Novel lower limb robot-assisted gait phase stimulation enhances walking and balance in stroke patients: a pilot trial

BACKGROUND: Hemiplegic patients often experience weakness in key muscle groups during gait, significantly impairing walking and balance. To address this, we developed a novel gait phase-specific functional electrical stimulation (FES) delivered through a lower limb rehabilitation robot. This pilot study investigated the effects of combining gait phase-specific FES with robot-assisted gait training (RAGT) in subacute stroke patients. METHODS: Fifty-one hemiplegic stroke patients were randomized into experimental, control, and placebo groups (17 each). The experimental group received conventional training plus gait phase-specific FES with RAGT. The control group underwent conventional training, traditional FES, and RAGT. The placebo group received conventional training with sham FES and RAGT. Interventions were administered daily, five times weekly, for three weeks. Assessments were conducted at baseline, weekly during treatment, and five weeks post-treatment completion. The primary outcomes were the 10-Meter Walk Test (10MWT) and the Berg Balance Scale (BBS). Secondary outcomes included the Fugl-Meyer Assessment (FMA-LE), the Manual Muscle Test (MMT), and the Modified Ashworth Scale (MAS). RESULTS: Forty-eight patients completed the trial. Two-way repeated-measures ANOVA revealed significant time, group, and time × group interaction effects for primary outcomes (10MWT and BBS, P < 0.01). The experimental group showed significantly greater improvements in 10MWT versus control and placebo groups at week 2, 3, and 5th-week follow-up (P < 0.05). Similarly, BBS scores were highest in the experimental group at week 3 and follow-up (P < 0.01), with control also outperforming placebo (P < 0.05). Secondary outcomes (FMA-LE, MMT, MAS) improved across all groups (P < 0.0001), but the experimental group exhibited superior gains at the follow-up (P < 0.01). No significant differences were observed between control and placebo groups (P > 0.05). CONCLUSIONS: Combining gait phase-specific FES with RAGT can effectively improve walking and balance function in stroke patients.