PT 671 Wrist, Hand, Forearm & Elbow Muscles

Question 1

Pronator Teres m.

Answer 1

Ulnar head: coronoid process of ulna
Humeral head: medial epicondyle of humerus

Middle of convexity of lateral surface of radius

Median nerve

C7

Pronates and flexes forearm at elbow

Question 2

Flexor Carpi Radialis m.

Answer 2

Medial epicondyle of humerus
Base of 2nd metacarpal
Median nerve
C7
Flexes and ABDucts hand at wrist

Question 3

Palmaris longus m.

Answer 3

Medial epicondyle of humerus
Distal half of flexor retinaculum & apex of palmar aponeurosis
Median nerve
Flexes hand at wrist and tenses palmar aponeurosis

Question 4

Flexor carpi ulnaris m.

Answer 4

Ulnar head: olecranon of ulna
Humeral head: medial epicondyle of humerus

Pisiform, hook of hamate, 5th metacarpal

Ulnar nerve

C8

Flexes and ADD hand at wrist

Question 5

Flexor digitorium superficialis m.

Answer 5

Humero-ulnar head: medial epicondyle of humerus; coronoid process of ulna
Radial head: superior half of anterior boarder

Shafts of middle phalanges

Median nerve

Flexes middle phalanges at proximal interphalangeal joints of middle 4 digits; also flexes proximal phalanges at metacarpophalangeal joint

Question 6

Flexor digitorum profundus m.

Answer 6

proximal 3/4 of medial and anterior surfaces of ulna and interosseous membrane

Medial part: bases of distal phalanges of 4th and 5th digits
Lateral part: bases of distal phalanges of 2nd and 3rd digits

Medial: ulnar nerve
Lateral: anterior interosseous nerve (from medial nerve)

C8,T1

Medial: flexes distal phalanges 4 and 5 at distal interphalangeal joints
Lateral: flexes distal phalanges 2 and 3 at distal interphalangeal joints

Question 7

Flexor pollicis longus m.

Answer 7

Anterior surface of radius and adjacent interosseous membrane
Base of distal phalanx of thumb
Anterior interosseous nerve
C8
Flexes phalanges of thumb

Question 8

Pronator quadratus m.

Answer 8

Distal 1/4 of anterior ulnar surface
Distal 1/4 of anterior surface of radius
Anterior interosseous nerve
C8
Pronates forearm; deep fibers bind radius and ulna together

Question 9

Extensor carpi radialis longus m.

Answer 9

Lateral supracondylar ridge of humerus
Dorsal aspect of base of 2nd metacarpal
Radial nerve
Extend and ABD hand at wrist joint; ECRL active during fist clenching

Question 10

Extensor carpi radialis brevis m.

Answer 10

Lateral epicondyle of humerus
Dorsal aspect of based of 3rd metacarpal
Deep branch of radial nerve
C7
Extend and ABD hand at wrist joint; ECRL active during fist clenching

Question 11

Extensor digitorum m.

Answer 11

Lateral epicondyle of humerus
Extensor expansions of medial 4 digits
Deep branch of radial nerve
C7
Extends medial four digits primarily at metacarpophalangeal joints, secondarily at interphalangeal joints

Question 12

Extensor digiti minimi m.

Answer 12

Lateral epicondyle of humerus
Extensor expansion of 5th digit
Deep branch of radial nerve
C7
Extends 5th digit primarily at metacarpophalangeal joint, secondariliy at interphalangeal joint

Question 13

Extensor carpi ulnaris m.

Answer 13

Lateral epicondyle of humerus; posterior border of ulna via shared aponeurosis
Dorsal aspect of base of 5th metacarpal
Deep branch of radial nerve
C7
Extends and ADD hand at wrist joint (also active during fist clenching)

Question 14

Supinator m.

Answer 14

Lateral epicondyle of humerus; radial collateral and anular ligaments; supinator fossa; crest of ulna
Lateral, posterior, and anterior surfaces of proximal 1/3 of radius
Deep branch of radial nerve
C8
Supinates forearm; rotates radius to turn palm anteriorly or superiorly (if elbow is flexed)

Question 15

Extensor indicis m.

Answer 15

Posterior surface of distal 1/3 of ulna and interosseous membrane
Extensor expansion of 2nd digit
Posterior interosseous nerve
C7,C8
Extends 2nd digit (enabling its independent extension); helps extend had at wrist

Question 16

Abductor pollicis longus m.

Answer 16

Posterior surface of proximal halves of ulna, radius, and interosseous membrane
Base of 1st metacarpal
Posterior interosseous nerve
C8
Extends wrist joint, ABD thumb and extends it at carpometacarpal joint

Question 17

Extensor pollicis longus m.

Answer 17

Posterior surface of middle 1/3 of ulna and interosseous membrane
Dorsal aspect of base of distal phalanx of thumb
Posterior interosseous nerve
C8
Extends wrist joint; extends distal phalanx of thumb at interphalangeal joint; extends metacarpophalangeal and carpometacarpal joints

Question 18

Extensor pollicis brevis m.

Answer 18

Posterior surface of distal 1/3 of radius and interosseous membrane
Dorsal aspect of base of proximal phalanx of thumb
Posterior interosseous nerve
C8
Extends wrist joint, extends proximal phalanx of thumb at metacarpophalangeal joint; extends carpometacarpal joint

Question 19

Biceps brachii m.

Answer 19

Short head: tip of coracoid process of scapula
Long head: supraglenoid tubercle of scapula

Tuberosity of radius and fascia of forearm via bicipital aponeurosis

Musculocutaneous Nerve

C6

Supinates Forearm, and When it is Supine, Flexes Forearm; Short Head Resists Dislocation of Shoulder

Question 20

Brachialis m.

Answer 20

Distal half of anterior surface humerus
Coronoid process and tuberosity ulna
Musculocutaneous and Radial Nerve
Flexes Forearm in All Positions

Question 21

Brachioradialis m.

Answer 21

Proximal 2/3 of supra-epicondylar ridge of humerus
Lateral surface of distal end of radius proximal to styloid process
Radial nerve
C6
Relatively weak flexion of forearm; maximal when forearm is in midpronated position

Question 22

Triceps brachii m.

Answer 22

Long head: infraglenoid tubercle of scapula
Lateral head: posterior surface of humerus, superior to radial groove
Medial head: posterior surface of humerus, inferior to radial groove

Proximal end of olecranon of ulna and fascia of forearm

Radial Nerve

C7

Chief Extensor of Forearm; Long Head Resists Dislocation of Humerus; Especially Important During Adduction

Question 23

Anconeus m.

Answer 23

just know where it is