Case 310.

/μL) levels. Absence of coagulopathy was demonstrated by normal coagulation values (international normalized ratio, 1.19; reference value, 0.80-1.25; activated partial thromboplastin time ratio, 0.88 second; reference range, 0.79-1.27 seconds). Electroneurography showed marked hypoevocable F response in the right tibia. Electromyography indicated severe reduction of muscle recruitment pertaining to right L4, L5, and S1 nerve territory and, to a lesser extent, of muscles pertaining to L3 territory bilaterally in the absence of spontaneous denervation. Unenhanced CT (Fig 1) and contrast-enhanced MRI of the lumbosacral spine were performed (Figs 2, 3).