Walking when utilizing a sensory feedback system and an electrical muscle stimulation gait orthosis

Electrical muscle stimulators (EMS) have been combined with a reciprocating gait orthosis (RGO) to produce an EMS-RGO system for constant velocity ambulation exercise in a spinal cord injured (SCI) individual. The objective of this study is to evaluate an auditory feedback system (AFS) used by the SCI subject when ambulating with the EMS-RGO. Three different types of auditory signals (M = metronome alone, MSL = metronome plus stride length information, and NONE = no auditory feedback) were examined at three different constant walking velocities (WV1 = 0.64 kph, WV2 = 1.22 kph, and WV3 = 1.80 kph). The experimental design was 3 x 3 full factorial with repeated measures, and the dependent variable was the absolute error (AE) of walking distance (absolute value of the distance the subject walked in one minute subtracted from the target distance). A block diagram and circuit schematic of the AFS is provided. The results indicate that at WV1 there is no significant difference of AE among the three auditory conditions (M, MSL and NONE). At WV2, the AE for the NONE auditory condition is significantly greater than the AE for M and MSL (p < 0.05). At WV3, the AE for the NONE auditory condition is significantly less than the AE for M and MSL (p < 0.05). Finally, there was no significant difference in AE between both the M and MSL auditory conditions at any of the three walking velocities. This study indicates that an adequate sensory feedback system for constant velocity control of ambulation in this SCI subject consists of metronome only auditory feedback.(ABSTRACT TRUNCATED AT 250 WORDS)