4- clinical anatomy of upper limb

Question 1

what nerve roots does musculocutaneous nerve arise from?

Answer 1

C5,6,7

Question 2

what nerve roots does axillary nerve arise from?

Answer 2

C5,6

Question 3

what nerve roots do the radial & median nerves arise from?

Answer 3

radial = C6,7,8
median = C6,7,8, T1

Question 4

what nerve roots does ulnar nerve arise from?

Answer 4

C8, T1

Question 5

what nerve is likely damaged in shoulder dislocation or neck humerus fracture?

Answer 5

axillary nerve

Question 6

what is sensory deficit if damaged axillary nerve?

Answer 6

regimental patch/ badge patch numbness (superolateral aspect of arm)

Question 7

what is motor deficit if damaged axillary nerve?

Answer 7

not complete abduction (would be able to start abduction with supraspinatus muscle but not finish as deltoid muscle which is supplied by axillary nerve)

*also some lateral rotation problems as supplies teres minor

Question 8

what is the quadrangular space?

Answer 8

= passageway in shoulder allowing axillary nerve & posterior humeral circumflex artery

• made by teres minor, teres major,, long head of triceps brachii, humerus

Question 9

what nerve is likely to be damaged if mid shaft humeral fracture?

Answer 9

radial nerve

Question 10

what is sensory & motor deficit of radial nerve injury?

Answer 10

sensory = base of thumb
motor = extension

Question 11

what is clinical presentation of radial nerve dysfunction?

Answer 11

wrist drop

Question 12

what nerve is damaged in elbow fracture?

Answer 12

median nerve

Question 13

what is sensory & motor deficit if damaged median nerve?

Answer 13

motor = unable to flex muscles (as median supplies almost all flexors)
sensory = lateral aspect of palm

Question 14

what is median nerve motor supply?

Answer 14

• all muscles in forearm except (flexor carpi ulnaris and ulnar 1/2 flexor digitorum profundus (lots of u’s))
• in hand supplies LOAF = 1st 2 lumbricals, opponens pollicis, abductor pollicis brevis & flexor pollicis brevis (of thenar eminence)

Question 15

what are 3 hand presentations of median nerve palsy?

Answer 15

1. ape hand
2. hand of benediction
3. abnormal ok sign

Question 16

how does carpal tunnel syndrome present?

Answer 16

*reminder carpal tunnel syndrome = compression of tunnel & median nerve

wasting of thenar muscles, skin of palm usually spared as palmar cutaneous branch given off before median nerve goes through carpal tunnel therefore sensation to that part of palm is spared = classic sign of carpal tunnel

Question 17

what does ulnar nerve affected present as?

Answer 17

right hand has muscle wasting (particularly medial aspect)

Question 18

what does motor aspect ulnar nerve supply?

Answer 18

intrinsic muscles of hand & flexor carpi ulnaris & medial 1/2 of flexor digitorum profundus of forearm

Question 19

what is presentation if ulnar nerve damaged more proximally (at elbow)?

Answer 19

patient only be able to use flexor digitorum superficialis (since median nerve supplies)

Question 20

what is presentation if ulnar nerve damaged more distally (at wrist)?

Answer 20

flexor digitorum profundus already innervated so have full flexion in 4th & 5th digits but instead the intrinsic muscles of hand affected = patient can flex but more claw shape

“closer the paw, more the claw”