Characteristics of the Muscle Activities of the Elderly wearing the Lower limb Orthosis during Gait on the Treadmill

Abstract

We have developed a lower limb orthosis with a pneumatic rubber actuator, which is intended for the assistance and the enhancement of lower limb muscular activities of the elderly. For this purpose, we investigated the characteristics of the muscular activities with and without the orthosis in gait motion on treadmill. To find out the characteristics of the muscle activities, we analyzed the gait motion of the subject and flexing and extending motion of the knees and measured muscular power in the lower limb. The subjects wearing the lower limb orthosis were instructed to perform gait on the treadmill and flexing and extending motion of the knees in sitting position for monitoring of electromyogram and muscular activities. We used the C805 1F Target Board (SILICON LABORATORIES, Inc., USA) for the orthosis control. The air pressure of the pneumatic actuator was varied from one kgf/cm2 to four kgf/cm2 to find the most suitable air pressure. Through this study, we expect to find the effect of the lower limb orthosis in the gait motion and muscular activities along with the most suitable air pressure in the pneumatic actuator of the orthosis for the enhancement of muscular power for the elderly.

G1-1 Comparison of muscle adaptation toward assistive force between the young and elderly.

“…For example, Galganski et al (1993) investigated the effects of aging on motor output of the first dorsal interosseous muscle and found that the elderly could not maintain a constant sub-maximal isometric force with their index fingers. Kim et al (2009) found that lower limb orthosis reduced the activity of the biceps femoris and rectus femoris muscles in 10 elderly participants. In another study, Nasir et al (2017) investigated adaptation of assistive force while performing isometric elbow flexion in young participants.…”