Anterior Forearm Muscles

Question 0

Flexor Carpi Radialis (FCR) Origin? Insertion? Innervation? Action?

Answer 0

O: Medial epicondyle of humerus

I: Base of 2nd (3rd) metacarpal

Innervation: Median nerve C6 and C7

Action: Flexes and abducts hand at wrist

Question 1

Pronator teres Origin? Insertion? Innervation? Action?

Answer 1

O: Ulnar head-> Coronoid process of ulna
Humeral head-> Medial epicondyle of humerus

I: Middle of convexity of lateral surface of radius

Innervation: Median nerve (C6 and C7)

Action: Pronates and flexes forearm at elbow

Question 2

Palmaris longus Origin? Insertion? Innervation? Action?

Answer 2

O: Medial epicondyle of humerus

I: Distal half of flexor retinaculum, palmar aponeurosis

Innervation: Median nerve (C7 and C8)

Action: Flexes hand at wrist and tenses palmar aponeurosis

Question 3

Flexor Carpi Ulnaris (FCU) Origin? Insertion? Innervation? Action?

Answer 3

O: Olecranon and posterior border via aponeurosis, and medial epicondyle

I: Pisiform, hook of hamate, 5th metacarpal

Innervation: Ulnar nerve (C7 and C8)

Action: Flexes and ulnar deviation at wrist

Question 4

Flexor Digitorum Superficialis (FDS) Origin? Insertion? Innervation? Action?

Answer 4

O: Humero-ulnar head-> medial epicondyle of humerus and coronoid process of ulna Radial head-> oblique line of radius

I: Shafts of middle phalanges of medial 4 digits

Innervation: Median nerve (C7, C8, and T1)

Action: Flexes proximal interphalangeal joints of middle 4 digits; acting more strongly, it also flexes proximal phalanges at metacarpophalangeal joints

Question 5

Flexor Digitorum Profundus (FDP) Origin? Insertion? Innervation? Action?

Answer 5

O: Proximal 3/4 of medial and anterior surfaces of ulna and interosseous membrane

I: Bases of distal phalanges of 2nd-5th digits

Innervation: (Digits 2-3) median nerve C8 and T1 anterior interosseous branch; (Digits 4-5) ulnar nerve C8 and T1

Action: Flexes distal interphalangeal joints of digits 2-5 and assists with wrist flexion

Question 6

Flexor Pollicis Longus (FPL) Origin? Insertion? Innervation? Action?

Answer 6

O: Anterior surface of radius and adjacent interosseous membrane

I: Base of distal phalanx of thumb

Innervation: Anterior interosseous nerve from median nerve (C8 and T1)

Action: Flexes phalanges of 1st digit

Question 7

Pronator Quadratus Origin? Insertion? Innervation? Action?

Answer 7

O: Distal quarter of anterior surface of ulna

I: Distal quarter of anterior surface of radius

Innervation: Anterior interosseous nerve from median nerve (C8 and T1)

Action: Pronates forearm; deep fibers bind radius and ulna together