Anatomy and Physiology I Muscles that Move the Arm, Forearm, Hand and Fingers Instructor: Mary Holman Review: Muscles that Move the Pectoral Girdle Anterior Thoracic Muscles • Pectoralis minor • Serratus anterior Posterior Thoracic Muscles • Trapezius * • Levator scapulae • Rhomboid major * • Rhomboid minor * = know origin & insertion Fig. 9.28 Pectoralis minor Anterior Origin: Three upper ribs (can vary) Insertion: Coracoid process of scapula Action: Depresses and pulls scapula forward, rotates it downward Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Fig. 9.28 Serratus anterior Origin: Superior 8 or 9 ribs Insertion: Ventral surface of scapula Action: Pulls scapula anteriorly and downward Anterior Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Posterior Anterior Trapezius * Origin: Occipital bone & spines of 7th cervical and all thoracic vertebrae Insertion: Clavicle, spine, and acromion process of scapula Action: Rotates scapula can raise, pull medially, pull upward or depress scapula Fig. 9.28 Fig. 9.27b Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Fig. 9.29a Levator scapulae Posterior Origin: Transverse Spine of scapula processes of superior 4 or 5 cervical vertebrae Insertion: Medial border of scapula Action: Elevates scapula and rotates it downward Fig. 9.27d Posterior Rhomboideus major * Fig. 9.27a Origin: Spines of upper thoracic vertebrae Insertion: Medial margin of scapula Action: Adducts, elevates and rotates scapula Fig. 9.27d Posterior Rhomboideus minor Fig. 9.27a Origin: Spines of lower cervical vertebrae Insertion: Medial margin of scapula Action: Adducts, and elevates scapula Origins of Muscles that Move the Humerus (Upper Arm) 2 Originate on Axial Skeleton • Pectoralis major * • Latissimus dorsi 7 Originate on Scapula • Deltoid * • Suprascapularis • Infrascapularis • Teres minor • Subscapularis • Teres major • Coracobrachialis Rotator cuff Muscles Muscles that Move the Humerus (Arm) 2 Flexors * Pectoralis major Coracobrachialis 2 Extensors * Latissimus dorsi Teres major * The muscles that flex and extend the humerus also act as adductors 2 Abductors Deltoid Supraspinatus 3 Rotators Infraspinatus Teres minor Subscapularis Fig. 9.28 Pectoralis major * Origin: Clavicle, sternum, and costal cartilages of upper ribs Insertion: Intertubercular groove of humerus Action: Flexes, adducts and rotates arm medially Anterior Fig. 9.31a Fig. 9.31d Coracobrachialis Origin: Coracoid process of the scapula Insertion: Shaft of humerus medial side Action: Flexes and adducts the arm Anterior Latissimus dorsi Fig. 9.27a Posterior Fig. 9.27d Origin: spines of vertebrae, iliac crest and lower ribs Insertion: Intertubercular groove humerus Action:Extends, adducts and rotates arm medially Teres major Fig. 9.29b Posterior Origin: Lateral Fig. 9.29a Posterior border of scapula Insertion: Intertubercular groove of humerus Action: Extends, adducts and rotates arm medially Fig. 9.31a Deltoid * Anterior Fig. 9.29a Posterior Origin: Spine and acromion of scapula, & clavicle Insertion: Deltoid tuberosity of humerus Action: Abducts, flexes, and extends arm. Fig. 9.29c Supraspinatus Origin: Posterior surface of scapula above spine Insertion: Greater tubercle of humerus Action: Abducts arm Posterior Fig. 9.29b Infraspinatus Origin: Posterior surface of scapula below spine Insertion: Greater tubercle of humerus Action: Rotates arm laterally Posterior Fig. 9.29c Fig. 9.29a Teres minor Origin: Lateral border of scapula Insertion: Greater tubercle of humerus Action: Rotates arm laterally Posterior Fig. 9.31a Fig. 9.31c Subscapularis Origin: Anterior surface of scapula Insertion: Lesser tubercle of humerus Action: Rotates arm medially Anterior Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Rotator Cuff Muscles S I T S Supraspinatus Infraspinatus Teres minor Subscapularis Assist the joint capsule, coracohumeral ligament, glenohumeral ligament and transverse ligament in stabilizing the shoulder joint Rotator Cuff S I A T B S Anterior From: Anatomy & Physiology: Seeley, Stephens and Tate 6th Ed. Fig. 9.30 Pectoralis major Serratus anterior Coracobrachialis Deltoid Teres major Latissimus dorsi Humerus Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Muscles that Move the Forearm • Biceps brachii * • Brachialis * • Brachioradialis • Triceps brachii * • Supinator • Pronator teres • Pronator quadratus Actions of the Muscles that Move the Forearm 3 Flexors Biceps brachii Brachialis Brachioradialis “3” Extensors Triceps brachii 3 Rotators Supinator Pronator teres Pronator quadratus Fig. 9.31b Anterior Biceps brachii * Short head Long head Origin: Short head - Coracoid process Long head - Tubercle above glenoid cavity of scapula Insertion: Radial tuberosity and aponeurosis Action: Flexes forearm at elbow and rotates arm laterally (supinates) Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Fig. 9.31a Fig. 9.31d Brachialis * Origin: Anterior shaft of humerus Insertion: Coronoid process of the ulna Action: Flexes forearm at the elbow Anterior Fig. 9.32a Fig. 9.32b Brachioradialis Origin: Lateral border of the distal end of the humerus Insertion: Superior to styloid process of the radius Action: Flexes forearm at elbow Anterior Fig. 9.29d Posterior Triceps brachii * Origin: Tubercle below glenoid cavity and lateral and medial surfaces of the humerus Insertion: Olecranon process of the ulna Action: Extends elbow Posterior Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Fig. 9.32a Anterior Supinator Origin: Lateral epicondyle of humerus and ridge near the radial notch of ulna Insertion: Lateral surface of proximal third of radius Action: Rotates forearm laterally (supinates hand) From: Anatomy & Physiology: Seeley, Stephens and Tate 6th Ed. Fig. 9.32c Pronator teres Origin: Medial epicondyle of humerus and coronoid process of ulna Insertion: Lateral surface of radius Action: Rotates forearm medially (pronates hand) Anterior Fig. 9.32c Pronator quadratus Origin: Anterior distal end of ulna Insertion: Anterior distal end of radius I O Action: Rotates forearm medially (pronates hand) Anterior Fig. 9.30 Short head of biceps brachii Long head of biceps brachii Humerus Triceps brachii Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Muscles that Move the Hand • Flexor carpi radialis • Palmaris longus • Flexor carpi ulnaris • Extensor carpi radialis longus • Extensor carpi radialis brevis • Extensor carpi ulnaris Actions of the Muscles that Move the Hand 3 Flexors Flexor carpi radialis Palmaris longus Flexor carpi ulnaris 3 Extensors Extensor carpi radialis longus Extensor carpi radialis brevis Extensor carpi ulnaris Fig. 9.32a Fig. 9.32d Flexor carpi radialis Origin: Medial epicondyle of humerus Insertion: Base of 2nd and 3rd metacarpals Action: Flexes wrist and abducts hand Anterior Fig. 9.32a Palmaris longus Origin: Medial epicondyle of humerus Insertion: Fascia of palm Action: Flexes wrist Anterior Fig. 9.32a Ant Fig. 9.32b Ant Flexor carpi ulnaris Post 9.33a Origin: Medial epicondyle of humerus and olecranon process of the ulna Insertion: Carpal & metacarpal bones Action: Flexes wrist and adducts hand Fig. 9.33a Fig. 9.33c Extensor carpi ulnaris Origin: Lateral epicondyle of humerus Insertion: Carpal and metacarpal bones Action: Extends and adducts hand Posterior Fig. 9.33a Fig. 9.33b Extensor carpi radialis longus brevis Origin: longus - distal end of humerus brevis - lateral epicondyle of humerus Insertion: longus - base of 2nd metacarpal brevis - base of 2nd & 3rd metacarpal Action: Extends wrist & abducts hand Posterior Muscles that Move the Fingers • Flexor digitorum superficialis • Flexor digitorum profundus • Extensor digitorum Actions of the Muscles that Move the Fingers 2 Flexors Flexor digitorum superficialis Flexor digitorum profundus 1 Extensor Extensor digitorum Fig. 9.32a Fig. 9.32e Flexor digitorum superficialis Origin: Medial epicondyle of humerus, olecranon process of ulna, and the radius Insertion: Tendons of the fingers Action: Flexes the fingers and wrist Anterior Anterior Flexor digitorum profundus Origin: Anterior surface of ulna Insertion: Bases of distal phalanges 2 through 5 Action: Flexes the distal joints of the fingers From: Anatomy & Physiology: Seeley, Stephens and Tate 6th Ed. Fig. 9.33a Fig. 9.33c Extensor digitorum Origin: Lateral epicondyle of the humerus Insertion: Posterior surfaces of phalanges in fingers 2 through 5 Action: Extends fingers and wrist Posterior Fig. 9.34b Abductor pollicis longus m. Extensor digitorum m. Flexor pollicis longus m. Extensor carpi ulnaris m. Radius Extensor pollicis longus m. Extensor carpi radialis brevis m. p p Extensor carpi radialis longus m. p Pronator teres m. Ulna Flexor digitorum profundus m. Ulnar n. Brachioradialis m. Ulnar a. Radial n. Flexor carpi ulnaris m. Radial a. Median n. Flexor carpi radialis m. Anterior Flexor digitorum superficialis m. Palmaris longus m. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Flexor retinaculum Extensor retinaculum