Effect and mechanism of mirror therapy on rehabilitation of lower limb motor function in patients with stroke hemiplegia

Objective: To investigate the effects of mirror therapy on rehabilitation of lower limb motor functions in patients with stroke hemiplegia and explore its neurophysiological mechanism by investigating the change rule of BOLD-fMRI imaging during treatment. Method:From September 1, 2013 to December 26, 2013, 36 stroke hemiplegia patients were randomly and evenly divided into mirror therapy group and general rehabilitation group, 18 cases in each group. All patients in both groups received routine rehabilitation treatment. The patients of the mirror therapy group were additionally given mirror therapy while the patients of the general rehabilitation group were trained to do the same movements as the mirror therapy group without visual feedback and motor imagery. Before and after treatment, the patients in each group were assessed by the Brainstorm stage of lower limb motor function, the Berg balance scale, the Functional Ambulation Category scale (FAC) and the transferring and walking parts of Functional Independent Measurement (FIM). Results: There was statistically significant difference in Brainstorm score, the Berg balance scale score, FAC score and FIM score between both groups before and after treatment. The improvement of the mirror therapy group was more obvious than that of the general rehabilitation group. In terms of the BOLD-fMRI scan, before the treatment the two groups of 8 patients showed extensive and scattered activation of bilateral cerebral cortex with the absence of activation of M1 area. After the treatment those from the mirror therapy group mainly showed the M1 activation of the opposite side while the general rehabilitation group showed no obvious change. The volume of M1 activation and LI both increased after the treatment compared with the values before the treatment. Conclusion: The application of mirror therapy, which is based on routine rehabilitation treatment, can improve lower limb motor functions for patients with stroke hemiplegia, realize more activation in the M1 area and promote the reorganization of the brain.