Neuromuscular Disorders USMLE Step 1 Practice Question
A 15-year-old boy presents with recurrent ankle sprains and progressive difficulty running. Vital signs are normal (BP 118/76, HR 82, RR 16, Temp 37°C, SpO2 98%). Physical examination reveals pes cavus deformity, distal lower extremity weakness, and decreased vibration sensation in both feet with absent ankle reflexes. Nerve conduction studies show slowed conduction velocities in lower extremities. His father reports identical symptoms. Which of the following is the most likely diagnosis?
Answer choices
- AMyasthenia gravis
- BAmyotrophic lateral sclerosis
- CCharcot Marie Tooth diseaseCorrect answer
- DSpinal muscular atrophy
- EGuillain Barré syndrome
- FFriedreich ataxia
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