## 4 Discussion  
The main results of this study, which evaluated the effects of a complementary intervention combining AVGs and CPT on perceived functional disability in older adults with knee or hip OA, were the following. (i) The EG showed progressive improvement at all time points, achieving moderate to large improvements in all WOMAC scores by the end of the intervention, while the CG only showed significant changes at the end, with moderate improvements in WOMAC-function and total scores. (ii) The EG showed greater improvements in WOMAC-pain and the GRoC scale compared to the CG. (iii) At follow-up, the EG maintained most of the improvements, whereas the CG tended to regress. (iv) The EG had a higher proportion of Rs, particularly in WOMAC-pain, with a low proportion of ARs,  
Figure 4: Flow of participants according to change in their functional disability stratification (total WOMAC score) between quartiles. CG, control group; EG, experimental group. Figure 3: MCID thresholds for WOMAC scores (upper and lower dashed lines) and change (\(\Delta\)) in each participant’s scores (vertical bars) for classification as responders, non-responders, and adverse responders. Subfigures A, B, and C represent the pain, stiffness, and function subscales of the WOMAC, respectively, while Subfigure D illustrates the total WOMAC score. CG, control group; EG, experimental group. while the CG had a predominance of NRs, with a higher proportion of ARs compared to the EG. (v) In the EG, 70% of participants improved their quartile position, 23.3% remained in their initial quartile, and only 6.6% worsened. In contrast, 50% of the CG improved their quartile, 40% remained, and 10% worsened. These results suggest that complementing CPT with AVGs optimizes gains in self-perceived functionality, enhancing the rehabilitation process. Additionally, no adverse events related to AVGs were reported, demonstrating the safety of the intervention. Improving WOMAC scores is relevant because it increases the perceived ability to perform daily activities with less pain and joint stiffness [36], which can positively influence quality of life by enhancing functional status [48]. Additionally, greater mobility is key to preventing falls, preserving cognitive function, reducing the impact of sedentary behavior, and promoting emotional well-being. These factors also help reduce costs and alleviate the burden on healthcare systems [49]. Previous studies suggest that using AVGs as a complementary therapy in patients with OA leads to significant improvements in perceived functional disability, which is consistent with the present research. In the studies by [PERSON] et al. (2016) and [PERSON] and [PERSON] (2022), the use of systems like the Xbox 360 and MarVAJED, respectively, combined with conventional exercise, was more effective than conventional exercise alone in improving WOMAC scores [20,21]. Similarly, [PERSON] et al. (2023) found that immersive VR combined with CPT generated additional benefits [50]. These findings, which are in line with those of the present study, highlight the synergistic enhancing effect of different AVG modalities on functional perception. On the other hand, trials where AVGs were used as a standalone intervention have also shown favorable results compared to CPT for WOMAC [22,23,51]. However, [PERSON] et al. (2020) reported no significant differences between groups [51]. The latter approach differs from the current study; however, it is also noteworthy, given the robust scientific evidence supporting the positive effects of physical exercise as a first-line treatment for OA [8]. Our protocol included the complementary use of AVGs, which aligns with previous recommendations [25,52]. In this regard, although the review by [PERSON] et al. (2021) reports positive outcomes from AVGs alone, it concludes that their combination with physical training is particularly promising for improving postural balance and reducing the risk of falls in older adults [52].