Figure 1.

University of Michigan Knee-Ankle-Foot Orthosis (KAFO). Two pictures of the unilateral (left leg) knee-ankle-foot orthosis (KAFO) with artificial pneumatic muscles display the thigh and shank sections made from carbon-fiber and the foot section made from polypropylene. The orthoses were custom molded from a cast unique to each subject. Hinge joints at the ankle and knee allowed free motion in the sagittal plane. We used steel brackets to attach two artificial pneumatic muscles (a plantar flexor and a dorsiflexor) around the ankle and four around the knee (two extensors and two flexors). Each artificial pneumatic muscle had a compression load transducer mounted in series on the proximal steel bracket attachment and a release valve for quick connection to the pressurized air source. A special shoe was worn over the foot section during walking trials.