PROJECT SUMMARY The objective of this Phase I SBIR is to develop a spinal fusion implant with embedded biomechanically powered sensor. Evoke Medical’s core technology is to create human-powered implantable devices that utilize piezoelectric materials to generate load-induced power. That power can then be used for various purposes: electrical stimulation of bone growth and/or load-sensing to track fusion progression. Through our current Phase II project, a fully integrated piezoelectric transforaminal lumbar interbody fusion (TLIF) implant was developed with embedded power generator and miniaturized circuitry for signal conditioning. In this TLIF implant, lower impedance piezoelectric materials were used to generate power for mechanically synced direct current (DC) electrical stimulation delivered to an electrode on the implant surface for the purposes of enhancing bone growth. No batteries are used in any Evoke Medical implant as all energy is biomechanically induced by human motion. Our preliminary work has also shown that a piezoelectric interbody implant can act as a sensor and distinguish between different applied physiological loads that correlate to fusion progression. In other industries, piezoelectric materials are often used as load sensors. In situ, mechanical loads applied to the piezoelectric device generate proportional electrical voltages that can be translated back to quantify the applied load on the device. Evoke Medical will use this inherent ability of piezoelectric materials to characterize the change in load environment within the disc space, and subsequently provide objective data to the clinician and patient to inform post-operative outcomes and treatment decisions. In spinal fusion, the load on the implant is highest when the device is first implanted and there is no bony fusion mass around and throughout the implant. As fusion progresses, the load on the implant is reduced according to the fusion grade achieved due to the increased surface area and stiffness of the growing bone structure. In this proposal, we will prove that a custom piezogenerator embedded in a spinal fusion implant with the associated circuit hardware and data acquisition software can collect, store, and wirelessly transmit changes in load within the interbody space. These changes can then be related back to fusion progression and other post-operative outcomes. Evoke Medical has already developed cost-effective manufacturing methods and demonstration of safety and efficacy of the stimulating aspect of the piezoelectric TLIF that is moving forward in the commercialization process through a DeNovo regulatory strategy. In these verification tests, we have also proven that we can successfully harvest patient motion and convert that to usable power under physiological loading conditions. By developing the load sensing aspect of the TLIF implant now, Evoke Medical will be able to jumpstart our capabilities to provide patients with biofeedback on how their impl...