Virtual reality obstacle avoidance training can be enhanced by physical feedback via perturbations: A proof-of-concept study.

Background: Fall injuries resulting from trips are a major health concern. Virtual reality (VR) offers an effective way of training obstacle avoidance while walking due to its ability to provide safe and meaningful real-time feedback during rehabilitation. This proof-of-concept study examined the benefit of providing physical feedback during obstacle avoidance gait training using VR.

Methods: Twenty-six young adults walked on an instrumented treadmill while wearing a head-mounted display in two 8-min conditions. Virtual obstacles to be avoided were presented in a VR-only condition and a VR + Perturbation (VR + P) condition where additional rapid belt acceleration simulated tripping on an obstacle.

Results: A lower obstacle collision rate, greater step length and height of the leading foot over the obstacles were found in the VR + P condition compared to the VR-only condition (p < 0.05). Step height of the trailing foot over the obstacles significantly decreased over time during the VR-only condition (p < 0.01) but not during the VR + P condition. The margin of stability significantly improved over time during the VR + P condition only (p < 0.01).

Conclusions: Immediate physical feedback via treadmill belt acceleration can improve obstacle avoidance performance in a virtual environment. Future research is required to examine the generalizability of this finding to other populations and real-world falls.