Browsing by Subject "AFO"

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    Design of A Variable-Stiffness Ankle-Foot Orthosis Emulator
    (2020-08) Anderson, Rachel
    Ankle-foot orthoses (AFOs) are passive devices used to improve gait in children with cerebral palsy. They are characterized by a torsional stiffness and ankle neutral angle. For this project, a lightweight ankle exoskeleton was designed to emulate the spring-like behavior of a traditional AFO for a wide range in torsional stiffnesses and neutral angles. This was achieved by utilizing the principles of a cantilever beam to generate a desired stiffness profile and lightweight hydraulics to transmit forces from a power source worn at the waist to the device at the ankle. The proposed device was evaluated using FEA and CAD modeling and met most design requirements. The next stage of design evaluation will involve a physical prototype before the final product is implemented in a clinical trial at Gillette Children’s Specialty Healthcare.
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    Evaluating and Improving the Efficacy of Ankle Foot Orthoses for Children with Cerebral Palsy
    (2017-01) Ries, Andrew
    Ankle foot orthoses (AFOs) are commonly recommended for individuals with cerebral palsy (CP) as a means to improve gait. Goals of this dissertation were to evaluate the current efficacy of AFO use for children with CP, investigate the biomechanical mechanism of how AFOs influence gait, and describe new methods for analyzing and improving AFO outcomes as they pertain to gait. Retrospective data analysis, statistical machine learning, and simulation techniques were used to achieve these goals. Data analysis revealed that the general efficacy of AFO use was poor. However, a data driven model developed through machine learning techniques suggests that efficacy can likely be improved by using the model to recommend AFO prescriptions for individuals that are predicted to improve their gait with AFO use and refrain from prescribing AFOs for individuals whose gait will not improve with AFO use. Investigations of gait efficiency and muscle function revealed new factors that could potentially be leveraged to improve the efficacy of AFO use. Finally, an AFO design redundancy between two commonly prescribed AFOs was identified, eliminating misconceptions about the efficacy of a redundant AFO design. The techniques and conclusions presented in this dissertation have the potential to significantly improve the efficacy of AFO use for children with CP.