^a Washington University School of Medicine, St. Louis, MO, USA

^b Nerve Injury Unit, Departments of Anesthesiology, Neurology, and Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA

^c Department of Anesthesiology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Box 604, Rochester, NY 14642, USA

^∗Corresponding author. Tel.: +1-585-275-3524; fax: +1-585-473-5007

E-mail: robert_dworkin@urmc.rochester.edu