Download Full Text (1.5 MB)
Knee-ankle-foot orthoses (KAFOs) are commonly prescribed for individuals with knee instability or quadriceps weakness resulting from a variety of conditions such as spinal cord injury, stroke, spina bifida, and cerebral palsy. A locking KAFO fixes the leg fully straight and is the most prescribed orthotic intervention for these conditions. However, the functional benefits of lower extremity orthoses are maximally realized in stance-controlled knee-ankle-foot orthoses (SC-KAFOs) which allow free knee motion during swing but lock during stance. Existing SC-KAFO options are generally unreliable or expensive, and thus an unmet need exists for a reliable, versatile orthosis which can be manufactured at relatively low cost. The SC-KO team is working to meet this need by developing an intelligent stance-controlled knee orthotic with an any-angle locking mechanism controlled by a microprocessor based on information received from onboard inertial gait-phase sensing. The resulting device will allow for reliable knee locking for support during the stance phase, easy unlocking even under load for the free swing phase, and predictable, safe behavior on stairs and uneven terrain. The system is being developed as a knee-only orthosis but can be adapted for a full knee-ankle-foot orthosis, with ankle support being prescribed as needed. The first system developed will be configured for pediatric use to address mobility impairments arising from cerebral palsy and spina bifida with CURE Ethiopia serving as the clinical partner for the development and testing.
Funding for this work provided by The Collaboratory for Strategic Partnerships and Applied Research.
Messiah University, Messiah College, Engineer, community, service
Witt, Jordan M.; Fertig, Levi M.; Barton, Jacob M.; Cornwell, Ethan R.; and Farris, Ryan J., "A Low-Cost Microprocessor-Controlled Stance-Control Knee Orthosis for Pediatric Mobility Impairments" (2022). 2022 Collaboratory/Engineering Symposium. 6.