However, at postoperative day 2, he started to develop bilateral ankle dorsiflexor weakness and at day 3 he had no ankle dorsiflexion on the right and marked weakness on the left. He was referred for electrodiagnostic studies on postoperative day 3 to rule out bilateral peroneal palsy or possibly a spinal cord or root lesion. Prior to continuing, please develop a differential diagnosis and list each diagnosis in order of likelihood. He reports numbness in the feet bilaterally. If necessary, please revise your differential diagnosis based on the additional clinical history.
Sensation is reduced to pinprick and light touch diffusely in the feet, but is normal proximally.
Upper limb sensation is also normal. At this point, review your differential diagnosis and revise as appropriate. Determine a final working differential diagnosis from which to design your electrodiagnostic study. Formulate your approach to the electrodiagnostic study.