Past Projects‎ > ‎

PSF Project

There are over 1.7 million people within the United States currently suffering from some type of limb loss, and this number continues to grow by 185,000 each year.  Typical upper extremity replacement limbs are passive prosthetic devices and provide little functional recovery beyond basic grasping.  Newer prostheses that add additional control through using muscle activity of the patient’s remaining muscle groups increase the utility of these replacement limbs.  The current state of the art treatment allows subjects to have the greatest restoration of function through targeted reinnervation of muscle groups using nerve from the amputated limb.  However, these devices have limited control options for prostheses with multiple degrees of freedom and are generally difficult to master.

We have developed a regenerative peripheral nerve interface (RPNI) that creates a biologically robust and functional connection to the nerve in an amputated limb through the use of a graft of free muscle tissue. The graft is then sutured to the severed residual nerve, and electrodes are affixed allowing signals to be recorded from the nerve (epineural electrode), or the muscle (epimysial electrode). These electrophysiological signals are then used for control of a replacement robotic arm.

We propose to quantify the effect of neuromuscular amplification in regenerative peripheral nerve interfaces.  Using a rodent model developed within our research group, we will quantify the information content that can be recorded by using a neuromuscular “amplifier”.  Nerve signals will be sampled after they have been “amplified” by the muscle, thereby providing a higher signal-to-noise ratio without signal loss from electrode encapsulation and tissue trauma from direct epineural electrode placement.  Further, the use of epimysial electrodes should increase the overall long-term stability of the interface, compared to current methods utilizing penetrating electrodes either in the nerve or muscle.