title: A stochastic model of knee angle in response to electrical stimulation of the quadriceps and hamstrings muscles.
abstract: A novel stochastic model of knee angle in response to stimulation of the quadriceps and hamstrings muscle groups is presented. This model includes uncertainty due to fatigue and day-to-day changes in the stimulated muscles. The model consists of a normally distributed random variable whose mean and standard deviation vary with time and is characterized using data from a complete spinal cord injuries subject. The experimental data show a significant difference between the left and right legs under certain conditions, and suggest that fatigue-related and day-to-day variation may also be important. The purpose of this model is to generate more realistic electrically stimulated knee movements. This stochastic modeling technique could be incorporated into a comprehensive model of a joint actuated with electrical stimulation, and has great potential as a tool for analyzing closed-loop performance of electrically stimulated systems.
authors.affiliation: Institute of Biomaterials and Biomedical Engineering, University of Toronto, Canada. clynch@ieee.org
authors.forename: Cheryl L
authors.initials: CL
authors.lastname: Lynch
authors.forename: Milos R
authors.initials: MR
authors.lastname: Popovic
mesh_terms: D004599:Electric Stimulation Therapy; D006801:Humans; D007719:Knee Joint / Q000502:physiology* / Q000503:physiopathology; D008954:Models, Biological; D015233:Models, Statistical; D018763:Muscle Fatigue; D018482:Muscle, Skeletal / Q000502:physiology / Q000503:physiopathology; D052097:Quadriceps Muscle / Q000502:physiology* / Q000503:physiopathology; D013119:Spinal Cord Injuries / Q000503:physiopathology / Q000628:therapy*; D013269:Stochastic Processes