Development of Knee Ankle Foot Orthosis for Gait Rehabilitation Training using Plantaflexion and Knee Extension Torque

족저굴곡과 무릎 신전 토크를 이용한 보행 재활 훈련용 장하지 보조기 개발

  • 김경 (전북대학교 의용생체공학과) ;
  • 김재준 (전북대학교 헬스케어공학과) ;
  • 허민 (전북대학교 헬스케어공학과) ;
  • 정구영 (전북대학교 헬스케어기술개발사업단) ;
  • 고명환 (전북대학교 의학전문대학원 재활의학교실, 의과학 연구소 및 임상의학연구소) ;
  • 권대규 (전북대학교 바이오메디컬공학부, 고령친화복지기기연구센터)
  • Received : 2010.06.10
  • Accepted : 2010.07.20
  • Published : 2010.10.01


The purpose of this study was to test the effectiveness of a prototype KAFO (Knee-Ankle-Foot Orthosis) powered by two artificial pneumatic muscles during walking. We had previously built powered AFO (Ankle-Foot Orthosis) and KO (Knee Orthosis) and used it effectively in studies on assistance of plantaflexion and knee extension motion. Extending the previous study to a KAFO presented additional challenges related to the assistance of gait motion for rehabilitation training. Five healthy males were performed gait motion on treadmill wearing KAFO equipped with artificial pneumatic muscles to power ankle plantaflexion and knee extension. Subjects walked on treadmill at 1.5 km/h under four conditions without extensive practice: 1) without wearing KAFO, 2) wearing KAFO with artificial muscles turned off, 3) wearing KAFO powered only in plantaflexion under feedforward control, and 4) wearing KAFO powered both in plantaflexion and knee extension under feedforward control. We collected surface electromyography, foot pressure and kinematics of ankle and knee joint. The experimental result showed that a muscular strength of wearing KAFO powered plnatarfexion and knee extension under feedforward control was measured to be lower due to pneumatic assistance and foot pressure of wearing KAFO powered plnatarfexion and knee extension under feedforward control was measured to be greater due to power assistance. In the result of motion analysis, the ankle angle of powered KAFO in terminal stance phase was found a peak value toward plantaflexion and there were difference of maximum knee flexion range among condition 2, 3 and 4 in mid-swing phase. The current orthosis design provided plantaflexion torque of ankle jonit in terminal stance phase and knee extension torque of knee joint in mid-swing phase.


Supported by : 한국학술진흥재단


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