Stance Control Knee Mechanism for Lower Limb Support in Hybrid NeuroprosthesisBy To, Curtis S.; Kobetic, Rudi; Bulea, Thomas C.; Audu, Musa L.; Schnellenberger, John R.; Pinault, Gilles; Triolo, Ronald J.; Journal of Rehabilitation Research and Development, Volume 48, Number 7, pages 839-850
Publication Date: 2011
Study was undertaken to develop a new hydraulic stance control knee mechanism (SCKM) to provide improved reliability and functionality over existing mechanisms for individuals with spinal cord injury (SCI) whose gait is powered by electrical stimulation of their paralyzed muscles. The SCKM was optimized for maximum locking torque for body weight support and minimum resistance when allowing for free knee motion. Ipsilateral and contralateral position and force feedback were used to control the SCKM. Through bench and nondisabled testing, the SCKM was shown to be capable of supporting torque of up to 70 Newton meters, require no more than 13 percent of the torque achievable with functional neuromuscular stimulation (FNS) to facilitate free motion, and responsively and repeatedly unlock under an applied flexion knee torque of up to 49 Newton meters. The SCKM was subsequently tested with a male participant with thoracic SCI who used an FNS system. Preliminary tests demonstrated that it could support the body and maintain knee extension during stance without the stimulation of the knee extensor muscles. This was achieved without adversely affecting gait, and knee stability was comparable to gait assisted by knee extensor stimulation during stance. Future work to further develop the SCKM is discussed.
VA Rehabilitation Research & Development Service (Web Site: http://www.rehab.research.va.gov )
Link to text: http://www.rehab.research.va.gov/jour/11/487/to487.html