Chronic, Battery-Free, Fully Implantable Multimodal Spinal Cord Stimulator for Pain Modulation in Small Animal Models.

Spinal cord stimulation (SCS) for chronic pain management is an invasive therapy involving surgical implantation of electrodes into spinal epidural space. While the clinical value and mechanistic action of the therapy is debated considerably in recent years, preclinical chronic studies employing rodent models can provide invaluable insights regarding the balance between efficacy and complications as well as mechanistic understanding of SCS therapy. However, current rodent compatible devices require tethered power delivery or bulky batteries, severely limiting the ability to probe long-term efficacy of SCS therapy. This work introduces a tether-free, small-footprint, fully implantable, battery-free SCS device compatible with rodent models, capable of delivering electrical stimulation to the spinal cord at a wide range of frequency, amplitude, and period via wireless communication adjustable on-demand without direct interaction with the animal. The presented device features capabilities of clinical SCS devices, with materials and processes amendable to scalable fabrication at a cost suitable for one-time use enabling high N studies. In this proof of concept, the implantable device serves to assess therapeutic efficacy of various clinically relevant SCS paradigms in alleviating neuropathic pain. This technology offers chronic stability and the potential to serve as the foundation for future research into the development of SCS therapeutic systems.