Forearm & Hand Muscles Flashcards
Brachialis (Origin/Insertion)
Origin:
- Distal half of anterior surface of humerus
Insertion:
- Tuberosity and coronoid process of ulna
Brachialis (Action/Innervation)
Action:
- Flex the elbow (Humeroulnar joint)
Innervation:
- Musculocutaneous & small branch from radius (C5,6)
Extensor Carpi Radialis Longus & Brevis (Origin/Insertion)
Origin:
1. Longus:
- Distal one-third of the lateral supracondylar ridge of the humerus
2. Brevis:
- Common extensor tendon from the lateral epicondyle of the humerus
Insertion:
1. Longus:
- Base of the second metacarpal
2. Brevis:
- Base of the third metacarpal
Extensor Carpi Radialis Longus & Brevis (Action/Innervation)
Action:
- Extend the wrist (Radiocarpal joint)
- ABduct the wrist (R/C joint)
- Assist to flex the elbow (Humeroulnar joint)
Innervation:
1. Longus:
- Radial (C5,6,7,8)
2. Brevis:
- Radial (C6,7,8)
Extensor Carpi Ulnaris (Origin/Insertion)
Origin:
- Common extensor tendon from the lateral epicondyle of the humerus
Insertion:
- Base of the fifth metacarpal
Extensor Carpi Ulnaris (Action/Innervation)
Action:
- Extend the wrist (Radiocarpal joint)
- Adduct the wrist (R/C joint)
Innervation:
- Radial (C6,7,8)
Extensor Digitorum (Origin/Insertion)
Origin:
- Common extensor tendon from the lateral epicondyle of the humerus
Insertion:
- Bases of middle and distal phalanges of second through fifth fingers
Extensor Digitorum (Action/Innervation)
Action:
- Extend the second through fifth fingers (Metacarpophalangeal and interphalangeal joints)
- Assist the extend the wrist (Radiocarpal joint)
Anconeus (Origin/Insertion)
Origin:
- Lateral epicondyle of the humerus
Insertion:
- Olecranon process and posterior, proximal surface of the ulna
Anconeus (Action/Innervation)
Action:
- Extend the elbow (Humeroulnar joint)
Innervation:
- Radial (C7,8)
Extensor Indicis (Origin/Insertion)
Origin:
- Posterior surface of distal shaft of ulna and interosseous membrane
Insertion:
- Tendon of the extensor digitorum at the level of the second metacarpal
Extensor Indicis (Action/Innervation)
Action:
- Extend the second finger (Metacarpophalangeal joint)
- Adduct the second finger
- May assist to extend the wrist (Radiocarpal joint)
Innervation:
- Radial (C6,7,8)
Flexor Carpi Radialis (Origin/Insertion)
Origin:
- Common flexor tendon from the medial epicondyle of the humerus
Insertion:
- Bases of the second and third metacarpals
Flexor Carpi Radialis (Action/Innervation)
Action:
- Flex the wrist (Radiocarpal joint)
- ABduct the wrist (R/C joint)
- May assist to flex the elbow (Humeroulnar joint)
Innervation:
- Median (C6,7,8)
Palmaris Longus (Origin/Insertion)
Origin:
- Common flexor tendon from the medial epicondyle of the humerus
Insertion:
- Flexor retinaculum and palmar aponeurosis
Palmaris Longus (Action/Innervation)
Action:
- Tense the palmar fascia
- Flex the wrist (Radiocarpal joint)
- May assist to flex the elbow (Humeroulnar joint)
Innervation:
- Median (C6,7,8 & T1)
Flexor Carpi Ulnaris (Origin/Insertion)
Origin:
1. Humeral Head:
- Common flexor tendon from the medial epicondyle of the humerus
2. Ulnar Head:
- Posterior surface of proximal two-thirds of ulna
Insertion:
- Pisiform, hook of the hamate, and base of the fifth metacarpal
Flexor Carpi Ulnaris (Action/Innervation)
Action:
- Flex the wrist (Radiocarpal joint)
- Adduct the wrist (R/C joint)
- Assist to flex the elbow (Humeroulnar joint)
Innervation:
- Ulnar (C7,8 & T1)
Flexor Digitorum Superficialis (Origin/Insertion)
Origin:
- Common flexor tendon from the medial epicondyle of the humerus
- Ulnar collateral ligament
- Coronoid process of the ulna
- Interosseous membrane
- Proximal shaft of the radius
Insertion:
- Sides of middle phalanges of second through fifth fingers
Flexor Digitorum Superficialis (Action/Innervation)
Action:
- Flex the second through fifth fingers (MCP and PIP joints)
- Flex the wrist (Radiocarpal joint)
Innervation:
- Median (C7,8 & T1)
Flexor Digitorum Profundus (Origin/Insertion)
Origin:
- Anterior and medial surfaces of proximal three-quarters of ulna
Insertion:
- Bases of distal phalanges, palmar surface of second through fifth fingers
Flexor Digitorum Profundus (Action/Innervation)
Action:
- Flex the second through fifth fingers (MCP & DIP joints)
- Assist to flex the wrist (Radiocarpal joint)
Innervation:
- Second and third fingers: Median (C7,8 & T1)
- Fourth and fifth fingers: Ulnar (C7,8 & T1)
Pronator Teres (Origin/Insertion)
Origin:
- Common flexor tendon from the medial epicondyle of the humerus
- Coronoid process of the ulna
Insertion:
- Middle of lateral surface of the radius
Pronator Teres (Action/Innervation)
Action:
- Pronate the forearm (Radioulnar joint)
- Assist to flex the elbow (Humeroulnar joint)
Innervation:
- Median (C6,7)
Pronator Quadratus (Origin/Insertion)
Origin:
- Medial, anterior surface of distal ulna
Insertion:
- Lateral, anterior surface of distal radius
Pronator Quadratus (Action/Innervation)
Action:
- Pronate the forearm (Radioulnar joint)
Innervation:
- Median (C7,8 & T1)
Supinator (Origin/Insertion)
Origin:
- Lateral epicondyle of the humerus
- Radial collateral ligament
- Annular ligament
- Supinator crest of the ulna
Insertion:
- Anterior, lateral surface of proximal one-third of the Radial shaft
Supinator (Action/Innervation)
Action:
- Supinate the forearm (Radioulnar joint)
Innervation:
- Radial (C5,6,7)
Abductor Pollicis Longus (Origin/Insertion)
Origin:
- Posterior surface of radius and ulna
- Interosseous membrane
Insertion:
- Base of the first metacarpal
Abductor Pollicis Longus (Action/Innervation)
Action:
- ABduct the thumb (CMC joint)
- Extend the thumb (CMC joint)
- ABduct the wrist (Radiocarpal joint)
Innervation:
- Radial (C6,7,8)
Extensor Pollicis Longus and Brevis (Origin/Insertion)
Origin:
1. Longus:
- Posterior surface of the ulna
- Interosseous membrane
2. Brevis:
- Posterior surface of the radius
- Interosseous membrane
Insertion:
1. Longus:
- Base of distal phalanx of thumb
2. Brevis:
- Base of proximal phalanx of thumb
Extensor Pollicis Longus and Brevis (Action/Innervation)
Action:
- EPL Only: Extend the thumb (IP joint)
- Extend the thumb (MCP and CMC joints)
- ABduct the wrist (Radiocarpal joint)
Innervation:
- Radial (C6,7,8)
Flexor Pollicis Longus (Origin/Insertion)
Origin:
- Anterior surface of radius
- Interosseous membrane
Insertion:
- Base of distal phalanx of thumb
Flexor Pollicis Longus (Action/Innervation)
Action:
- Flex the thumb (IP joint)
- Flex the thumb (MCP and CMC joints)
- Assist to flex the wrist (Radiocarpal joint)
Innervation:
- Median (C6,7,8 & T1)
Abductor Pollicis Brevis (Origin/Insertion)
Origin:
- Flexor retinaculum
- Trapezium
- Scaphoid tubercles
Insertion:
- Base of proximal phalanx of thumb
Abductor Pollicis Brevis (Action/Insertion)
Action:
- ABduct the thumb (CMC and MCP joints)
- Assist in opposition of the thumb
Innervation:
- Median (C6,7,8 & T1)
Flexor Pollicis Brevis (Origin/Insertion)
Origin:
1. Superficial Head:
- Flexor retinaculum
2. Deep Head:
- Trapezium
- Trapezoid
- Capitate
Insertion:
- Base of proximal phalanx of thumb
Flexor Pollicis Brevis (Action/Innervation)
Action:
- Flex the thumb (CMC and MCP joints)
- Assist in opposition of the thumb
Innervation:
1. Superficial Head:
- Median (C6,7,8 & T1)
2. Deep Head:
- Ulnar (C8 & T1)
Opponens Pollicis (Origin/Insertion)
Origin:
- Flexor retinaculum
- Tubercle of the trapezium
Innervation:
- Entire length of first metacarpal bone, radial side
Opponens Pollicis (Action/Innervation)
Action:
- Opposition of the thumb at the CMC joint (bringing the pads of the thumb and fifth fingers together)
Innervation:
- Median (C6,7,8 & T1)
Adductor Pollicis (Origin/Insertion)
Origin:
- Capitate
- Second and third metacarpals
Insertion:
- Base of proximal phalanx of thumb
Adductor Pollicis (Action/Innervation)
Action:
- Adduct the thumb (CMC and MCP joints)
- Assist to flex the thumb (MCP joint)
Innervation:
- Ulnar (C8 & T1)
Lumbricals of the Hand (Origin/Insertion)
Origin:
- Surfaces of the flexor digitorum profundus tendons
Insertion:
- Extensor aponeurosis on dorsal surface of phalanges
Lumbricals of the Hand (Action/Innervation)
Action:
- Extend the second through fifth fingers at the IP joints
- Flex the second through fifth fingers at the MCP joints
Innervation:
1. Second and third fingers:
- Median (C6,7,8 & T1)
2. Fourth and fifth fingers:
- Ulnar (C7,8 & T1)
Palmar Interossei (Origin/Insertion)
Origin:
- Base of first, second, fourth and fifth metacarpals
Insertion:
- Base of the proximal phalanx of the related finger and the extensor aponeurosis
Palmar Interossei (Action/Innervation)
Action:
- Adduct the thumb, second, fourth, and fifth fingers toward the third finger
- Assist to flex the thumb, second, fourth, and fifth fingers at the MCP joints
- Assist to extend the thumb, second, fourth, and fifth fingers at the IP joints
Innervation:
- Ulnar (C8 & T1)
Dorsal Interossei (Origin/Insertion)
Origin:
- Adjacent sides of all metacarpals
Insertion:
- Base of the proximal phalanx of the second, third, and fourth fingers
- Extensor aponeurosis
Dorsal Interossei (Action/Innervation)
Action:
- ABduct the second, third, and fourth fingers at the MCP joints
- Assist to flex the second, third, and fourth fingers at the at the MCP joints
- Assist to extend the second, third, and fourth fingers at the IP joints
Innervation:
- Ulnar (C8 & T1)
Abductor Digiti Minimi (Origin/Insertion)
Origin:
- Pisiform
- Tendon of the flexor carpi Ulnaris
Insertion:
- Base of proximal phalanx of the fifth finger, ulnar surface
Abductor Digiti Minimi (Action/Innervation)
Action:
- ABduct the fifth finger (MCP joint)
- Assist in opposition of the fifth fingers toward the thumb (MCP joint)
Innervation:
- Ulnar (C7,8 & T1)
Flexor Digiti Minimi Brevis (Origin/Insertion)
Origin:
- Hook of the hamate
- Flexor retinaculum
Insertion:
- Base of the proximal phalanx of fifth fingers, palmar surface
Flexor Digiti Minimi Brevis (Action/Innervation)
Action:
- Flex the fifth finger (MCP joint)
- Assist in opposition of the fifth finger toward the thumb
Innervation:
- Ulnar (C7,8 & T1)
Opponens Digiti Minimi (Origin/Insertion)
Origin:
- Hook of the hamate
- Flexor retinaculum
Insertion:
- Shaft of fifth metacarpal, ulnar surface
Opponens Digiti Minimi (Action/Innervation)
Action:
- Opposition of the fifth finger at the CMC joint
Innervation:
- Ulnar (C7,8 & T1)
