Knee Osteoarthritis, Motor Control, Risk of Falls and Virtual Reality

The goal of this clinical trial is to learn about knee osteoarthritis, functionality, and risk of falls in community-dwelling adults aged 60 years and older. The main questions it aims to answer are:

* What are the characteristics of a community-dwelling population over 60 years and older in terms of knee osteoarthritis, functionality, and risk of falls?
* Does an intervention with virtual reality lower knee osteoarthritis symptoms, raise functionality and prevent falls in community-dwelling adults aged 60 years and older, compared to a control group receiving conventional physiotherapy treatment based on therapeutic exercise?

Participants will:

* Answer questionnaires.
* Perform physical laboratory tests through a camera-based motion capture system.
* Execute task-based exercises in a virtual environment through virtual reality.

Researchers will compare community-dwelling adults aged 60 years and older who execute task based exercises in a virtual environment through virtual reality and community-dwelling adults aged 60 years and older receiving conventional physiotherapy treatment based on therapeutic exercise to see if virtual reality improves knee osteoarthritis symptoms, functionality, and lowers fall risk.

Background

Knee osteoarthritis (OA) is prevalent among older adults, affecting a substantial proportion of this population and being linked to various functional impairments such as joint stiffness, reduced mobility, and chronic pain. More specifically, knee OA is one of the most disabling musculoskeletal conditions worldwide, leading to significant healthcare costs and economic burdens. Several studies have demonstrated a strong association between knee OA and falls in older adults. In particular, it has been observed that knee OA is a significant predictor of multiple falls and is closely related to deficits in balance and gait stability.

To properly understand the close relationship between knee OA and falls, it is crucial to consider motor control dysfunctions associated with joint pain and mechanical alterations, as they are often the primary triggers of falls. Research in this field highlights the importance of directing new studies toward functional tasks, as they represent the essence of motor control. Therefore, the observation and analysis of functional tasks are crucial for examining the motor control of older adults, being 3D motion capture systems the gold standard for the measurement and analysis of human movement.

On the other hand, new technologies such as immersive virtual reality (VR) are gaining recognition and popularity as treatment modalities. This is because they allow users to interact with environments and situations that simulate real life, offering activities tailored to their needs while avoiding the potential risks of the real world. Additionally, it provides an opportunity to repeat exercises, improve performance, and achieve effective learning.

Objectives Several objectives are outlined, as a comprehensive approach involving two different phases will be carried out.

* Phase 1 (Cross-Sectional Study) Main objective: to describe the population aged 60 and older living in the community in terms of knee osteoarthritis symptoms, functionality, and fall risk.
* Phase 2 (Experimental Study) Main objective: to assess the efficacy of a virtual reality intervention in a community-dwelling population aged 60 and above in terms of knee osteoarthritis symptoms improvement, functionality improvement, and fall risk reduction.

Methods

* Setting, locations and relevant dates: testing is going to be conducted in the Research Center for Information and Communication Technologies (CITIC) (A Coruña, Spain) and Senior University Center of the University of A Coruña (A Coruña, Spain).
* Data collection is planned for the months of May 2024 to May 2025.
* Participants: the recruitment of participants will be carried out through the dissemination of the study via informative posters distributed in the University of A Coruña, including the Senior University; in the network of civic centers in the city of A Coruña; as well as electronically through the researchers' social media networks (Twitter, Facebook, and Instagram). The participant information process, as well as the request for informed consent, will be conducted in the CITIC, after having answered the pre-selection questionnaires.
* Variables: see "outcomes measures".
* Study size: the sample size is estimated using the G-power program, indicating that the minimum number of participants needed to detect medium effect sizes, with a type I error probability of 0.05 and a power of 0.95, with an effect size of 0.7 and considering the analysis through the t-test: the difference between two independent means would be a total of 110 participants.
* Statistical analysis: a descriptive analysis will be performed to characterize the subjects in detail. Qualitative variables will be presented as absolute figures with their respective percentages, and quantitative variables as measures of central tendency (mean and median) and dispersion (standard deviation, minimum, and maximum values). The Kolmogorov-Smirnov test will be used to assess the normality of data distribution.

To explore significant differences between groups, a bivariate statistical analysis will be conducted. The Student's T-test for independent samples will be used for comparing means if the variables under consideration are normal; otherwise, the Mann-Whitney U test will be employed for non-normal variables. The chi-square statistic (X2) with a 95% confidence interval will be applied for the association of qualitative variables. The correlation between quantitative variables will be assessed using the Pearson or Spearman correlation coefficient. A significance level of p \< 0.05 will be considered. Data processing and analysis will be carried out using the statistical package SPSS, version 24.0 for Windows (Armonk, NY: IBM Corp.).

Eligibility Criteria:
Inclusion Criteria:

* Age over 60 years.
* Non-institutionalized individuals.
* Subjects who wish and consent through informed consent to participate in the study.
* Have the ability to walk independently (with or without assistive devices).
* Diagnosis of primary knee osteoarthritis according to the clinical and radiological criteria of the American College of Rheumatology.
* Specifically, for phase 1, subjects without a knee osteoarthritis diagnosis will also be included.

Exclusion Criteria:

* History of significant previous traumas or surgeries to the spine, pelvis, or legs in the last 12 months.
* Self-reported presence of dizziness, seizures, or epilepsy, aiming to prevent potential exacerbation of symptoms with VR.
* Vestibular disorders (balance).
* Neurological diseases, cardiovascular, or respiratory disorders affecting activity; as well as inflammatory or autoimmune diseases affecting the lower limb joints, and other forms of secondary osteoarthritis.
* Diagnosis of a terminal illness or a health condition that prevents attendance.
* To have a medical contraindication for exercise.
* Body Mass Index (BMI) ≥ 40