^aSpinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany

^bDepartment of Clinical Medicine, Danish Pain Research Center, Aarhus University, Aarhus, Denmark

^cIndiana Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery and Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN, USA

^*Corresponding author. Address: Spinal Cord Injury Center, Heidelberg University Hospital, Schlierbacher Landstrasse 200a, Heidelberg 69118, Germany. Tel.: +49-6221-5626322; fax: +49-6221-5626345. E-mail address: norbert.weidner@med.uni-heidelberg.de (N. Weidner).

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