Change of rocker function in the gait of stroke patients using an ankle foot orthosis with an oil damper: immediate changes and the short-term effects

Background: An ankle foot orthosis (AFO) using an oil damper (AFO-OD) to assist the first rocker during gait was previously developed but the effect on the other rocker functions has not been clarified. Objectives: The immediate and short-term effects on the gait of stroke patients with the AFO-OD were investigated from the viewpoint of the rocker function. Study Design: Crossover study. Methods: The gait of eight stroke patients in chronic phase without an AFO, with the AFO-OD, and the gait with AFOOD after three weeks of continuous use and gait training were measured by 3D motion analysis. Results: Immediate changes observed on use of the AFO-OD were improvements in walking speed, the spatiotemporal parameters, and the angular change of dorsiflexion of the ankle joint. Three weeks of continuous AFO-OD use and gait training showed further improvements in walking speed and the spatiotemporal parameters as well as an increase in dorsiflexion angle and plantar flexor moment of the ankle joint of the paretic limb in stance. Conclusions: These changes produced improvement of the second rocker function, but improvement of the third rocker was insufficient. Results show the importance of gait training to take full advantage of an AFO. Clinical relevance An AFO using an oil damper (AFO-OD) to assist the first rocker function during gait improves the gait of stroke patients. The immediate effects were improvements in walking speed, the spatiotemporal parameters, and the angular change of ankle joint. Three weeks of continuous use and gait training with AFO-OD shows further increase of walking speed and improvement of the second rocker function, such as increase of dorsiflexion and plantar flexor moment of the paretic limb in stance. These findings show the importance of understanding the gait of stroke patients from the viewpoint of rocker function and they also show the importance of gait training to take full advantage of an AFO.