Neuromuscular Disorders USMLE Step 1 Practice Question
A 33-year-old man with a history of heavy alcohol use falls asleep in a chair with his arm draped over the backrest. Upon awakening, he is unable to extend his wrist and fingers. Physical examination reveals decreased sensation over the dorsal first web space and normal biceps strength. His vital signs are stable: BP 128/82 mmHg, HR 76/min, RR 14/min. Nerve conduction studies show slowed conduction velocity in the radial nerve distribution. Which nerve is most likely injured?
Answer choices
- AMusculocutaneous nerve
- BMedian nerve
- CUlnar nerve
- DAxillary nerve
- ERadial nerveCorrect answer
- FPosterior interosseous nerve
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