title: Mechanically Stable Intraspinal Microstimulation Implants for Human Translation.
abstract: The goal of this study was to develop stable intraspinal microstimulation (ISMS) implants for use in humans to restore standing and walking after spinal cord injury. ISMS electrically activates locomotor networks within the lumbar region of the spinal cord. In animals, ISMS produced better functional outcomes than those obtained by other interventions, and recent efforts have focused on translating this approach to humans. This study used domestic pigs to: (1) quantify the movements and length changes of the implant region of the spinal cord during spine flexion and extension movements; and (2) measure the forces leading to the dislodgement of the ISMS electrodes. The displacement of the spinal cord implant region was 5.66 ± 0.57 mm relative to the implant fixation point on the spine. The overall length change of the spinal cord implant region was 5.64 ± 0.59 mm. The electrode dislodgment forces were 60.9 ± 35.5 mN. Based on these results, six different coil types were fabricated and their strain relief capacity assessed. When interposed between the electrodes and the stimulator, five coil types successfully prevented the dislodgement of the electrodes. The results of this study will guide the design of mechanically stable ISMS implants for ultimate human use.
authors: Neuroscience and Mental Health Institute, University of Alberta, 5005 Katz Building, Edmonton, AB, T6G 2E1, Canada.|Alberta Innovates - Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), Edmonton, AB, Canada.
authors: Amirali
authors: A
authors: Toossi
authors: Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Alberta, Edmonton, AB, Canada.|Alberta Innovates - Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), Edmonton, AB, Canada.
authors: Dirk G
authors: DG
authors: Everaert
authors: Biomedical Instrumentation Lab, Department of Mechanical Engineering, University of Alberta, Edmonton, AB, Canada.|Alberta Innovates - Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), Edmonton, AB, Canada.
authors: Austin
authors: A
authors: Azar
authors: Biomedical Instrumentation Lab, Department of Mechanical Engineering, University of Alberta, Edmonton, AB, Canada.|Alberta Innovates - Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), Edmonton, AB, Canada.
authors: Christopher R
authors: CR
authors: Dennison
authors: Neuroscience and Mental Health Institute, University of Alberta, 5005 Katz Building, Edmonton, AB, T6G 2E1, Canada. vivian.mushahwar@ualberta.ca.|Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Alberta, Edmonton, AB, Canada. vivian.mushahwar@ualberta.ca.|Alberta Innovates - Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), Edmonton, AB, Canada. vivian.mushahwar@ualberta.ca.
authors: Vivian K
authors: VK
authors: Mushahwar
mesh_terms: D000818:Animals; D004599:Electric Stimulation Therapy / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D020007:Implants, Experimental; D008124:Locomotion; D013119:Spinal Cord Injuries / Q000503:physiopathology* / Q000628:therapy*; D013552:Swine
keywords: Coiled lead wire; Dislodgment forces; Intraspinal implant; Lumbar spine biomechanics; Strain relief