The effect of adding virtual reality-based rehabilitation to conventional physiotherapy on pain, functional ability and static balance control in patients with total knee arthroplasty

Background Physiotherapy in patients with total knee arthroplasty (TKA) is necessary to reduce pain, return to daily activities, and maintain balance. Today, virtual reality (VR) is being used to provide real-time visual feedbacks during the exercise. Hence, aim of the present study was to evaluate the effect of adding virtual reality-based therapy in comparison to conventional physiotherapy on the pain, functional ability, and static balance in the acute phase after TKA. Methods Fifty-two patients who underwent TKA (11male, 41 female, mean age 61.92 ± 6.91 years) were randomly assigned into two groups: a control group (n = 24) and an intervention group (n = 28). The control group received conventional physiotherapy, whereas the intervention group participated in a combination of VR-based therapy and conventional physiotherapy. The primary outcome was functional ability, assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Secondary outcomes included pain, measured using the Numeric Rating Scale (NRS), and static balance, assessed with the Wii Balance Board. Static balance control was evaluated using center of pressure (COP) parameters, including COP area and mean velocity, under two conditions: open eyes and closed eyes. Pain and functional ability were evaluated at baseline, post-treatment, and at the one-month follow-up. Static balance measurements were taken at baseline and post-treatment. Results The intervention group demonstrated significant improvements compared to the control group. The WOMAC scores and pain levels showed greater reductions at both the post-treatment and follow-up phases (effect size [ES] = 36%, P < 0.001). The static balance parameters improved in both groups; however, the intervention group exhibited significantly greater reductions in COP ellipse area in the standing position (P < 0.001) and mean velocity in the mediolateral direction (P < 0.001, ES = 23%). Additionally, anteroposterior mean velocity with open eyes decreased significantly only in the intervention group (P < 0.001). No significant changes were observed in static balance parameters under the eyes-closed condition. Conclusions This study demonstrated that VR-based exercise therapy significantly improved knee function, static balance, and pain management in TKA patients during early rehabilitation. The intervention group exhibited superior improvements compared to the control group, highlighting the effectiveness of integrating VR-based therapy with conventional physiotherapy. These findings suggest that this combined approach can optimize recovery and improve rehabilitation outcomes in the early phase following TKA. Trial registration: The study was retrospectively registered in the Iranian Clinical Trials Registry with the number IRCT20230524058283N1.