The dynamic response carbon fiber Intrepid Dynamic Exoskeletal Orthosis (IDEO) restricts ankle movement, so it must compensate to simulate plantarflexion and allow smooth forward progression during gait. To determine the influence of wedge height and durometer on the walking gait of those using the IDEO, researchers evaluated 12 individuals as they walked repeatedly over level ground with their devices and six different heel wedges of soft or firm durometer with 1, 2, or 3cm height. The results showed that changes in wedge height and durometer systematically affected foot loading. According to the study, published online September 4 in Prosthetics and Orthotics International, participants preferred wedges that produced ankle moment zero crossing timing, peak internal knee extension moment timing, and roll-over shape center of curvature anterior-posterior position close to that of able-bodied individuals,
The trials determined that height and durometer significantly affected the time to peak center of pressure velocity, the time to peak internal dorsiflexion and knee extension moments, the time to ankle moment zero crossing, and roll-over shape center of curvature anterior-posterior position. Wedge height also had a significant influence on peak center of pressure velocity, peak dorsiflexion moment, time to peak knee extension moment, and roll-over shape radius and vertical center of curvature. Changing wedge height and durometer also significantly alters loading of the foot and has great potential to improve an individual’s gait, according the authors.