UE Nerves

Question 1

Axillary

Answer 1

C5-C6

CAUSE OF INJURY
Fractured surgical neck of humerus
anterior dislocation of humerus

PRESENTATION

• Flattened deltoid
• Loss of arm abduction at shoulder (> 15 degrees)
• Loss of sensation over deltoid muscle and lateral arm

Question 2

Musculocutaneous

Answer 2

C5-C7

CAUSE OF INJURY
Upper trunk compression

PRESENTATION

• Loss of forearm flexion and supination
• Loss of sensation over lateral forearm

Question 3

Radial

Answer 3

C5-T1

CAUSE OF INJURY
-Midshaft fracture of humerus
-compression of axilla, eg, due to crutches or sleeping with arm
over chair (“Saturday night palsy”)

PRESENTATION
-Wrist drop
- DEC grip strength
-Loss of sensation over posterior arm/forearm and dorsal hand

Question 4

Median

Answer 4

C5-T1

CAUSE OF INJURY

• Supracondylar fracture of humerus (proximal lesion)
• carpal tunnel syndrome and wrist laceration (distal lesion)

PRESENTATION
-“Ape hand” and “Pope’s blessing”
-Loss of wrist flexion, flexion of lateral fingers, thumb opposition, lumbricals of 2nd and 3rd digits
-Loss of sensation over thenar eminence and dorsal and palmar aspects of lateral 31⁄2 fingers
with proximal lesion

Question 5

Ulnar

Answer 5

C8-T1

CAUSE OF INJURY

• Fracture of medial epicondyle of humerus “funny bone” (proximal lesion)
• fractured hook of hamate (distal lesion)

PRESENTATION
-“Ulnar claw” on digit extension
-Radial deviation of wrist upon flexion (proximal lesion)
-Loss of wrist flexion, flexion of medial fingers, abduction and adduction of fingers (interossei),
actions of medial 2 lumbrical muscles
-Loss of sensation over medial 11/2 fingers including hypothenar eminence

Question 6

Recurrent branch of median nerve

Answer 6

C5-T1

CAUSE OF INJURY
Superficial laceration of palm

PRESENTATION

• “Ape hand”
• Loss of thenar muscle group: opposition, abduction, and flexion of thumb
• No loss of sensation