Navigating the FDA Medical Device Regulatory Pathways for Pediatric Lower Limb Exoskeleton Devices

There have been significant advances in the technologies for robot-assisted lower limb rehabilitation in the past decade. However, the development of similar systems for children has been slow despite the fact that children with conditions, such as cerebral palsy, spina bifida, and spinal cord injury (SCI), can benefit greatly from these technologies. Robotic-assisted gait therapy (RAGT) has emerged as a way to increase gait training duration and intensity while decreasing the risk of injury to therapists. Robotic walking devices can be coupled with motion sensing, electromyography, scalp electroencephalography, or other noninvasive methods of acquiring information about the user's intent to design brain–computer interfaces (BCI) for neuromuscular rehabilitation and control of powered exoskeletons. For users with SCI, BCIs could provide a method of overground mobility closer to the natural process of the brain controlling the body's movement during walking than mobility by wheelchair. For adults, there are currently four Food and Drug Administration (FDA) approved lower limb exoskeletons that could be incorporated into such a BCI system, but there are no similar devices specifically designed for children, who present additional physical, neurological, and cognitive developmental challenges. The current state-of-the-art for pediatric RAGT relies on large clinical devices with high costs that limit accessibility. This can reduce the amount of therapy a child receives and slow the rehabilitation progress. In many cases, the lack of gait training can result in a reduction in the mobility, independence, and overall quality of life for children with lower limb disabilities. Thus, it is imperative to facilitate and accelerate the development of pediatric technologies for gait rehabilitation, including their regulatory path. In this article, an overview of the U.S. FDA clearance/approval process is presented. An example device has been used to navigate important questions facing device developers focused on providing lower limb rehabilitation to children in home based or other settings beyond the clinic.