It is proposed that IntraFascicular, Multielectrode Stimulation (IFMS), mediated by high electrode count microelectrode arrays, implanted intrafascicularly into peripheral nerves can significantly improve restoration of motion in paraplegic patients over that produced with cuff or epimysial electrodes. This proposition is based on the following advantages of IFMS. 1) Fewer implant sites are required to electrically activate many more muscles, greatly simplifying surgical procedures. 2) Because the tips of the implanted electrodes are in close proximity to the motor neurons, electrical currents required for stimulation are very low. 3) Each muscle is accessed by many individual electrodes, allowing more selective stimulation of individual muscles with low stimulation currents. 4) Each implanted electrode accesses an independent set of motor units which allows a more physiological recruitment of muscle force. 5) Access to independent motor units allows one to use more physiological stimulation protocols that greatly reduce muscle fatigue. Work is proposed to exploit these benefits of IFMS and to investigate new challenges encountered during IFMS restoration of stance behaviors in decerebrate cats and arising from the unprecedented access to the distal musculature provided by the Utah Slanted Electrode Array (USEA). The work will be performed in a hierarchical series of experiments and conducted within the context of a biomechanically realistic 3-D musculoskeletal model of the cat hind limb that will be developed in Specific Aim 1. The model will help specify which muscles to activate, and the forces in these muscles to achieve stance behaviors.
Specific Aim 2 will develop stimulation algorithms that provide load-relevant, ripple-free, fatigue-resistant muscle forces.
Specific Aim 3 will optimize the implantation sites of USEA's to access the maximum number of hip, knee, and ankle extensor muscles while providing ease of surgical implantation procedures.
Specific Aim 4 will extend the isometric muscle force experiments (SA2-3) to understanding the dynamics of IFMS induced muscle contraction during physiological muscle trajectories.
Specific Aim 5 will investigate the interactions that occur when torques are produced by multiple muscles at each joint.
Specific Aim 6 will achieve the behaviorally relevant sit-to-stand and stance tasks in the acutely paralyzed cat model. These experiments will demonstrate the advantages of IFMS mediated by USEA's implanted in the cat femoral and sciatic nerves in achieving a set of multi-joint, multi-muscle, multi-limb motor behaviors relevant to the paraplegic population, and will form a prelude to future experiments on IFMS evoked gait in cats, and eventually, in humans.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS039677-07
Application #
7256366
Study Section
Special Emphasis Panel (ZRG1-MDCN-C (55))
Program Officer
Pancrazio, Joseph J
Project Start
2000-01-28
Project End
2009-04-30
Budget Start
2007-05-01
Budget End
2008-04-30
Support Year
7
Fiscal Year
2007
Total Cost
$413,998
Indirect Cost
Name
University of Utah
Department
Biomedical Engineering
Type
Schools of Engineering
DUNS #
009095365
City
Salt Lake City
State
UT
Country
United States
Zip Code
84112
Normann, R A; Dowden, B R; Frankel, M A et al. (2012) Coordinated, multi-joint, fatigue-resistant feline stance produced with intrafascicular hind limb nerve stimulation. J Neural Eng 9:026019
Dowden, B R; Frankel, M A; Normann, R A et al. (2012) Non-invasive method for selection of electrodes and stimulus parameters for FES applications with intrafascicular arrays. J Neural Eng 9:016006
Frankel, Mitchell A; Dowden, Brett R; Mathews, V John et al. (2011) Multiple-input single-output closed-loop isometric force control using asynchronous intrafascicular multi-electrode stimulation. IEEE Trans Neural Syst Rehabil Eng 19:325-32
MacFadden, Lisa N; Brown, Nicholas A T (2010) The influence of modeling separate neuromuscular compartments on the force and moment generating capacities of muscles of the feline hindlimb. J Biomech Eng 132:081003
Negi, Sandeep; Bhandari, Rajmohan; Rieth, Loren et al. (2010) Neural electrode degradation from continuous electrical stimulation: comparison of sputtered and activated iridium oxide. J Neurosci Methods 186:8-17
McDaniel, J; Elmer, S J; Martin, J C (2010) Limitations of relaxation kinetics on muscular work. Acta Physiol (Oxf) 198:191-8
McDaniel, John; Elmer, Steven J; Martin, James C (2010) The effect of shortening history on isometric and dynamic muscle function. J Biomech 43:606-11
Wilder, Andrew M; Hiatt, Scott D; Dowden, Brett R et al. (2009) Automated stimulus-response mapping of high-electrode-count neural implants. IEEE Trans Neural Syst Rehabil Eng 17:504-11
Gunalan, Kabilar; Warren, David J; Perry, Justin D et al. (2009) An automated system for measuring tip impedance and among-electrode shunting in high-electrode count microelectrode arrays. J Neurosci Methods 178:263-9
Dowden, Brett R; Wilder, Andrew M; Hiatt, Scott D et al. (2009) Selective and graded recruitment of cat hamstring muscles with intrafascicular stimulation. IEEE Trans Neural Syst Rehabil Eng 17:545-52

Showing the most recent 10 out of 16 publications