Immediate synergistic effect of a trunk orthosis with joints providing resistive force and an ankle–foot orthosis on hemiplegic gait

Purpose The synergistic effects of a trunk orthosis and an ankle-foot orthosis (AFO) in stroke patients with a hemiplegic gait are unclear. We previously developed a trunk orthosis with joints providing resistive force (TORF) to modify malalignment of the trunk and pelvis and confirmed its positive effects in stroke patients during level walking without an AFO. The aim of the present study was to determine if this trunk orthosis and an AFO have synergistic effects during level walking in community-dwelling patients with chronic stroke. Methods Twenty-eight community-dwelling stroke patients performed level walking at a self-selected speed with an AFO and again while wearing a TORF (TORF group) or a corset (control group). Spatiotemporal, kinematic, and kinetic data were recorded using a three-dimensional motion analysis system. Results When compared with the control group, the TORF group showed significant increases in walking speed, number of steps on the paretic leg per minute, and peak ankle plantar flexion moment during the single stance phase. Conclusion The TORF increased the ankle joint plantar flexion moment at the end of the single stance phase during level walking in stroke patients, leading to an increase in their gait speed because of the modified trunk and pelvis alignment.