Muscles Forearm Flashcards
Superficial muscles of the volar forearm
Pronator teres, Flexor carpi radialis, Palmaris longus, Flexor carpi ulnaris
Origin of pronator teres
Humeral head - medial epicondyle of humerus
Ulnar head - coronoid process
Insertion of pronator teres
Lateral radius
distal to supinator insertion
Innervation of pronator teres
Median nerve (C6-C7)
Action of pronator teres
Elbow - weak flexor
Forearm - pronation
Origin of flexor carpi radialis
Medial epicondyle of humerus
Insertion of flexor carpi radialis
Base of 2nd metacarpal
Innervation of flexor carpi radialis
Median Nerve (C6-C7)
Action of flexor carpi radialis
Wrist - flexion, radial deviation of hand
*radial deviation = abduction
Origin of palmaris longus
Medial epicondyle of humerus
Insertion of palmaris longus
Palmar aponeurosis
Innervation of palmaris longus
Median nerve (C7-C8)
Action of palmaris longus
Elbow - weak flexor
Wrist - flexion tightens aponeurosis
Origin of flexor carpi ulnaris
Humeral head - medial epicondyle of humerus
Ulnar head - olecranon
Insertion of flexor carpi ulnaris
Pisiform, Hook of hammate, base of 5th metacarpal
Innervation of flexor carpi ulnaris
Ulnar nerve (C7-T1)
Action of flexor carpi ulnaris
Wrist - flexion; ulnar deviation
Intermediate muscles of the volar forearm
Flexor digitorum superficialis
Origin of flexor digitorum superficialis
Humeroulnar head - medial epicondyle of humerus
Radial head - Upper half of anterior surface of radius
Insertion of flexor digitorum superficialis
Sides of middle phalanges of the 2nd to 5th digits
Innervation of flexor digitorum superficialis
Median nerve (C8-T1)
Action of flexor digitorum superficialis
Elbow - weak flexor
Wrist, MCP, PIP of 2nd to 5th digits - flexion
Deep muscles of volar forearm
Flexor digitorum profundus, Flexor Pollicis Longus, Pronator Quadratus
Origin of flexor digitorum profundus
- Proximal 2/3 of anterior surface of ulna
- Interosseus membrane
Insertion of flexor digitorum profundus
Distal phalange of 2nd to 5th digits (palmar surface)
Innervation of flexor digitorum profundus
Anterior interosseus branch of Median nerve (C8-T1) Ulnar Nerve (C8-T1)
Action of flexor digitorum profundus
Wrist, MCP, PIP, DIP of 2nd - 5th digits : flexion
Origin of Flexor pollicis longus
- Midanterior surface of radius
- Interosseus membrane
Insertion of flexor pollicis longus
Distal phalanx of thumb (palmar surface)
Innervation of flexor pollicis longus
Anterior interosseus branch of Median nerve (C8-T1)
Action of flexor pollicis longus
Wrist - flexion, radial deviation of the hand
Carpometacarpal of thumb - flexion
MCP, IP of thumb - flexion
Origin of pronator quadratus
Distal quarter of ulna (anterior surface)
Insertion of pronator quadratus
Distal quarter of radius (anterior surface)
Innervation of pronator quadratus
Anterior interosseus branch of Median nerve (C8-T1)
Action of pronator quadratus
Hand - pronation
Distal radioulnar joint - stabilization
Layers of the muscles of the volar forearm
Superficial, intermediate, deep
Origin of Brachioradialis
- Distal surface of humerus
- Lateral intermuscular septum
Insertion of brachioradialis
Styloid process of radius
Innervation of brachioradialis
Radial nerve (C5-C6)
Action of brachioradialis
- Weak elbow flexor (in semipronation)
- Semipronation of elbow
Origin of extensor carpi radialis longus
- Lateral supracondylar ridge
- Lateral intermuscular septum
Insertion of extensor carpi radialis longus
Base of 2nd metacarpal
Innervation of extensor carpi radialis longus
Radial nerve (C6-C7)
Action of extensor carpi radialis longus
Elbow - weak flexor
Wrist - radial deviation; extension
Origin of extensor carpi radialis brevis
Lateral epicondyle of humerus
Insertion of extensor carpi radialis brevis
Base of 3rd metacarpal
Innervation of extensor carpi radialis brevis
Radial nerve (C7-C8)
Action of extensor carpi radialis brevis
Elbow - weak flexor
Wrist - extension; radial deviation
Origin of extensor digiti minimi
Lateral epicondyle of humerus
Origin of extensor digitorum
Lateral epicondyle of humerus
Insertion of extensor digitorum
Dorsal digital expansion of digits 2-5
Innervation of extensor digitorum
Posterior interosseus branch of Radial nerve (C7-C8)
Action of extensor digitorum
Wrist - extension
MCP, PIP, DIP of 2nd to 5th digits - extension and abduction of fingers
Origin of extensor digiti minimi
Lateral epicondyle of humerus
Insertion of extensor digiti minimi
Dorsal digital expansion of 5th digit
Innervation of extensor digiti minimi
Posterior interosseus branch of Radial Nerve (C7-C8)
Action of extensor digiti minimi
Wrist - extension, ulnar deviation
MCP, PIP, DIP of 5th digit - extension and abduction of 5th digit
Origin of Extensor carpi ulnaris
- Lateral epicondyle of humerus
- Dorsal surface of ulnar head
Insertion of extensor carpi ulnaris
Base of 5th metacarpal
Innervation of extensor carpi ulnaris
Posterior interosseus branch of Radial nerve (C7-C8)
Action of extensor carpi ulnaris
Wrist - extension, ulnar deviation
Origin of supinator
Olecranon process of ulna, lateral epicondyle of humerus, annular ligament, radial collateral ligament
Insertion of supinator
Radius
in between the radial tuberosity and the insertion of the pronator teres
Innervation of supinator
Posterior interosseus branch of Radial nerve (C6-C7)
Action of supinator
Forearm - supination
Origin of abductor pollicis longus
- Posterior surface of radius and ulna
- Interosseus membrane
Insertion of abductor pollicis longus
Base of 1st metacarpal
Innervation of abductor pollicis longus
Posterior interosseus branch of Radial nerve (C7-C8)
Action of abductor pollicis longus
Wrist - radial deviation
CMC of thumb - abduction of thumb
Origin of extensor pollicis brevis
- Posterior surface of radius
- Interosseus membrane
Insertion of extensor pollicis brevis
Base of proximal phalanx of thumb
Innervation of extensor pollicis brevis
Posterior interosseus branch of Radial nerve (C7-C8)
Action of extensor pollicis brevis
Wrist - radial deviation
CMC, MCP of thumb - extension of thumb
Origin of extensor pollicis longus
- Posterior surface of ulna
- Interosseus membrane
Insertion of extensor pollicis longus
Base of distal phalanx of thumb
Innervation of extensor pollicis longus
Posterior interosseus branch of Radial nerve (C7-C8)
Action of extensor pollicis longus
Wrist - extension and radial deviation
CMC of thumb - adduction
MCP, IP of thumb - extension
Origin of extensor indicis
- Posterior surface of ulna
- Interosseus membrane
Insertion of extensor indicis
Dorsal digital expansion of 2nd digit
Innervation of extensor indicis
Posterior interosseus branch of Radial nerve (C7-C8)
Action of extensor indicis
Wrist - Extension
MCP, PIP, DIP of 2nd digit - extension