JMIR Publications

ABSTRACT

Background:

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Objective:

To study the feasibility, acceptability and preliminary efficacy of an immersive virtual reality (VRiKnee) assisted lower limbs exercise for knee osteoarthritis (OA).

Methods:

A convergent parallel mixed-method study was conducted in 30 participants with knee OA. After 1:1 randomization, the VRiKnee group (n=15) were assigned to perform repetitive concentric quadriceps and isometric vastus medialis oblique exercise in an immersive environment using head-mount display (HMD) for 12 weeks. The control group (n=15) completed the same exercises without VRiKnee. VRiKnee participants were interviewed at week 12 to study their acceptability and user experience. Quantitative data included feasibility outcomes such as recruitment, dropout and exercise adherence rates, and effectiveness outcomes such as the Numeral Rating Scale, Western Ontario and McMaster University Osteoarthritis Index (100 points) pain and function subscales and objective physical activity measured by metabolic equivalents (METs) using ActivPAL accelerometer. Qualitative data were analyzed by thematic analysis, followed by integration with quantitative data using joint displays.

Results:

The recruitment rate was 100%, with enrollment of 30 participants in 7.57 weeks. The median age was 63.5 (IQR 61.8-66.3) years, with 76.7% female. The dropout rate was 13.3% in VRiKnee and 6.7% in control. Median exercise adherence for VRiKnee and control groups was 77.22% and 62.08%, respectively, with adherence reduction over the study period. No statistically significant differences were observed in primary and secondary outcomes, though positive trends were observed in pain and function. Cybersickness was reported by 5 participants (33.3%) in the VRiKnee group. In the qualitative analysis, 4 themes, 11 subthemes and 16 quotes were generated, identifying facilitators and barriers with practical suggestions to enhance the usability of VRiKnee.

Conclusions:

VRiKnee demonstrated feasibility, acceptability and potential efficacy in managing knee OA. Future trials of larger sample sizes and better VR designs will confirm its role in clinical practice. Clinical Trial: Chinese Clinical Trial Registry (CHiCTR2100046313)