The Forearm

Question 1

The tendons of most the flexor muscles pass across the anterior surface of the wrist…which ligament are they held in place by?

Answer 1

The palmar carpal ligament and the flexor retinaculum (the transverse carpal ligament)

Question 2

What are the 3 layers of the anterior muscles in the forearm?

Answer 2

The superficial layer- four muscles

The intermediate layer- one muscle

The deep layer- 3 muscles

Question 3

Which muscles are in the anterior superficial compartment of the forearm?

Answer 3

1. The pronator teres
2. The flexor carpi radialis
3. The palmaris longus
4. The flexor carpi ulnaris

These muscles all attach proximally by a common flexor tendon to the medial epicondyle of humerus

Question 4

What are the muscles in the intermediate layer of the anterior compartment of the arm?

Answer 4

The flexor digitorum superficialis

Question 5

What muscles are in the deep layer of the anterior compartment of the forearm?

Answer 5

1. The flexor digitorum profundus
2. The flexor pollicis longus
3. The pronator quadratus

Question 6

Which compartment are the flexor-pronator muscles in?

Answer 6

The anterior compartment of the forearm

Question 7

Which muscles of the anterior compartment of the forearm cross the elbow joint?

Answer 7

The fiver superficial and intermediate muscles but not the three deep muscles

Question 8

The brachioradialis is a flexor muscle..Which compartment is it in in the forearm?

Answer 8

Confusingly, the posterior, thus is supplied by the radial nerve. A major exception as usually the radial nerve supplies the extensor muscles in the forearm.

Question 9

What is the origin and insertion of the pronator teres?

Answer 9

Origin- ulnar head- corocoid process
Radial head-medial epicondyle of the humerusi

Insertion- middle of convexity of the lateral surface of the radius

Innervates by the median nerve

Question 10

What is the origin and insertion of the flexor carpi radialis?

Answer 10

Origin- the medial epicondyle of the humerus

Insertion- base of 2nd metacarpal

Flexes and adducts hand at wrist

Question 11

What is the origin and insertion of the palmaris longus?

Answer 11

Origin- medial epicondyle of the humerus

Insertion- distal half of flexor retinaculum, Palma apaneurosis

Flexes hand at wrist and tenses palmar aponeurosis

Question 12

What is the origin and insertion of the flexor carpi ulnaris?

Answer 12

Origin- olecranon and posterior border

Insertion- pisiform, hook of hannate, 5th metacarpals

Innervated by the ulnar nerve

Flexes and adducts hand at the wrist

Question 13

What is the origin and insertion of the flexor digitorum superficialis?

Answer 13

Origin- humeral-ulnar head- medial epicondyle of the humerus and corocoid process of the ulna
Radial head- oblique line of the radius

Insertion- shafts of middle phalanges of medial 4 digits

Question 14

What is the origin and insertion of the flexor digitorum profundus?

Answer 14

Origin- proximal 3/4 of medial and anterior surfaces of the ulnar and interosseus membrane

Insertion- bases of distal phalanges of 2nd, 3rd, 4th and 5th digits.

Flexes distal interphalangeal joints of digits, assists with wrist flexion

Question 15

What is the origin and insertion of the flexor pollicis longus?

Answer 15

Origin- the anterior surface of the radius and adjacent interosseus membrane

Insertion- base of distal phalanx of thumb

Innervated by anterior interosseus nerve from the medial nerve

Flexes the phalanges of the thumb

Question 16

What is the origin and insertion of the pronator quadratus?

Answer 16

Origin- distal quarter of anterior surface of the ulna

Insertion- distal quarter of anterior surface of radius

Innervate by interosseus nerve from the medial nerve

Pronates the forearm, deep fibers bind the radius and ulnar together.