A 30-year-old man with borderline tuberculoid leprosy presents with inability to extend his ring and little fingers, hyperextension at the metacarpophalangeal joints and flexion at the interphalangeal joints of the same hand. The nerve most likely damaged is:

• A Radial nerve at the spiral groove
• B Ulnar nerve behind the medial epicondyle ✓
• C Median nerve at the carpal tunnel
• D Common peroneal nerve at the fibular neck

Explanation

Ulnar nerve palsy in leprosy produces the classic main-en-griffe claw hand affecting the ring and little fingers, due to paralysis of the intrinsic muscles with unopposed long flexors and extensors. The ulnar nerve is palpable and vulnerable behind the medial epicondyle. Radial palsy gives wrist drop, median palsy affects thenar muscles and lateral digits, and peroneal palsy gives foot drop. Nerve examination at these palpable points is part of every leprosy assessment.

Reference: IAL Textbook of Leprosy, 2nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.