Becerra Fajardo, LauraMinguillon, JesusKrob, Marc OliverRodrigues, CamilaGonzález Sánchez, MiguelMegía-García, ÁlvaroRedondo Galán, CarolinaGutiérrez Henares, FranciscoComerma-Montells, AlbertDel-Alma, Antonio J.Gil-Agudo, ÁngelGrandas, FranciscoSchneider-Ickert, AndreasBarroso, Filipe O.Ivorra Cano, Antoni, 1974-2024-01-292024-01-292024Becerra-Fajardo L, Minguillon J, Krob MO, Rodrigues C, González-Sánchez M, Megía-García Á, et al. First-in-human demonstration of floating EMG sensors and stimulators wirelessly powered and operated by volume conduction. J Neuroeng Rehabil. 2024 Jan 3;21(1):4. DOI: 10.1186/s12984-023-01295-51743-0003http://hdl.handle.net/10230/58868Background: Recently we reported the design and evaluation of floating semi-implantable devices that receive power from and bidirectionally communicate with an external system using coupling by volume conduction. The approach, of which the semi-implantable devices are proof-of-concept prototypes, may overcome some limitations presented by existing neuroprostheses, especially those related to implant size and deployment, as the implants avoid bulky components and can be developed as threadlike devices. Here, it is reported the first-in-human acute demonstration of these devices for electromyography (EMG) sensing and electrical stimulation. Methods: A proof-of-concept device, consisting of implantable thin-film electrodes and a nonimplantable miniature electronic circuit connected to them, was deployed in the upper or lower limb of six healthy participants. Two external electrodes were strapped around the limb and were connected to the external system which delivered high frequency current bursts. Within these bursts, 13 commands were modulated to communicate with the implant. Results: Four devices were deployed in the biceps brachii and the gastrocnemius medialis muscles, and the external system was able to power and communicate with them. Limitations regarding insertion and communication speed are reported. Sensing and stimulation parameters were configured from the external system. In one participant, electrical stimulation and EMG acquisition assays were performed, demonstrating the feasibility of the approach to power and communicate with the floating device. Conclusions: This is the first-in-human demonstration of EMG sensors and electrical stimulators powered and operated by volume conduction. These proof-of-concept devices can be miniaturized using current microelectronic technologies, enabling fully implantable networked neuroprosthetics.application/pdfeng© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.info:eu-repo/semantics/articlehttp://dx.doi.org/10.1186/s12984-023-01295-5AIMDsBidirectional communicationsElectrical stimulationElectromyographyHuman validationNeuroprosthesesSemi-implantable devicesSensorVolume conductionWireless power transferinfo:eu-repo/semantics/openAccess