Gross Anatomy USMLE Step 1 Practice Question
A 36-year-old competitive cyclist presents with numbness affecting the palmar aspect of the fifth digit and weakness when abducting his fingers. Vital signs are normal (BP 118/76, HR 68, RR 14, Temp 98.6°F). Sensation is preserved over the dorsum of the hand. Electromyography shows denervation in intrinsic hand muscles supplied by one nerve. He denies cervical spine pain or upper arm symptoms. Compression of which of the following structures most likely explains his clinical findings?
Answer choices
- AUlnar nerve at Guyon canalCorrect answer
- BAnterior interosseous nerve
- CMedian nerve in carpal tunnel
- DPosterior interosseous nerve
- ERadial nerve
- FUlnar nerve at the cubital tunnel
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