title: Development of a neurotechnological system for relieving phantom limb pain using transverse intrafascicular electrodes (TIME).
abstract: Phantom limb pain (PLP) is a chronic condition that develops in the majority of amputees. The underlying mechanisms are not completely understood, and thus, no treatment is fully effective. Based on recent studies, we hypothesize that electrical stimulation of afferent nerves might alleviate PLP by giving sensory input to the patient if nerve fibers can be activated selectively. The critical component in this scheme is the implantable electrode structure. We present a review of a novel electrode concept to distribute highly selective electrode contacts over the complete cross section of a peripheral nerve to create a distributed activation of small nerve fiber ensembles at the fascicular level, the transverse intrafascicular multichannel nerve electrode (TIME). The acute and chronic implantations in a small animal model exhibited a good surface and structural biocompatibility as well as excellent selectivity. Implantation studies on large animal models that are closer to human nerve size and anatomical complexity have also been conducted. They proved implant stability and the ability to selectively activate nerve fascicles in a limited proximity to the implant. These encouraging results have opened the way forward for human clinical trials in amputees to investigate the effect of selective electrical stimulation on PLP.
authors.affiliation: Laboratory for Biomedical Microtechnology, IMTEK-Department of Microsystems Engineering and Bernstein Center Freiburg, University of Freiburg, Georges-Koehler-Allee 102, D-79110 Freiburg, Germany. stieglitz@imtek.uni-freiburg.de
authors.forename: Thomas
authors.initials: T
authors.lastname: Stieglitz
authors.forename: Tim
authors.initials: T
authors.lastname: Boretius
authors.forename: Xavier
authors.initials: X
authors.lastname: Navarro
authors.forename: Jordi
authors.initials: J
authors.lastname: Badia
authors.forename: David
authors.initials: D
authors.lastname: Guiraud
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Divoux
authors.forename: Silvestro
authors.initials: S
authors.lastname: Micera
authors.forename: Paolo Maria
authors.initials: PM
authors.lastname: Rossini
authors.forename: Ken
authors.initials: K
authors.lastname: Yoshida
authors.forename: Kristian R
authors.initials: KR
authors.lastname: Harreby
authors.forename: Aritra
authors.initials: A
authors.lastname: Kundu
authors.forename: Winnie
authors.initials: W
authors.lastname: Jensen
mesh_terms: D000818:Animals; D004599:Electric Stimulation Therapy / Q000295:instrumentation*; D004567:Electrodes, Implanted; D004867:Equipment Design; D019544:Equipment Failure Analysis; D051379:Mice; D010525:Peripheral Nerves / Q000503:physiopathology*; D010591:Phantom Limb / Q000503:physiopathology* / Q000517:prevention & control* / Q000534:rehabilitation; D016896:Treatment Outcome