title: Knee-extension-assist for knee-ankle-foot orthoses.
abstract: Individuals with quadriceps muscle weakness often have difficulty generating the knee-extension moments required for common mobility tasks. A new device that provides a knee-extension moment was designed to help individuals perform sit-to-stand and stand-to-sit. The knee-extension-assist (KEA) was designed as a modular component to be incorporated into existing knee-ankle-foot-orthoses (KAFO). The KEA loads a set of springs as the knee flexes under bodyweight and returns the stored energy as an extension moment during knee extension. The springs can be locked in place at the end of flexion to prevent unwanted knee extension while seated. When the affected leg is unloaded, the device disengages, allowing free joint motion. A prototype KEA underwent mechanical testing and biomechanical evaluation on an able-bodied individual during sit-to-stand and stand-to-sit.
authors.affiliation: University of Waterloo, Waterloo, ON N2L 3G1, Canada. alexspring@gmail.com
authors.forename: Alexander
authors.initials: A
authors.lastname: Spring
authors.forename: Jonathan
authors.initials: J
authors.lastname: Kofman
authors.forename: Edward
authors.initials: E
authors.lastname: Lemaire
mesh_terms: D000842:Ankle / Q000502:physiology*; D001696:Biomechanical Phenomena / Q000502:physiology; D005528:Foot / Q000502:physiology*; D006801:Humans; D007717:Knee / Q000502:physiology*; D009989:Orthotic Devices; D012656:Self-Help Devices