Effect of a soft exosuit on gait kinematics

Anti-gravity exosuits supporting hip and knee extension have emerged for overground training. This study investigated their effect on kinematics in individuals with incomplete spinal cord injury (iSCI) compared to regular walking and to walking with an overground BWS system. Fourteen individuals with iSCI were tested during overground walking in three conditions: regular, exosuit, and BWS. Kinematics were assessed using the Xsens MVN motion capture system. Maximum hip extension was larger for exosuit compared to regular walking (Δ4.7°, 95% CI [1.4, 7.9]), but was not different compared to BWS. Mean knee flexion was smaller for exosuit compared to regular walking (Δ−1.7°, 95% CI [−3.0, −0.4]) and compared to BWS (Δ−3.5°, 95% CI [−5.4, −1.6]). Most secondary outcome measures (e.g. walking speed, stride length, step width, ML COM excursion) showed no differences between exosuit and regular walking. Comparing exosuit to BWS, most secondary outcome measures (e.g., walking speed, stride length, stride time, trunk inclination) favored BWS. An anti-gravity exosuit resulted in increased hip and knee extension, but did not translate into other gait improvements. Given the more favorable outcomes of the BWS system compared to the exosuit, exosuit design improvements are needed to be effectively implemented in gait rehabilitation after iSCI.