Movement Disorders USMLE Step 1 Practice Question
A 58-year-old woman presents with a 2-year history of progressive leg stiffness and mild weakness. Examination reveals hyperreflexia, extensor plantar responses bilaterally, and upper motor neuron signs without lower motor neuron findings. Vital signs: BP 128/82, HR 78, RR 16, Temp 37°C, SpO2 98%. Cognitive function and speech remain intact. MRI brain shows no focal lesions. CSF analysis is normal. She takes no medications. Which of the following is the most likely diagnosis?
Answer choices
- AFriedreich ataxia
- BPrimary lateral sclerosisCorrect answer
- CHereditary spastic paraplegia
- DSpinal muscular atrophy
- EAmyotrophic lateral sclerosis
- FTropical spastic paraparesis from HTLV-1
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