TY - JOUR T1 - Epidural Electrical Stimulation of the Cervical Dorsal Roots Restores Voluntary Upper Limb Control in Paralyzed Monkeys JF - bioRxiv DO - 10.1101/2020.11.13.379750 SP - 2020.11.13.379750 AU - B. Barra AU - S. Conti AU - M.G. Perich AU - K. Zhuang AU - G. Schiavone AU - F. Fallegger AU - K. Galan AU - N. D. James AU - Q. Barraud AU - M. Delacombaz AU - M. Kaeser AU - E. M. Rouiller AU - T. Milekovic AU - S. Lacour AU - J. Bloch AU - G. Courtine AU - M. Capogrosso Y1 - 2021/01/01 UR - http://biorxiv.org/content/early/2021/11/08/2020.11.13.379750.abstract N2 - Recovering arm control is a top priority for people with paralysis. Unfortunately, the complexity of the neural mechanisms underlying arm control practically limited the effectiveness of neurotechnology approaches. Here, we exploited the neural function of surviving spinal circuits to restore voluntary arm and hand control in three monkeys with spinal cord injury using spinal cord stimulation. Our neural interface leverages the functional organization of the dorsal roots to convey artificial excitation via electrical stimulation to relevant spinal segments at appropriate movement phases. Stimulation bursts targeting specific spinal segments produced sustained arm movements enabling monkeys with arm paralysis to perform an unconstrained reach-and-grasp task. Stimulation specifically improved strength, task performances and movement quality. Electrophysiology suggested that residual descending inputs were necessary to produce coordinated movements. The efficacy and reliability of our approach hold realistic promises of clinical translation.Competing Interest StatementG.Courtine., J.Bloch., S.Lacour., M.Capogrosso., B.Barra. and K.Zhuang. hold various patents in relation to the present work. G.Courtine., S.Lacour. and J.Bloch. are founders and shareholders of GTX medical, a company developing an EES-based therapy to restore movement after spinal cord injury. ER -