Abstract
Limb loss causes severe sensorimotor deficits and often necessitates prosthetic devices, particularly in lower-limb amputees. Although direct neural recording from residual nerves offers a biomimetic route for prosthetic control, low signal amplitudes and challenges in nerve interfacing have limited adoption. Intraneural multichannel electrodes provide a potential solution by enabling access to motor signals from muscles lost after amputation. Here, we report intraneural recordings from two transfemoral amputees using transversal intrafascicular multichannel electrodes implanted in distal branches of the sciatic nerve. We identified multiunit activity associated with volitional phantom movements of the knee, ankle, and toes, exhibiting joint- and direction-specific modulation distributed across electrodes. A Spiking Neural Network–based decoder outperformed conventional methods in predicting attempted movements, with further gains achieved by integrating intraneural and intermuscular signals. Motor and sensory maps showed minimal overlap, indicating early segregation within the sciatic nerve. These findings pave the way for bidirectional, neurally-controlled prosthetic systems.
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Data availability
All data supporting the findings of this study are available within the article and its Supplementary files. Individual de-identified participant data experimental data supporting the findings are immediately and indefinitely available at https://github.com/rossicecilia/intraneural_phantom_leg.git for anyone who wishes to access the data for any purpose. Source data are also provided in this paper. Any additional requests for information can be directed to and will be fulfilled by the corresponding authors. Protocol for human clinical trials is given as part of the reporting summary. Source data are provided with this paper.
Code availability
Custom code used for analysis is publicly available through https://github.com/rossicecilia/intraneural_phantom_leg.git. Code used for data collection can be made available upon request to the study PIs.
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Acknowledgements
The authors are deeply grateful to the three subjects who freely donated months of their life for the advancement of knowledge and for a better future for leg amputees. The funder had no role in the experimental design, analysis, or manuscript preparation or submission. All authors had complete access to the data. All authors authorized the submission of the manuscript, but the final submission decision was made by the corresponding authors. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (FeelAgain grant agreement no. 759998, S.R.).
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C.R. analyzed the neural data, implemented and tested the SNN-based motor decoders, prepared the figures and wrote the paper; T.S. and P.C. developed the TIME and delivered technical assistance for the human implantation and explanation procedures and reviewed the manuscript; M.B. performed the human surgeries and was responsible for all the clinical aspects of the human study; S.R. designed the study, performed and supervised the human experiments and reviewed the manuscript; E.D., supervised all the analyses, and wrote the paper; G.V. developed the recording software for human experiments, performed the human experiments, supervised all the analyses, prepared the figures and wrote the paper. All authors edited and proofread the manuscript.
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G.V. holds shares of “MYNERVA AG”, a start-up company dealing with the potential commercialization of noninvasive stimulating wearable for treating neuropathic pain. G.V. serves as a consultant for NeuroOne Medical Technologies Corporation (USA). The other authors do not have anything to disclose.
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Rossi, C., Bumbasirevic, M., Čvančara, P. et al. Decoding phantom limb movements from intraneural recordings. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69297-0
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DOI: https://doi.org/10.1038/s41467-026-69297-0
