Preliminary investigation into the effects of visual feedback distortion on range of motion

In this study, a robotic orthotic device with one degree of freedom was used for assessment of individuals with chronic stroke and resultant hemiparesis. The specific aim was to investigate the effect of visual feedback distortion on range of motion (ROM) at the elbow and wrist joints as measured by the Arm IntelliStretch platform from Rehabtek LLC. It was hypothesized that introducing visual feedback distortion in increments under the just noticeable difference of two degrees would directly correspond to an increase in ROM at both the wrist and elbow joints when compared to ROM measured by the IntelliStretch system without visual feedback distortion. Ten individuals an average of 11 years post stroke (SD: 9.7) participated in this study. At the elbow joint, repeated measures ANOVA showed a significant effect of distortion (F(4, 36) = 2.69, p < 0.047). Similar trends were seen at the wrist joint, though these results were not statistically significant.