Neuroanatomy USMLE Step 1 Practice Question
A 45-year-old garbage collector has severe neck pain and weakness in his left upper extremity. He has gotten no relief from over-the-counter medications. He denies any history of trauma. On examination, the patient is thin and walks with his neck tilted to the left side. The patient has limited neck flexion and extension secondary to pain. The patient has a normal motor and sensory examination of all extremities, with the exception of the left upper extremity. His left radial forearm and thumb are numb to the touch (decreased sensation to light touch). The patient has a decreased brachioradialis reflex and slight weakness of his wrist extensors. Plain radiographs appear normal. Which of the following is the most likely diagnosis?
Answer choices
- ACompression of his left thoracic first nerve root (T1)
- BCompression of his left C6 nerve rootCorrect answer
- CA tumor in his sacral spine
- DCompression of his right T1 nerve root
- EA tumor in his lumbar spine
- FPosterior interosseous nerve entrapment
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