Immediate therapeutic effect of interferential current therapy on spasticity, balance, and gait function in chronic stroke patients: a randomized control trial

Objective: To determine whether a single trial of interferential current therapy (ICT) can immediately alleviate spasticity and improve balance and gait performance in patients with chronic stroke. Design: Randomized, placebo-controlled clinical trial. Setting: Inpatient rehabilitation in a local center. Subjects: A total of 42 adult patients with chronic stroke with plantar flexor spasticity of the lower limb. Intervention: The ICT group received a single 60-minute ICT stimulation of the gastrocnemius in conjunction with air-pump massage. In the placebo-ICT group, electrodes were placed and air-pump massage performed without electrical stimulation. Main measures: After a single ICT application, spasticity was measured immediately using the Modified Ashworth Scale (MAS), and balance and functional gait performance were assessed using the following clinical tools: Functional Reach Test (FRT), Berg Balance Scale (BBS), Timed Up and Go Test (TUG), and 10-m Walk Test (10MWT). Results: Gastrocnemius spasticity significantly decreased in the ICT group than in the placebo-ICT group (MAS: ICT vs placebo-ICT: 1.55 +/- 0.76 vs 0.40 +/- 0.50). The ICT group showed significantly greater improvement in balance and gait abilities than the placebo-ICT group (FRT: 2.62 +/- 1.21 vs 0.61 +/- 1.34, BBS: 1.75 +/- 1.52 vs 0.40 +/- 0.88, TUG: 6.07 +/- 6.11 vs 1.68 +/- 2.39, 10MWT: 7.02 +/- 7.02 vs 1.96 +/- 3.13). Spasticity correlated significantly with balance and gait abilities (P < 0.05). Conclusion: A single trial of ICT is a useful intervention for immediately improving spasticity, balance, and gait abilities in chronic stroke patients, but not for long-term effects. Further study on the effects of repeated ICT is needed.