Uncorrected Author Proof NeuroRehabilitation xx (20xx) x–xx DOI:10.3233/NRE-171456 IOS Press 1 Improved grasp function with transcranial direct current stimulation in chronic spinal cord injury 1 2 3 Mar Cortes a,b,c,∗ , Ana Heloisa Medeiros d , Aasta Gandhi a , Peter Lee a , Hermano Igo Krebs e , Gary Thickbroom a,b and Dylan Edwards a ,f ,g 4 5 a Burke Medical Research Institute, White Plains, NY, USA 6 b Department of Rehabilitation Medicine, Weill Cornell Medicine, New York, NY, USA 7 c Universitat de Barcelona, Barcelona, Spain 8 d Nervous System Electric Stimulation Laboratory, Rio de Janeiro State University, Brazil 9 e Newman Laboratory for Biomechanics and Human Rehabilitation, Massachusetts Institute of Technology (MIT), Boston, MT, USA 10 11 f Department of Neurology, Weill Cornell Medicine, New York, NY, USA 12 g School of Medical and Health sciences, Edith Cowan University, Joondalup, WA, Australia 13 Abstract. 14 BACKGROUND: Recovering hand function has important implications for improving independence of patients with tetraple- gia after traumatic spinal cord injury (SCI). Transcranial direct current stimulation (tDCS) is a noninvasive rehabilitation technique that has potential to improve motor function. 15 16 17 OBJECTIVE: To investigate the effects of one session of 1 mA, 2 mA, and sham anodal tDCS (a-tDCS) in the upper extremity (hand) motor performance (grasp and lease) in patients with chronic cervical SCI. 18 19 METHODS: Eleven participants with incomplete SCI were randomized to receive 20 minutes of 1 mA, 2 mA, or sham stimulation over the targeted motor cortex over three separated sessions. Hand motor performance was measured by the hand robot evaluation (kinematics) and the Box and Blocks (BB) test before and after the stimulation period. 20 21 22 RESULTS: A significant improvement on the grasp mean to peak speed ratio (GMP) was observed in the 2 mA group (pre: 0.38 ± 0.02; post: 0.43 ± 0.03; mean ± SEM; p = 0.031). There was no statistically significant difference in BB test results, however the 2mA intervention showed a positive trend for improvement. 23 24 25 CONCLUSIONS: A single session of 2 mA of a-tDCS showed gains in hand motor function in patients with chronic SCI that were not observed in functional clinical scales. The use of robotic kinematics showed promising results in assessing small changes in motor performance. Further studies are necessary to determine whether tDCS can translate into a long-term rehabilitative strategy for individuals with SCI. 26 27 28 29 Keywords: tDCS, hand robot, motor recovery, spinal cord injury 30 ∗ Address for correspondence: Mar Cortes, Human Spinal Cord Injury Repair Laboratory, Burke Medical Research Institute, 785 Mamaroneck Avenue, White Plains, NY 10605, USA. Tel.: +1 914 3683181; Fax: +1 914 597 2796; E-mail: mac2083@med.cornell.edu. 1. Introduction 31 The annual incidence of spinal cord injuries (SCI) 32 was approximately 12,500 new cases in the US, 33 and around 276,000 individuals were reported to 34 have disabilities due to SCI. SCI primarily affects 35 young males and incomplete tetraplegia is currently 36 1053-8135/17/$35.00 © 2017 – IOS Press and the authors. All rights reserved