Examination of Factors Related to the Effect of Improving Gait Speed With Functional Electrical Stimulation Intervention for Stroke Patients

Background: Functional electrical stimulation (FES) for patients with stroke and foot drop is an alternative to ankle foot orthoses. Characteristics of FES responders and nonresponders have not been clarified. Objectives: (1) To investigate the effects of treatment with FES on patients with stroke and foot drop and (2) to determine which factors may relate to responders and nonresponders. Design: Multicenter, nonrandomized, prospective study. Setting: Multicenter clinical trial. Participants: Participants included those who experienced foot drop resulting from stroke, were older than 20 years, and could provide consent to participate; they were enrolled from hospitals between January 2013 and September 2015 and performed rehabilitation with FES. Methods: Stroke Impairment Assessment Set Foot-Pat Test (SIAS-FP), Fugl-Meyer Assessment for Lower Extremity (FMA- LE), Modified Ashworth scale (MAS) for ankle joint dorsiflexion and plantar flexion muscles, range of motion (ROM) for ankle joint, 10-m walking test (10mWT), Timed Up & Go test (TUG), and 6-minute walking test (6MWT) were evaluated pre- and postintervention. Age, gender, type of stroke, onset times of stroke, paretic side, Brunnstrom stage of the lower extremity (Br. stage-LE), Functional Independence Measure (FIM), Functional Ambulation Category (FAC), poststroke months, number of interventions, total hours of interventions, and whether a brace was used were extracted from patients' medical records and collected on the physiological examination day. Main Outcome Measurements: The authors examined 10mWT and age, gender, type of stroke, onset times of stroke, paretic side, Br. stage-LE, FIM, FAC, poststroke months, number of interventions, total hours of interventions, whether a brace was used, SIAS-FP, FMA-LE, MAS, ROM, TUG, and 6MWT before intervention. Participants were divided into nonresponders and responders with a change in 10mWT of <0.1 and >= 0.1 m/s, respectively. Single and multiple regression analyses were used for data analysis. Additionally, the changes between groups were compared. Results: Fifty-eight responders and 43 nonresponders were enrolled. The between-group differences, compared for changes between pre- and postintervention, were significant in terms of changes in SIAS-FP (P = .02), 10mWT (P < .001), 10-m gait steps (P < .001), TUG (P = .04), and 6MWT (P = .006). In the adjusted regression model, gender (odds ratio [OR], 3.92; 95% confidence interval [CI], 1.426-12.25; P = .007), number of interventions (OR, 1.028; 95% CI, 1.003-1.070; P = .03), and active ankle joint dorsiflexion ROM (OR, 1.047; 95% CI, 1.014-1.088; P = .005) remained significant. Conclusion: The factors related to 10mWT showing changes beyond the minimal clinically important difference were found to be patient gender, number of interventions, and active ankle joint dorsiflexion ROM before intervention. When patients with stroke who have greater active ankle joint ROM, and are female, use FES positively, they may benefit more from using FES.