brachial plexus, UE nerve pathology 1/14

Question 1

what pathology? what nerve?
wrist is compressed with tight jewelry over its lateral aspect, the superficial branch of the ___ nerve will be compressed beneath the tendinous insertion of brachioradialis.
- symptoms: loss of sensation of the dorsal aspect of the radial 3 and half fingers, as well as the centre of the forearm posteriorly.

Answer 1

• Wartenberg’s syndrome

- radial n

Question 2

what pathology? what nerve?
If someone is drunk, they often rest their armpit on chairs and fall asleep. When they wake up, they suffer from wrist drop, since ___ nerve has been compressed long time

Answer 2

• Saturday night palsy/crutch palsy

- radial nerve - behind the axillary artery, and hence is vulnerable to compression injuries.

Question 3

what nerve affected?

wrist drop

Answer 3

radial n

Question 4

what nerve affected?
claw
- hyperextension at the 4-5th MCP
- flexion at the 4-5th PIP and DIP

Answer 4

ulnar n
hyperextension at the MCP - lumbricles 3-4
and flexion at the PIP and DIP of the 4th and 5th fingers - FDP (ulnar half)

Question 5

what nerve affected?

ape hand - limited thumb movement, thumb not able to abduct or oppose

Answer 5

median n
recurrent motor branch denervated, unopposable thumb - abductor pollicis brevis, flexor pollicis brevis, opponens pollicis and the two radial lumbricals.

Question 6

what nerve affected?
humeral shaft fracture
symptoms: unable extend the elbows, wrist drop, diminished sensation on almost the entire posterior surface of the arm and forearm.

Answer 6

radial n

Question 7

what nerve affected?

humeral surgical neck fracture

Answer 7

axillary nerve

posterior circumflex humeral artery

Question 8

what nerve affected? what test used?
Carpal tunnel syndrome
thenar muscle wasting and weakness

Answer 8

median n

tests: tinels (tapping carpal tunnel), phalen’s test (hold 60 sec cause paresthesia)
- long finger flexors become swollen due to overuse (typist), or edema (pregnancy), then the median nerve becomes compressed. This results in pain, paresthesia and numbness (tingling and pins and needles) of the lateral three and a half fingers.

Question 9

what nerve affected? where is it damaged?
hand of benediction
unable to flex 2-3rd digit, cannot make a fist

Answer 9

median n
at elbow - supracondylar fracture
- radial head of flexor digitorum profunda and lumbricles 1-2 being denervated unable flex MCP and IPs for 2-3rd digits

Question 10

what nerve affected? symptoms?

pronator syndrome

Answer 10

median nerve can become trapped between the two heads of pronator teres, resulting in wrist flexor wasting.

Question 11

what nerve affected? 
stab wound to the axilla
- weak elbow flex
- weak supination
- loss sensation lateral part of the forearm

Answer 11

musculocutaneous n

• able to flex elbow - brachioradialis (radial n)
• able to supinate at shoulder - supinator (radial n), pec major (med/lat pectoral n)

Question 12

what nerve injured?

Cyclists rest the lateral border of their hand on their handlebars, resulting in hamate and ___ nerve compression.

Answer 12

ulnar n

Question 13

what nerve?
Cubital tunnel syndrome
- hit funny bone, rests their elbow on the table for a long time or window (for long distance drivers) compress nerve
- weakness of medial forearm hand muscles
- loss of sensation medial hand

Answer 13

ulnar n - cubital tunnel syndrome

Question 14

what nerve injured?
athletic injury whilte throwing e.g. baseball pitchers, javelin throwers due to rapid transfer of the elbow from hyperextension into whip-like flexion results in nerve compression
- pins and needles sensation medial lower forearm and 4-5th digits
- weakness of the medial side of the forearm and hand muscles

Answer 14

ulnar n - cubital tunnel syndrome