MSK

Question 1

What are some classic signs of ulnar nerve damage?

Answer 1

Damage at wrist

• ‘claw hand’ - hyperextension of the metacarpophalangeal joints and flexion at the distal and proximal interphalangeal joints of the 4th and 5th digits
• wasting and paralysis of intrinsic hand muscles (except lateral two lumbricals)
• wasting and paralysis of hypothenar muscles
• sensory loss to the medial 1 1/2 fingers (palmar and dorsal aspects)

Damage at elbow

• as above (however, ulnar paradox - clawing is more severe in distal lesions)
• radial deviation of wrist

Question 2

Which muscles are innervated by the deep peroneal nerve?

Answer 2

Tibialis anterior
Peroneus tertius
Extensor hallucis longus
Extensor digitorum longus
Extensor digitorum brevis

Question 3

Which nerve innervates the trapezius?

Answer 3

CN XI

Accessory