Virtual Reality in Improving Anticipatory Postural Adjustments to Step Initiation in Individuals with Knee Osteoarthritis: A Randomized Controlled Trial

Background: Virtual reality (VR) has been suggested as a new therapeutic approach in various sectors of rehabilitation, including the treatment of patients with knee osteoarthritis (OA), and one of its treatment goals is to improve the gait pattern and walking ability of patients. Objective: This study aimed to evaluate if VR, along with conventional physiotherapy treatment (CT), has superior effects to kinesiotherapy alone on pain, physical capacity, balance, and the parameters of anticipatory postural adjustments (APAs) in patients with knee OA. Design: This study is a single-blind randomized controlled trial. Setting: Secondary care at Hospital SARAH Network of Rehabilitation Hospitals, Brazil. Participants: Forty participants (31 women and 9 men) with knee OA in at least one knee and able to ambulate independently. Intervention: A rehabilitation program (8 consecutive weeks, 50-minute session, twice a week). Patients were randomized into the intervention groups CT or VR. Main Outcome Measures: Primary-latency of APA, amplitude of APA, and time to reach the maximum acceleration amplitude. Secondary-balance control by Mini-Balance Evaluation Systems Test, pain, and physical capacity by Western Ontario and McMaster Universities Arthritis Index. Results: The results of the study showed that conventional treatment significantly improved pain intensity, physical capacity, and balance in individuals with knee OA; however, only the group that used VR showed improvement in the APA parameters. Conclusion: This study demonstrated that VR associated with conventional treatment improved APAs in patients with knee OA.

Wearable-based assessment of anticipatory postural adjustments during step initiation in patients with knee osteoarthritis

Older adults with moderate to severe knee osteoarthritis (KOA) exhibit adaptive strategy for initiating walking, known as anticipatory postural adjustments (APAs). While video motion kinematics has been the traditional way of measuring APAs, it can be difficult to transport and install, making it impractical for medical settings. Inertial sensors have become a more popular method for evaluating APAs, but no prior research has used accelerometers to measure gait initiation in individuals with KOA. The study aimed to assess the validity and reliability of a wearable accelerometer device for measuring APAs older adults with and without KOA. 25 individuals with KOA and 10 healthy individuals underwent evaluation using a wearable commercially available accelerometer (MetamotionC) and a video motion capture system. Reflective markers were placed on the lumbar vertebra and calcaneus. Participants were asked to initiate a step, and the researchers measured the APAlatency and APAamplitude of each subject. APAlatency showed an very large to almost perfect correlation in both groups (CG:r = 0.82; p = 0.003 and KOA r = 0.98; p < 0.00001) between the instruments, while APAamplitude had a moderate to very large correlation (CG: r = 0.65; p = 0.04and KOA: r = 0.80; p < 0.00001). Overall, the measurements showed fair to high reliability for intraclass correlation for video and accelerometer variables. Significant group effect was found for both variables: APAlatency (F1, 66 = 7.3; p = 0.008) and APAamplitude (F1,66 = 9.5; p = 0.00). The wearable tri-axial accelerometer is a valid and reliable for assessing APAs during gait initiation in individuals with KOA, and this population exhibits lower APAs when initiating a step.

Wearable Devices and Smartphone Inertial Sensors for Static Balance Assessment: A Concurrent Validity Study in Young Adult Population

Falls represent a public health issue around the world and prevention is an important part of the politics of many countries. The standard method of evaluating balance is posturography using a force platform, which has high financial costs. Other instruments, such as portable devices and smartphones, have been evaluated as low-cost alternatives to the screening of balance control. Although smartphones and wearables have different sizes, shapes, and weights, they have been systematically validated for static balance control tasks. Different studies have applied different experimental configurations to validate the inertial measurements obtained by these devices. We aim to evaluate the concurrent validity of a smartphone and a portable device for the evaluation of static balance control in the same group of participants. Twenty-six healthy and young subjects comprised the sample. The validity for static balance control evaluation of built-in accelerometers inside portable smartphone and wearable devices was tested considering force platform recordings as a gold standard for comparisons. A linear correlation (r) between the quantitative variables obtained from the inertial sensors and the force platform was used as an indicator of the concurrent validity. Reliability of the measures was calculated using Intraclass correlation in a subsample (n = 14). Smartphones had 11 out of 12 variables with significant moderate to very high correlation (r > 0.5, p < 0.05) with force platform variables in open eyes, closed eyes, and unipedal conditions, while wearable devices had 8 out of 12 variables with moderate to very high correlation (r > 0.5, p < 0.05) with force platform variables under the same task conditions. Significant reliabilities were found in closed eye conditions for smartphones and wearables. The smartphone and wearable devices had concurrent validity for the static balance evaluation and the smartphone had better validity results than the wearables for the static balance evaluation.