Objective: To determine the effect of virtual reality (VR) games on improving balance in different groups of neurological patients with a particular focus on the study quality and to determine the gold standard in VR training in these groups. Materials and Methods: A systematic review of controlled trials published between January 2009 and December 2017 was conducted. The PubMed, SCOPUS, SPORTDiscus, and Medline databases were searched. Studies involved patients with stroke or Parkinson's disease or children with cerebral palsy. The Physiotherapy Evidence Database (PEDro) scale was used to assess the methodological quality of the included studies. Results: A total of 20 studies met the inclusion criteria. The PEDro scores ranged from 4 to 8 points. Analysis of the rehabilitation programs revealed a very large discrepancy in the planned volume of exercises in different subgroups of patients. Conclusions: Overall, the comparison of VR interventions between conventional rehabilitation and no intervention exhibited significantly better results. However, these results should be interpreted with great caution due to the large diversity of the systems, games, and training volume used in the VR therapy. In all included studies, only several articles included objective methods to assess the effect of VR. In addition, most of the articles showed a high risk of bias, such as a lack of randomization and blinding or a small sample size. That is why further well-designed randomized control trials are required to evaluate the influence of VR on balance in different groups of neurological patients.

Background: Gait deviations may negatively affect the articular surfaces of the lower extremity joints and lead to some minor degenerative changes. The simplest method for gait evaluation is to assess the symmetry of its parameters, assuming that each undisturbed gait should be symmetrical. This study aims to quantify the degree of asymmetry of kinematic and kinetic parameters caused by the presence of different ankle orthosis settings using Dynamic Time Warping (DTW). Methods: Barefoot gait and gait with four different walker settings were investigated in eighteen healthy persons. Kinematic and kinetic parameters were measured using the Vicon system and Kistler plates. Symmetry was assessed using the DTW method. Results: It was shown that the presence of different ankle orthosis settings significantly disturbs the symmetry of all lower limb kinematic parameters and only knee and hip torques. The highest values of asymmetry were noted for the walker set at 15° of dorsiflexion (15DF). Conclusions: The DTW method allowed us to quantify the degree of asymmetry throughout the gait cycle in relation to barefoot walking. Our results suggest that each orthosis position analysed in this study fulfills its protective function, but gait 15DF can lead to the overload of knee and hip joints.

Exercises in virtual reality (VR) have recently become a popular form of rehabilitation and are reported to be more effective than a standard rehabilitation protocol alone. The aim of this study was to assess the efficacy of adjunct VR training in improving postural control in patients after total knee replacement surgery (TKR). Forty-two patients within 7–14 days of TKR were enrolled and divided into a VR group and a control group (C). The C group underwent standard postoperative rehabilitation. The VR group additionally attended twelve 30-min exercise sessions using the Virtual Balance Clinic prototype system. Balance was assessed on the AMTI plate in bipedal standing with and without visual feedback before and after the four-week rehabilitation. Linear measures and sample entropy of CoP data were analyzed. After four weeks of rehabilitation, a significant reduction in parameters in the sagittal plane and ellipse area was noted while the eyes remained open. Regression analysis showed that sample entropy depended on sex, body weight, visual feedback and age. Based on the sample entropy results, it was concluded that the complexity of the body reaction had not improved. The standing-with-eyes-closed test activates automatic balance mechanisms and offers better possibilities as a diagnostic tool.

Human postural control is commonly assessed by center of pressure (CoP) displacement analysis. However, traditional linear parameters do not provide a complete picture of postural control, so a number of nonlinear analyses have been introduced. One of these is recurrence quantification analysis (RQA), which is used to determine the number and duration of repeated states in a dynamic system. This review aimed to show how the RQA measures look in different groups of subjects when assessing postural stability during quiet standing and how the authors interpret them. Therefore, a systematic review was conducted of papers published from 2000 to February 2023. Searched databases were PubMed, ScienceDirect, and EBSCO. Twenty-eight publications were included in this review. The RQA parameters most commonly found in papers are %DET (determinism), ENT (Shannon entropy), %REC (recurrence), and %LAM (laminarity). %LAM is the most sensitive factor in determining differences in CoP position between different age groups, as it describes motion fluidity. The vision affects the deterministic structure of CoP motions. When the sensory organization test conditions became difficult, CoP variability increased, while the %DET decreased. It was concluded that traditional and nonlinear methods provide complementary and not redundant information for assessing age- and health-related changes in standing balance.

This study aimed to assess the influence of leg dominance on the symmetry of body balance during one-leg standing tasks. Methods: Ninety-six healthy adults were enrolled in this study. Leg dominance was defined using Waterloo Footedness Questionnaire-Revised (WFQ-R) and body balance was measured in one-leg standing test on firm surface (eyes open and closed) and on the foam surface (eyes open). Symmetry Index (SI) of balance parameters was correlated with the results of WFQ-R. Results: The analysis showed that each participant had better test results for one leg compared to the other, and for most participants and test conditions, the more stable lower limb was the right one. No significant correlations were found between WFQ-R and SI. Conclusions: Leg dominance does not seem to affect the ability to maintain body balance on one leg standing on a stable or foam surface within the conditions tested in this study. Nevertheless, some asymmetry between right and left leg standing is visible in healthy adults.

Total knee replacement (TKR) is the treatment of choice for advanced stages of osteoarthritis but it requires good postoperative rehabilitation. This study aimed to assess the effectiveness of exercises using virtual reality to improve gait parameters in patients after TKR. Fifty-nine patients 7–14 days after TKR surgery were divided into a study group (VRG, n = 38) and a control group (CG, n = 21). Both groups underwent the same 4-week rehabilitation protocol. The VRG group had 12 additional nonimmersive virtual reality game sessions on the Virtual Balance Clinic prototype system at 30 min each, focusing on gait and balance improvement. Spatiotemporal, force and foot plantar pressure parameters were collected on an instrumented treadmill during a 30 s walk. The most significant improvement was in the symmetry indices of forefoot force, maximum forefoot force, loading response time, and preswing time (p < 0.05) in both groups. Gait speed increased by 31.25% and 44% in the VRG and CG groups, respectively (p < 0.005). However, the extra exergaming sessions did not significantly improve rehabilitation outcomes. Therefore, additional VR training does not improve gait better than standard rehabilitation alone, but the improvement of gait, especially its symmetry, is significant within the first six weeks after surgery.