ABEM (EDX)

Practice session

A 19-year-old college student presents with acute right arm weakness and severe shoulder pain 10 days after an upper respiratory illness. Examination shows weakness of shoulder abduction and external rotation. Needle EMG shows fibrillations and reduced recruitment in deltoid, supraspinatus, and infraspinatus, but normal studies in biceps and brachioradialis. Sensory studies are normal. What is the most likely diagnosis?

Loading your practice session…