5th digit) into opposition with thumb |
| Hand Intrinsic | Lumbrical | Flexor digitorum profundus | Extensor expansion | Flex metacarpophalangeal joints, extend interphalangeal joints |
| Hand Intrinsic | Dorsal interossei | Metacarpals | Proximal phalanges | Abduct finger |
| Hand Intrinsic | Palmar interossei | Metacarpals | Proximal phalange | Adduction |