Ankle-foot Orthosis With an Oil Damper Versus Nonarticulated Ankle-foot Orthosis in the Gait of Patients With Subacute Stroke: A Randomized Controlled Trial

Abstract

BackgroundGait improvement in patients with stroke using ankle-foot orthosis (AFO) has been compared to the effects of non-AFO use in previous studies, but the effect of different kinds of AFOs has not been clear. When considering the effect of different kinds of AFOs on gait, the dorsiflexion and plantar flexion moment of resistance is considered a key determinant of functional effect. In this study, the effect on gait of using an AFO with an oil damper (AFO-OD), which has plantar flexion resistance but no dorsiflexion resistance, and a nonarticulated AFO, which has both dorsiflexion and plantar flexion resistance, were compared in a randomized controlled trial. MethodsForty-one patients (31 men, 10 women; mean age 58.4 ± 11.3 years) in the subacute phase of stroke were randomly allocated to two groups to undergo 2 weeks of gait training by physiotherapists while wearing an AFO-OD or a nonarticulated AFO. A motion capture system was utilized to measure shod gait without orthosis at baseline and after training with the allocated AFO. Data analysis was performed focused on the spatial and temporal parameters, ground reaction force, shank-to-vertical angle, and ankle joint kinematics and kinetics. Two-way mixed ANOVA was performed to clarify the effect of AFO use and the difference between the two AFOs. ResultsThirty-six patients completed the study (17 in the AFO-OD group and 19 in the nonarticulated AFO group). Spatial and temporal parameters and ankle joint kinematics were improved after 2 weeks in both AFO groups. Interactions were found for the range of shank-to-vertical angles in paretic single stance and ankle peak power absorption. In the AFO-OD group, both parameters improved when the participants walked with the AFO compared to the shod gait, but there was no change in the nonarticulated AFO group. Power generation was not increased in either AFO group. ConclusionsThe results of this study showed that AFO with plantar flexion resistance but without dorsiflexion resistance improved the range of the shank-to-vertical angle and ankle power absorption but not power generation in a paretic stance. (336/350 words)Trial registration: UMIN000028126 Registered 1 August 2017,https://upload.umin.ac.jp/cgi-bin/icdr/ctr_menu_form_reg.cgi?recptno=R000032197