CLEVELAND, Ohio — A collaborative effort between Case Western Reserve University (CWRU) and the Louis Stokes Cleveland VA Medical Center has secured a substantial $9.9 million grant from the U.S. Department of Defense. This funding will support the clinical trial of an innovative prosthetic hand that provides amputees with a sense of touch, a breakthrough in the field of neuroprosthetics.
The prosthetic device, known as iSens (implanted Somatosensory Electrical Neurostimulation and Sensing system), utilizes implanted electrodes that detect muscle movements in the residual limb. This technology enables users to control the hand while simultaneously stimulating nerves to transmit sensory feedback from the fingertips back to the brain. According to CWRU, the system operates through a Bluetooth connection between an implanted neural control device and the prosthesis.
Groundbreaking Research and Development
The iSens neuroprosthesis builds on previous research funded by an eight-year, $14 million grant from the Defense Advanced Research Projects Agency (DARPA), which will conclude in 2023. CWRU researchers are set to begin enrolling participants for the trial in early 2024. Individuals interested in participating can reach out to the study coordinator via email at [email protected].
Leading the research is Emily Graczyk, an assistant professor of biomedical engineering at CWRU and an investigator at the Cleveland VA. Graczyk emphasizes the importance of advanced prosthetic technologies for individuals with upper-limb loss. “People with upper-limb loss deserve to have better technologies that can improve their lives,” she stated.
Co-investigator Dustin Tyler, who directs the Functional Neural Interface Lab at CWRU, was instrumental in developing the stimulation techniques that allow sensory signals to be transmitted from the prosthetic hand through the neural implants in the subjects’ arms.
Trial Structure and Expectations
The upcoming four-year study will involve a cohort of a dozen upper-limb amputees who will compare the traditional prosthetic arms and hands with the sensory-enabled iSens prostheses. Initially, participants will undergo a three-month testing phase during which electrodes and electronic modules will be implanted in their arms. This setup will allow them to intuitively control the prosthesis using muscle signals, with calibrated nerve stimulation designed to relay touch sensations from the prosthetic hand to the users’ brains.
Following this phase, participants will either retain their existing prostheses or receive an iSens device. They will fill out surveys regarding their usage of the prosthesis and return to the lab for monthly evaluations. After this testing period, the roles will be switched, allowing those who initially used their standard prostheses to experience the iSens technology and vice versa.
The trial’s third phase will further explore the capabilities of the iSens device by randomly assigning participants to groups. One group will use the iSens prosthesis with touch sensation enabled, while the other will utilize it with advanced motor control only. Participants will then switch groups after several weeks.
Graczyk remains optimistic about the potential impact of the iSens neuroprosthesis. “We expect our neuroprosthesis to make life better for people with amputation, but we don’t know if the biggest factor will be improved sensation or improved control, or both,” she explained.
This pioneering research could represent a significant advancement in prosthetics, potentially transforming the lives of many amputees by restoring a level of sensation and control that has been previously unattainable.