Development of a robotic ankle assist device to improve mobility in individuals with movement disorders.

PROJECT SUMMARY/ABSTRACT A child’s ability to engage in physical activity is essential to their health, independence, and general well-being. Many of the 500k children in the United States with cerebral palsy (CP), the most common cause of pediatric physical disability, have difficulty walking and participating in physical activity. This reduced physical activity in CP is a primary contributor to the greater incidence of metabolic dysfunction, cardiovascular disease, osteoporosis, pain, and diminished psycho-social quality of life. Unfortunately, half of all ambulatory children with CP lose the ability to walk independently in adulthood, indicating that the current approaches for treating these individuals do not result in meaningfully improved mobility over time. Physical Therapy (PT) is essential for treating CP but the amount of PT is generally insufficient, and the delivery of PT can be inefficient. There is currently no viable way to provide a sufficient dose of PT that will lead to long-term improvements in mobility and reduce the negative physical and social outcomes noted above. BiOMOTUM’s (applicant) goal is to create a reimbursable wearable system for children with CP that will (1) make walking easier and improve free-living mobility, (2) increase the dose and precision of ankle plantar-flexor therapy to produce lasting improvements in neuromuscular function, and (3) create a virtual community to incentivize the use of the system and track improvement. To achieve these goals, this project uses a lightweight, low-profile, battery-powered, wearable Robotic Ankle Assistive Device (RAAD). The overall objectives of this proposal are to establish feasibility of the RAAD system to improve mobility in free-living settings and to establish the RAAD as an effective tool to provide increased dose and precision of targeted ankle therapy. The first specific aim is to complete a personal-use feasibility analysis of ankle mobility assistance. It is hypothesized the children will be able to safely walk faster and travel farther in the community when using the RAAD device vs. without the device. The second specific aim is to gather feedback to design and prototype a minimum viable product for use in clinical and community settings. The third specific aim is to quantify the potential for the RAAD system to increase the effectiveness of clinical gait therapy. Individuals with CP will complete three training sessions: RAAD assistance, RAAD resistance and standard of care. Muscle activity and step activity will be measured during each session. It is hypothesized that the RAAD assistance and resistance therapy will improve ankle plantar-flexor muscle activity and treatment session quality compared to traditional physical therapist-guided gait training. The fourth specific aim is to assess the benefits of repeated gait training with RAAD assistance and resistance. Individuals with CP will participate in a 4-week assistance or resistance intervention and mobility outcomes will be quantified pre and post intervention. It is hypothesized that both assistance and resistance training will improve mobility outcomes. This proposal paves the way for commercializing the device and implementing future longitudinal interventions that will investigate the potential for RAAD to improve quality of life and long-term clinical outcomes.