Restoring dexterous hand control is critical for people with paralysis. Approaches based on surface or intramuscular stimulation provide limited finger control, generate insufficient force to recover functional movements, and require numerous electrodes. Here, we show that intrafascicular peripheral electrodes could produce functional grasps and sustained forces in three monkeys. We designed an intrafascicular implantable electrode targeting the motor fibers of the median and radial nerves. Our interface selectively and reliably activated extrinsic and intrinsic hand muscles, generating multiple functional grips, hand opening, and sustained contraction forces for up to 2 months. We extended those results to a behaving monkey with transient hand paralysis and used intracortical signals to control simple stimulation protocols that enabled this animal to perform a functional grasping task. Our findings show that just two intrafascicular electrodes can generate a rich portfolio of dexterous and functional hand movements with important implications for clinical applicability.

中文翻译：

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束内周围神经刺激在灵长类动物中产生精细的功能性手部运动

恢复灵巧的手部控制对瘫痪患者至关重要。基于表面或肌肉内刺激的方法提供有限的手指控制，产生的力量不足以恢复功能性运动，并且需要大量电极。在这里，我们表明束内外围电极可以在三只猴子身上产生功能性抓握和持续力。我们设计了一种针对正中神经和桡神经运动纤维的束内植入式电极。我们的界面选择性且可靠地激活外在和内在手部肌肉，产生多种功能性抓握、手张开和长达 2 个月的持续收缩力。我们将这些结果扩展到一只表现出短暂手麻痹的猴子，并使用皮层内信号来控制简单的刺激方案，使这只动物能够执行功能性抓取任务。我们的研究结果表明，仅两个束内电极就可以产生丰富的灵巧和功能性手部动作组合，对临床适用性具有重要意义。