nerve injury of upper limb continuation

Question 1

what branch does the ulnar nerve come from

Answer 1

the medial chord of the brachial plexus

Question 2

where is the ulnar nerve located in the arm

Answer 2

lies medial to the axillary artery

passes posteriorly to the medial epicondyle of humerus

Question 3

where is the ulnar nerve located in the forearm

Answer 3

enters between 2 heads of flexor carpi ulnaris

passes down medially between flexor carpi ulnaris and flexor digitorum profundus

Question 4

where is the ulnar nerve located at the wrist

Answer 4

it lies lateral to the tendon of flexor carpi ulnaris & superficial to the flexor retinaculum (this is a dangerous position)

Question 5

does the ulnar nerve branch in the arm?

Answer 5

no

Question 6

what branches does the ulnar nerve spilt into in the forearm

Answer 6

1. Muscular branches to the flexor carpi ulnaris and to the medial 1/2 of the flexor digitorum profundus.
2. Palmar branch: supply skin on the medial 1/3 of the palm.
3. Dorsal branch: supplies the skin of the medial 1/3 of the dorsal surfaces of the hand & the medial 1 ½ fingers.

Question 7

what branches does the ulnar nerve supply in the hand

Answer 7

1. Deep branch supplies the interossei, adductor pollicis, and the 2 medial lumbricals.
2. Superficial branch supplies palmaris brevis muscle skin on the palmar surface of the medial 1 ½ fingers.

Question 8

what could be the cause of Loss of wrist adduction with weak wrist flexion, due to loss of function of flexor carpi ulnaris.

Answer 8

injury to the ulnar nerve behind the medial epicondyle

Question 9

what could be the effect of elbow joint dislocation or fracture of the medial epicondyle of the humerus

Answer 9

Injury of the ulnar nerve behind the medial epicondyle:

Question 10

clawed hand is a sign of injury to what nerve

Answer 10

to the ulnar nerve

Question 11

what are the position of the hand when claw hand is suspected

Answer 11

Clawing is less pronounced in the lateral fingers because the lateral 2 lumbricals are innervated by the median nerve ;while the function of all intrinsic muscles of medial digits is lost.

Question 12

what causes injury to the ulnar at the wrist

Answer 12

Open trauma at the wrist.

Nerve compression by tumors (ulnar tunnel)

Question 13

what would be suspected if there is Loss of sensation in skin on the palmar surface of the medial 1 ½ fingers (Superficial branch).

Answer 13

injury of the ulnar nerve at the wrist

Question 14

which branch of the brachial plexus does the radial nerve come from

Answer 14

branch of the posterior cord

Question 15

what is the position of the radial nerve in the arm

Answer 15

Crosses the radial groove from medial to lateral.

On the lateral side of the arm, it passes anteriorly through piercing the lateral intermuscular septum.

Question 16

what is the position of the radial nerve in the arm

Answer 16

Enters the forearm between the brachialis and the brachioradialis muscles.
Divides into deep (motor) and superficial (cutaneous) branches.
The deep branch pierces supinator to enter the back of forearm.
The radial nerve supplies the lateral part of brachialis, triceps , anconeus, brachioradialis and extensor carpi radialis longus.

Question 17

what branches does the radial nerve have in the axilla

Answer 17

Muscular branches to the triceps.

Posterior cutaneous nerve of the arm which supplies the skin of back of arm.

Question 18

what branches does the radial nerve have in the arm

Answer 18

Muscular branches to the triceps, anconeus, brachialis, brachioradialis and to extensor carpi radialis longus.

Lower lateral cutaneous nerve of the arm supplies the skin over the lateral and anterior aspects of the lower part of the arm.

Posterior cutaneous nerve of forearm supplies the skin of back of forearm

Question 19

how does the radial nerve branch in the forearm

Answer 19

The deep branch of the radial nerve: Innervates the extensor carpi radialis brevis and supinator muscle then emerges between its 2 heads as posterior interosseous nerve.

Question 20

what is the posterior interosseous nerve

Answer 20

Is the continuation of the deep branch of radial nerve.

It supplies the remaining extensor muscles of the forearm.

Question 21

what does the superficial branch of the radial nerve supply

Answer 21

Supplies the skin of the lateral 2/3 of the dorsal surface of the hand and the skin of the dorsal surface of the lateral 3½ fingers except the distal phalanges which are supplied by median nerve.

Question 22

which nerve would a fracture of the mid shaft of the humerus

Answer 22

radial nerve

Question 23

what would be the effect of a injury to the radial nerve in the radial(spiral) groove

Answer 23

Wrist drop (loss of function of forearm extensors ).
Loss of sensation on the skin of the lower lateral arm, back of forearm & dorsal surface of the lateral 2/3 of hand with lateral 3½ fingers .