SCI Program

Hand Grasp and Release for C5-C6 Tetraplegia

Participants with C5/C6 tetraplegia utilize implanted FES systems to facilitate return of basic hand function.

General Information on this clinical study

Principal Investigators: P. Hunter Peckham, Ph.D. and Kevin Kilgore, Ph.D.

Clinical Coordinator: Carol Sams, N.P.

Contact Number: 216-778-3480

Contact Email: carol.sams@va.gov

Program Title: Hand Grasp and Release for C5/C6

Purpose

Utilizing an implanted stimulator, this program explores achieving hand function for individuals with C5/C6 tetraplegia.

Program Description

The goal of this research project is to expand the capabilities of our implantable stimulator-telemeter platform of neuroprostheses, allowing it to be readily adapted for a large number of clinical applications, including standing and walking, grasp and proximal arm control, bladder and bowel function, and respiratory pacing. Specifically, we will expand our current capabilities by delivering a total of 16 channels of stimulation at levels safe for either nerve- or muscle-based electrodes on any output channel, and providing feedback information through sensors integrated into the implant package itself.

These advances will allow nerve- or muscle-based electrodes to be combined in any possible configuration under software control to tailor the neuroprosthetic system for numerous user-specific applications allowing advanced control of the resulting movements without additional surgery or cumbersome and unreliable external cabling. In this project, we will design, develop, and fully test a general-purpose neuroprosthetic system consisting of a 16 channel implantable stimulator (IST-16) and a universal external control unit (UECU). The implantable stimulator will be capable of both muscle-based and nerve-based stimulation on any channel, and capable of sensing multi-axis accelerations, monitoring its own status and telemetering diagnostic information to the universal external control unit to insure fail-safe operation. The universal external control unit will power and control the implanted device, and will be in a small, lightweight and wearable package.

During the past year, we have tested new circuitry that allows the same output stage to be used to produce stimulus pulses for both nerve- and muscle-based electrodes. This circuitry prevents currents from passing through nerve-based electrodes during stimulus delivery, and has now been tested in-vivo. The IST-16 circuit design incorporating this new feature is now nearly complete and ready for fabrication of prototype devices. Also, during the past year, the prototypes of the external control unit have been tested clinically for a variety of applications.We are now preparing for an initial production run of these units, including units to be used with the IST-16 implantable system. During the next year, we will demonstrate clinical feasibility of this system by implementing advanced standing and walking systems in one human subject with motor complete thoracic level paraplegia, and evaluate the functional impact and technical performance of the implant, particularly documenting the improved function provided by the 16-channel neuroprosthetic system.