Increase of muscle activities in hemiplegic lower extremity during driving a cycling wheelchair.

For the patients with severe hemiplegia, long-time wheelchair sitting is unavoidable, which however increases a risk of secondary impairments due to non-use of the affected leg. A cycling wheelchair (C-W/C) has a possibility to activate paretic muscle through self-locomotion with bilateral pedaling. We therefore measured driving speed of C-W/C and electromyogram (EMG) in both legs during driving in the healthy adults and severe hemiplegic patients. Ten healthy volunteers (mean age 32.8, 26-45 years) and ten non-ambulatory post-stroke patients (mean age 69.0, 55-81 years) with complete or semi-complete hemiplegia participated in this study. EMG was recorded from the key muscles for cycling during isometric movement as baseline and during driving a C-W/C straightforward. All of the patients could drive a C-W/C with mean maximum driving speed of 46.6 (31.7-61.7) m/min, which was about half of that in the healthy subjects and within practical level. Root mean square of EMG (R-EMG) as a parameter reflecting muscle activity was compared between baseline and C-W/C driving. There was no increase in most of the values of R-EMG during driving in the healthy subjects and in the intact side of the hemiplegic patients. In contrast, significant increase was found during driving in several paretic muscles, despite that EMG of the paretic leg showed almost silent at baseline. These results suggest C-W/C can induce muscle activities of the paretic leg and provide a chance of practical locomotion even for the severe hemiplegics. Daily use of a C-W/C may contribute to restore paretic leg function.