Forearm/hand joint Flashcards
Extensor carpi radialis longus
Origin -
lateral supracondylar ridge of the humerus
The lateral intermuscular septum of the arm
Insertion- base of the second metacarpal bone
Action -Extends the hand at the wrist joint, Abducts the hand at the wrist and midcarpal joints
Innervation - The radial nerve
Extensor carpi radialis brevis
Origin -Lateral epicondyle of the humerus
Insertion- base of the third metacarpal bone
Action - Wrist extension and hand abduction
Innervation -Deep branch of the radial nerve
Extensor indicis
Origin - distal ulna and interosseous membrane
Insertion: Extensor expansion of the index finger
Action: Extends the index finger
Innervation: Posterior interosseous nerve (C7, C8)
Extensor digitorum
Origin - Lateral epicondyle of the humerus
Insertion: middle and distal phalanges of digits 2-5 (index, middle, ring, and little fingers)
Action: Extends the fingers at the metacarpophalangeal and interphalangeal joints
Innervation: Posterior interosseous nerve (a branch of the radial nerve
Extensor digiti minimi
Origin: Lateral epicondyle of the humerus
Insertion: Extensor expansion of the little finger
Action: Extends the little finger
Innervation: Posterior interosseous nerve (C7, C8)
Extensor carpi ulnaris
Origin: Lateral epicondyle of the humerus and posterior border of the ulna
Insertion: Base of the fifth metacarpal bone
Action: Wrist extension and ulnar deviation (adduction)
Innervation: Posterior interosseous nerve (C7, C8)
Abductor pollicis longus
Origin - posterior surfaces of the radius and ulna bones
Insertion- lateral aspect of the base of the first metacarpal bone
Action - abducts the thumb and extends it at the carpometacarpal joint
Innervation -posterior interosseous nerve
extensor pollicis brevis
Origin: distal radius and adjacent interosseous membrane
Insertion: Base of the proximal phalanx of the thumb
Action: Extends the thumb at the carpometacarpal and metacarpophalangeal joints
Innervation: Posterior interosseous nerve (C7, C8)
Extensor pollicis longus
Origin: middle third of the ulna and the interosseous membrane
Insertion: Base of the distal phalanx of the thumb
Action: Extends the thumb at the metacarpophalangeal and interphalangeal joints
Innervation: Posterior interosseous nerve (a branch of the radial nerve)
Flexor carpi radialis
Origin: Medial epicondyle of the humerus
Insertion: Base of the second and third metacarpal bones
Action: Wrist flexion and radial deviation (hand abduction)
Innervation: Median nerve (C6-C7)
Palmaris longus
Origin - medial epicondyle of the humerus.
Insertion- palmar aponeurosis and the distal half of the flexor retinaculum.
Action - flexes the hand at the wrist
Innervation - median nerve (C7, C8)
Flexor carpi ulnaris
Origin: Medial epicondyle of humerus (humeral head), olecranon and posterior border of ulna (ulnar head)
Insertion: Pisiform bone, hook of hamate, and base of the 5th metacarpal bone
Action: Wrist flexion and adduction
Innervation: Ulnar nerve (C7-T1)
flexor digitorum superficialis
Origin -
Humeral head: Medial epicondyle of humerus
ulnar head: coronoid process of ulna
Radial head: below radial tuberosity
Insertion- Sides of middle phalanges of digits 2-5
Action -flexes the proximal interphalangeal (PIP) and metacarpophalangeal (MCP)
Innervation - the median nerve
Flexor pollicis longus
Origin: The anterior surface of the radius and the interosseous membrane of the forearm
Insertion: base of the thumb’s distal phalanx
Action: Flexes the thumb’s interphalangeal and metacarpophalangeal joints. It may also help flex the wrist
Innervation: The anterior interosseous nerve, which comes from the median nerve
Flexor digitorum profundus
Origin - Proximal half of anterior surface of ulna, interosseous membrane
Insertion-distal phalanges of digits 2-5
Action -Metacarpophalangeal and interphalangeal joints 2-5: Finger flexion
Innervation -
The medial part of the FDP is innervated by the ulnar nerve
The lateral part of the FDP is innervated by the anterior interosseous branch of the median nerve
