Can virtual reality replace conventional vestibular rehabilitation tools in multisensory balance exercises for vestibular disorders? A non-inferiority study

Abstract

Background: Vestibular rehabilitation uses multisensory balance exercises to optimize the integration and weighting of sensory inputs, including visual, vestibular, and proprioceptive signals. Head-mounted displays (HMDs) have emerged as a promising tool for these exercises, offering the ability to generate unreliable or conflicting visual stimuli, thereby enhancing vestibular and proprioceptive input weighting. This study aimed to determine whether a virtual reality (VR)-based rehabilitation program using HMDs is non-inferior to a conventional program employing an optokinetic stimulator and slaved environmental surround for multisensory balance exercises.

Methods: Seventy-six participants with vestibular disorders were randomized into either the VR-based or conventional rehabilitation program for three weeks in a randomized controlled non-inferiority trial with blinded assessment. The non-inferiority margin was set at 5% of the control group's score. Both programs were multidisciplinary and included multisensory balance exercises designed to challenge sensory re-weighting. The primary outcome was the stability score, measured with eyes closed on an unstable platform using posturography, to evaluate postural control. Secondary outcomes included other variables from posturography, perceived disability assessed using the Dizziness Handicap Inventory (DHI), and tolerance to the multisensory balance exercises with unreliable or conflicting visual stimuli, assessed using the Simulator Sickness Questionnaire (SSQ).

Results: The results showed that multisensory balance exercises with unreliable or conflicting visual stimuli were well tolerated in both groups, as indicated by low SSQ scores. Both rehabilitation programs led to significant pre-post improvements in postural control and perceived disability. However, the VR program did not meet the non-inferiority criterion compared to the conventional program. The primary outcome analysis revealed a difference of - 13.36 (95% CI - 29.84 to 3.11), with the lower bound of the confidence interval (- 29.84) falling below the non-inferiority margin of -2.01. Similarly, secondary outcomes, including other variables from posturography and the DHI, also failed to meet the non-inferiority criterion.

Conclusion: Although VR rehabilitation shows innovative potential for multisensory balance training, its effectiveness was not demonstrated to be non-inferior to the conventional approach. Therefore, we recommend considering it as a complementary tool rather than a primary device for vestibular rehabilitation. Further research is needed to enhance the efficacy of VR-based rehabilitation for vestibular disorders while maintaining its tolerance. Trial registration NCT03838562.

Fig. 1

Flow Chart and Analysis Population

Fig. 2

Non-inferiority results for the primary outcomes using PP analysis (A) and mITT analysis (B). The mean scores and standard deviations for each group are shown on the left, while the differences between groups and their 95% confidence intervals are displayed on the right. To support the non-inferiority hypothesis, the lower bound of the 95% confidence interval of the differences must be above the non-inferiority margin

Fig. 3

Boxplots of the Dizziness Handicap Inventory (DHI) total score and sub-scores at pre-intervention (blue), post-intervention (green), and follow-up (light green), based on the combined mITT population from both groups. The total score is displayed in the top-left panel, the physical sub-score in the top-right panel, the functional sub-score in the bottom-left panel, and the emotional sub-score in the bottom-right panel