The Effect of Vibratory Stimulation on Tissue Compliance and Muscle Activity in Elbow Flexor Spasticity

Abstract

[Purpose] This study investigated the effect of vibratory stimulation on tissue compliance and muscle activity in stroke patients with elbow flexor spasticity. [Subjects and Methods] Twenty patients who were grade 2 on the Modified Ashworth Scale (MAS) were evaluated before and after vibratory stimulation. This evaluation was done using MAS (change of clinical characteristic), a myotonometer (change in muscle tissue compliance), and surface electromyography (sEMG) (change in muscle activity). [Results] MAS results showed significant decreases immediately and three weeks after the start of vibratory stimulation. Tissue compliance significantly increased immediately (0.75, 1, and 1.25 kg) and three weeks (0.5, 0.75, 1, 1.25, and 1.5 kg) after the start of vibratory stimulation, and muscle tone decreased. Muscle activity significantly increased immediately (1 and 1.25 kg) and three weeks (0.75, 1, 1.25, and 1.5 kg) after the start of vibratory stimulation. [Conclusion] Using a myotonometer and sEMG, we demonstrated that vibratory stimulation was an effective form of therapeutic stimulation. Vibratory stimulation can be used as a non-pharmacological therapy for the neurorehabilitation of patients with spasticity.