Nerves of Arm

Question 1

axillary nerve

Answer 1

C5-6; deltoids and teres minor and sensory to lateral delotid

MOI: humeral head disloc, fracture of surgical neck, brachial plexitis

ssx: weakness of 15-30° abduction, outward, backward and forward; sensory loss on lat deltoid

Question 2

long thoracic nerve

Answer 2

C5-7; serratus ant

aka hod carrier’s palsy

MOI: carrying heavy loads, acute impact or downward force on shoulder

ssx: scap winging, 90-180° abd

Question 3

brachial cutaneous and antebrachial cutaneous nerves

Answer 3

sensation to medial arm and upper 2/3 of forearm; C8-T1

injury to medial cord of BP

Question 4

suprascapular nerve

Answer 4

C5-6

innervates supraspinatus and infraspinatus

shoulder trauma or diffuse brachial injury

weakness in 15-30° abd and ER of shoulder

Question 5

radial nerve

Answer 5

from post cord of BP and contains C5-T1

forearm, wrist and finger ext, supinator

sensory to dorsoradial distal forearm and dorsal hand

Question 6

axilla or high radial nerve lesion

Answer 6

improper fit of crutches

triceps, brachioradialis, ECR and EDC weakness

sensory loss on dorsolateral arm, forearm and hand

Question 7

radial nerve injury in spiral groove

Answer 7

humeral fractures, saturday night palst

wrist drop, diff extending fingers

senosry loss on dorsal hand, thumb, index and middle

intact triceps and mild brachioradialis weakness

radial nerve palsy

Question 8

posterior interosseous nerve injury

Answer 8

compression at supinator muscle on arcade of frohse

radial dev upon ext

no sensory loss

weal EDC, EI, APL; finger ext

post interosseous syndrom

Question 9

superficial radial nerve injury

Answer 9

tight fitting jewelry on wrist, handcuffs, pressure

pure sensory loss on dorsum of hand and 1st 3 digits and part of 4th

wartenberg’s

Question 10

median nerve

Answer 10

pronator teres and quadratus

FCR, FDS, FDP, OP, PL and lumbricals

sensory to radial palm, ventral 1st 3 digits and half of 4th; radial of distal phalanges

Question 11

pronator teres syndrome

Answer 11

entrapment of median nerve at pronator teres

weak FCR, PL, FDS and pronator quadratus

intact pronator teres

sensory loss on area of median

weak wrist, thumb, index and middle flexion

Question 12

anterior interosseous nerve syndrome

Answer 12

entrapment of ant interosseous

pain in forearm

no sensory loss

wek FPL, FDP and pronator quadratus

ok sign abnormality

Question 13

CTS

Answer 13

entrapment at carpal tunnel on transverse carpal ligament

pain and sensory loss on distal median

weakness and wasting og thenar muscles and lumbricals

Question 14

median nerve lesion wrist

Answer 14

repetitive use and poor ergonomics

weakness in thumb flexion and opposition

sensory on radial palm and 1st 3 digits

tingling and burning

Question 15

lacertus fibrosus

Answer 15

same to pronator teres syndrome but pronator teres not spared

Question 16

ulnar nerve

Answer 16

from C8-T1

sensory to little finger and medial half of ring, palmar and dorsal of ulnar hand

FCU, FDP 3/4, hypothenar, adductor pollicis, FPB

Question 17

proximal ulnar nerve lesion

Answer 17

weakness of flex-add of wrist, flexion of ring and little, abd and opp of little, add of thumb, add and abd of fingers

sesnory loss on little and ring

Question 18

chronic ulnar nerve lesions

Answer 18

claw hand - atrophy of intrisnic muscle

Question 19

compression at the elbow

Answer 19

cubital tunnel at ulnar groove

arm of chairs, edges, prolonged elbow felxion

weakness in ulnar myotomes - FCU, FDP 3/4

sensory on ring and littel

Question 20

canal of guyon syndrome

Answer 20

ganglion cysts at guyon’ canal

weakness and atrophy of intrinsics, hypothenar and add pollicis

sensory on little and ring

spared FCU and FDP 3/4 as well as sensory on dorsal hand

ulnar tunnel syndrome