Forearm mm - Origin, Insertion

Question 1

What mm originate on the common extensor origin (lateral epicondyle)? (6)

***supinator and all superficial mm of post forearm except BR & ECRL

Answer 1

ECRB
ED
EDM
ECU
anconeus
supinator (part of it)

Question 2

What 2 muscles originate on the lateral supracondylar ridge?

Answer 2

brachioradialis (proximal 2/3)

ECRL (distal 1/3)

Question 3

brachioradialis

Answer 3

O - proximal 2/3 of lateral supracondylar ridge

I - lat distal radius, proximal to styloid process

Question 4

Extensor Carpi Radialis Longus

Answer 4

O - distal 1/3 of lateral supracondylar ridge

I - dorsal base of 2nd MC

Question 5

Extensor Carpi Radialis Brevis

Answer 5

O - lateral epicondyle of humerus (common extensor origin)

I - dorsal base of 3rd MC

Question 6

Extensor Digitorum

Answer 6

O - lateral epicondyle of humerus (common extensor origin)

I - dorsal middle and distal phalanges of digits 2-5 via extensor expansion

Question 7

Extensor Digiti minimi

Answer 7

O - lateral epicondyle of humerus (common extensor origin)

I - dorsal digital expansion of 5th MC

Question 8

Extensor Carpi Ulnaris

Answer 8

O - lat epicondyle of humerus (common extensor origin), posterior border ulna

I - dorsal medial side of base of 5th MC

Question 9

Anconeus

Answer 9

O - lateral epicondyle of humerus (common extensor origin)

I - lateral olecranon, post ulnar shaft

Question 10

Supinator

Answer 10

O - lat epicondyle of humerus, LCL & annular ligaments of elbow

I - lat proximal 1/3 radius

Question 11

Extensor Indicis

Answer 11

O - post distal 1/3 of ulna and interosseus membrane

I - extensor hood of index finger (2nd digit)

Question 12

Abductor Pollicis Longus

Answer 12

O - post radius and ulna (lateral to EPB) and int membrane

I - radial side base of 1st MC

Question 13

Extensor Pollicis Longus

Answer 13

O - post shaft of middle 1/3 ulna, int membrane

I - base of dorsal distal phalanx of thumb

Question 14

Extensor Pollicis Brevis

Answer 14

O - post surface distal 1/3 of radius, int membrane

I - base of proximal phalanx of thumb (dorsal side)

Question 15

Origin of all anterior superficial forearm muscles?

Answer 15

medial epicondyle of humerus (common flexor tendon)

Question 16

What mm originate on the common flexor tendon (medial epicondyle)? (5)

***all 4 mm of sup layer (“PFPF”) and part of FDS

Answer 16

pronator teres
FCR
PL
FCU
humeroulnar head of FDS

Question 17

Pronator Teres

Answer 17

Humeral head O - medial epicondyle of the humerus (common flexor tendon)

Ulnar head O - coronoid process of ulna

I - middle lateral radius

Question 18

Flexor Carpi Radialis

Answer 18

O - medial epicondyle of humerus (common flexor tendon)

I - base of the 2nd MC

Question 19

Palmaris Longus

Answer 19

O - medial epicondyle of humerus (common flexor tendon)

I - ant flexor retinaculum and palmar aponeurosis (hand)

Question 20

Flexor Carpi Ulnaris

Answer 20

Humeral head O - medial epicondyle of humerus (common flexor tendon)

Ulnar head O - medial olecranon, posterior ulna

I - pisiform bone, hook of hamate, 5th MC

Question 21

Flexor Digitorum Superficialis

Answer 21

Humeroulnar head O - medial epicondyle of humerus (common flexor tendon) & coronoid process of ulna

Radial head O - sup half of the anterior surface of the radius (distal to radial tuberosity)

I - 4 long tendons into the middle phalanx of digits 2-5

Question 22

Flexor Digitorum Profundus

Answer 22

O - upper 3/4 of the anterior and medial aspects of the ulna and ulnar 1/2 of the interosseus membrane

I - base of the distal phalanx of digits 2-5

Question 23

Flexor Pollicis Longus

Answer 23

O - ant radius and interosseus membrane

I - palmar base of distal phalanx of thumb

Question 24

Pronator Quadratus

Answer 24

O - distal 1/4 of ant ulna

I - distal 1/4 of ant radius

Question 25

Muscle group that originate in the forearm and control thumb movement

Answer 25

posterior forearm/outcropping group