The changes of improvement-related motor kinetics after virtual reality based rehabilitation

Stroke is a major cause of adult disability and up to two thirds of stroke survivors have left with motor deficits of the affected upper limb (UL). Rehabilitation is the main therapeutic approach for reducing poststroke functional deficits but significant variability exists between patients regarding rehabilitation efficacy. Because the recovery mechanisms induced by rehabilitation are not fully understood, it is still not clear which treatment approaches and techniques are most beneficial. Virtual reality (VR) is a computer-based environment that provides the users an immersive experience of a synthetic world and allows a systemic testing of human functions under the simulated environment of controllable parameters. A large body of evidence has demonstrated the efficacy of VR based rehabilitation for improving the upper limb functional recovery. However, the question which components in the VR game are most valuable for promoting the recovery has not been examined. This study aims to identify the motion kinetics extracted from the VR based rehabilitation that are significantly correlated with the functional improvement. Twenty-one stroke patients were recruited and received 1 hour rehabilitation with the intensity of 3 times per week over 8 weeks, in total 24 training sessions, using a home-made VR program. All patients underwent the evaluation of their function before and after rehabilitation by Fugl-Meyer assessment (FMA). The parameters of human kinetics, such as speed/max speed, velocity and trajectory during VR-based rehabilitation were recorded digitally and the changes of the kinetics after finishing 24 training sessions were then correlated with the post-rehabilitation changes of FMA. The statistic result showed that the increase of efficiency, speed stability and straightness of trajectory leads to a better functional improvement, in addition to the increase of palm strength. In conclusion, the changes of the improvement-related motor kinetics could serve as guidance when designing the individualized treatment strategy.