Alterations in EMG patterns during robotic assisted walking

Robotic devices are being developed for gait rehabilitation with promising results. This study focuses on the effectiveness of one such device: the Lokomat, a robotic gait orthosis. Muscle activations patterns (EMG) generated in normal subjects while walking on a treadmill were compared to those exhibited during Lokomat walking. Eight of the major leg muscles were chosen for measurement. For each trial, the average EMG activity was computed at various phases of the gait cycle, and compared across a variety of walking speeds. We hypothesized that the differences found between treadmill and Lokomat walking would create a greater understanding for the appropriateness of using this device in clinical rehabilitation. The results show significant differences in muscle firing patterns in certain parts of the gait cycle between treadmill and Lokomat walking. Because the robotic orthosis limits the degrees of freedom of the leg and pelvis, it will lead to changes in a natural gait pattern. Although the robotic orthosis does not exactly mimic the gait patterns of natural ambulation, it offers numerous benefits in gait rehabilitation.