27th June 2023

A 45-year-old man has difficulty walking for several months. On examination, he has bilateral ptosis, weakness of the proximal upper limbs

A 45-year-old man has difficulty walking for several months. On examination, he has bilateral ptosis, weakness of the proximal upper limbs and winging of the scapular, he has bilateral foot drop with distal wasting and pes cavus. There is absence of ankle jerks.

Select the SINGLE most likely diagnosis from the list below. Select ONE option only.