Peripheral Mononeuropathy - Ulnar Nerve Palsy

Question 1

Aetiology of Ulnar Nerve Palsy.

Answer 1

1. Trauma at Medial Epicondyle.
2. Compression in Cubital Tunnel.
3. Lacerations to Anterior Wrist (Guyon’s Canal)

Question 2

Clinical Features of Ulnar Nerve Palsy.

Answer 2

1. Paralysis of Interossei - No Abduction or Adduction of Fingers.
2. Paralysis/Wasting of Medial 2 Lumbricals and Hypothenar Muscles : Impaired Movement of 4th and 5th Digits.
3. Impaired Adduction of Thumb : Positive Froment’s Sign (Paralysis of Adductor
   Policies).
4. Claw Hand - Hyperextension of MCP Joints and Flexion of DIP and PIP of 4th and 5th Joints.

Question 3

What is Cubital Tunnel Syndrome?

Answer 3

Compression of Ulnar Nerve as it passes through Cubital Tunnel.

Question 4

Clinical Features of Cubital Tunnel Syndrome (3).

Answer 4

1. Tingling + Numbness of 4th and 5th Finger.
2. Weakness and Muscle Wasting.
3. Pain Worse on Leaning on Elbow.

Question 5

What is the Ulnar Paradox?

Answer 5

Greater clawing in the hand when there is a lesion at the wrist compared to the elbow - higher lesions cause weakness of flexor digitorum of Flexor Digitorum Profundus.