Cited by 176Neuroscience and Neural EngineeringVagus Nerve Stimulation ResearchMuscle activation and electromyography studies

Long-term usability and bio-integration of polyimide-based intra-neural stimulating electrodes

Open access
Wurth, S., Capogrosso, M., Raspopovic, S., Gandar, J., Federici, G., Kinany, N., Cutrone, A., Piersigilli, A. +9 more·2017·Biomaterials

Abstract

Stimulation of peripheral nerves has transiently restored lost sensation and has the potential to alleviate motor deficits. However, incomplete characterization of the long-term usability and bio-integration of intra-neural implants has restricted their use for clinical applications. Here, we conducted a longitudinal assessment of the selectivity, stability, functionality, and biocompatibility of polyimide-based intra-neural implants that were inserted in the sciatic nerve of twenty-three healthy adult rats for up to six months. We found that the stimulation threshold and impedance of the electrodes increased moderately during the first four weeks after implantation, and then remained stable over the following five months. The time course of these adaptations correlated with the progressive development of a fibrotic capsule around the implants. The selectivity of the electrodes enabled the preferential recruitment of extensor and flexor muscles of the ankle. Despite the foreign body reaction, this selectivity remained stable over time. These functional properties supported the development of control algorithms that modulated the forces produced by ankle extensor and flexor muscles with high precision. The comprehensive characterization of the implant encapsulation revealed hyper-cellularity, increased microvascular density, Wallerian degeneration, and infiltration of macrophages within the endoneurial space early after implantation. Over time, the amount of macrophages markedly decreased, and a layer of multinucleated giant cells surrounded by a capsule of fibrotic tissue developed around the implant, causing an enlargement of the diameter of the nerve. However, the density of nerve fibers above and below the inserted implant remained unaffected. Upon removal of the implant, we did not detect alteration of skilled leg movements and only observed mild tissue reaction. Our study characterized the interplay between the development of foreign body responses and changes in the electrical properties of actively used intra-neural electrodes, highlighting functional stability of polyimide-based implants over more than six months. These results are essential for refining and validating these implants and open a realistic pathway for long-term clinical applications in humans.

Integrity signals

Registry

Crossref · 10.1016/j.biomaterials.2017.01.014

Cites

80 of 80 references verified0 citation errors · 0 not checkable

Statistics

Recomputing p-values needs the paper’s full text.

Claims the paper makes

We couldn’t retrieve this paper’s full text, so its claims and self-check weren’t run. The registry and citation checks still apply.

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • In a 6-month study of SELINE insertion into the sciatic nerve of rats, inflammatory response with swollen fibers was observed in the early phase after implantation, but it gradually resulted in capsule formation around the place of implantation, and all electrodes were functional at the end of the study.

    “A further study evaluated the results of SELINE insertion into the sciatic nerve of rats for 6 months [181]. Inflammatory response with swollen fibers was observed in the early phase after implantation, but it gradually resulted in capsule formation around the place of implantation, and all of the electrodes were functional at the end of the study.”
  • Selectivity, longevity, and long-term stability are integral for the establishment of long-lasting and functional sensory feedback for an amputee.

    “The selectivity, longevity, and long-term stability are absolutely an integral part for the establishment of long-lasting and functional sensory feedback for an amputee (Warren et al., 2016; Wurth et al., 2017).”

    From Selectivity and Longevity of Peripheral-Nerve and Machine Interfaces: A Review. (2017) · cites this paper as Wurth et al., 2017

  • The most recent study of Wurth et al. (2017) has demonstrated selectivity, stability, longevity, and biocompatibility of intra-neural type interfaces.

    “The most recent study of Wurth et al. (2017) has demonstrated the selectivity, stability, longevity, and biocompatibility of intra-neural type interfaces.”

    From Selectivity and Longevity of Peripheral-Nerve and Machine Interfaces: A Review. (2017) · cites this paper as Wurth et al. (2017)

Cites

Flagged first, then by citations

2 of the 82 references couldn’t be matched to a known paper.

Cited by

Sorted by citations

Authors
Wurth, S., Capogrosso, M., Raspopovic, S., Gandar, J., Federici, G., Kinany, N., Cutrone, A., Piersigilli, A., Pavlova, N., Guiet, R., Taverni, G., Rigosa, J., Shkorbatova, P., Navarro, X., Barraud, Q., Courtine, G., & Micera, S.
Affiliations
  • École Polytechnique Fédérale de Lausanne (CH)
  • Scuola Superiore Sant'Anna (IT)
  • University of Bern (CH)
  • Pavlov Institute of Physiology of the Russian Academy of Sciences (RU)
  • Scuola Internazionale Superiore di Studi Avanzati (IT)
  • Universitat Autònoma de Barcelona (ES)
Corresponding author
Micera, S.
Venue
Biomaterials
Publisher
Elsevier BV
Published
2017-04
Volume
122
Pages
114-129
ISSN
0142-9612 (ISSN-L)
OpenAlex
W2578816048
Cited by
176
References
82
Citations by year
2026: 16 · 2025: 16 · 2024: 20 · 2023: 18 · 2022: 20 · 2021: 29 · 2020: 16 · 2019: 19 · 2018: 15 · 2017: 7
FWCI
7.65
Type
journal article
Language
en
Open access
Locations
  • Biomaterials (acceptedVersion)
  • PubMed (publishedVersion)
  • Infoscience (Ecole Polytechnique Fédérale de Lausanne) (submittedVersion)
  • Infoscience (Ecole Polytechnique Fédérale de Lausanne) (submittedVersion, cc-by-nc-nd)
  • Archive ouverte UNIGE (University of Geneva) (submittedVersion, cc-by)
  • CINECA IRIS Institutional Research Information System (Sant'Anna School of Advanced Studies) (submittedVersion)
Funders
  • Wyss Center for Bio and Neuroengineering
  • European Commission (FP7-611687)
  • European Research Council (ERC 261247)
  • École Polytechnique Fédérale de Lausanne
  • International Foundation for Research in Paraplegia
  • Fondation Bertarelli
  • Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (205321_170032, 315230_149902)
Topics
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neuroscience and Neural Engineering
  • Life Sciences › Neuroscience › Neurology › Vagus Nerve Stimulation Research
  • Physical Sciences › Engineering › Biomedical Engineering › Muscle activation and electromyography studies
Keywords
polyimide electrodes, peripheral nerve stimulation, sciatic nerve, long-term biocompatibility, foreign body reaction, fibrotic capsule, electrical impedance, stimulation threshold, Wallerian degeneration, macrophage infiltration, multinucleated giant cells, nerve regeneration, implant encapsulation
MeSH terms
Animals, Biocompatible Materials, Electric Stimulation, Equipment Design, Female, Longitudinal Studies, Microelectrodes, Rats, Inbred Lew, Resins, Synthetic, Sciatic Nerve, Treatment Outcome, Equipment Failure Analysis, Rats, Implantable Neurostimulators

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review