Introduction
Aging is a natural phenomenon influenced by biological, environmental, and psychological factors. As a result, significant changes occur in cells and tissues, leading to reduced efficiency and activity of organs and physiological processes [1]. One of the primary challenges faced by the elderly is chronic diseases, such as knee osteoarthritis [3]. This condition involves cartilage degradation and synovial inflammation, resulting in joint stiffness, swelling, pain, and reduced mobility [4]. The most common site of osteoarthritis is the knee joint [5]. Individuals with this condition face challenges, such as impaired proprioception and balance, which may lead to falls [7]. Accordingly, the present study assesses the effects of Fall-proof exercises on the balance system of elderly women with knee osteoarthritis.

Methods
This study was a semi-experimental intervention with a pre-test and post-test design with an applicable purpose. The research population comprised elderly women aged 60-75 years with knee osteoarthritis in Kerman City, Iran. Using G*Power software, version 3.1 and considering a repeated measures mixed statistical method, the sample size was determined to be 25 participants (effect size=0.4, significance level=0.05, statistical power=0.95). Volunteers were referred to a specialist to confirm the diagnosis of knee osteoarthritis. Initially, the Mini-BESTest was administered to assess balance indices for all participants. Subsequently, participants were randomly assigned to the fall-proof training group and the control group through a lottery. The participants in the experimental group performed Fall-proof exercises three times a week for eight weeks. During the study, the control group continued their usual daily activities without additional exercises. At the end of the intervention, all participants in both groups were reassessed. Data were analyzed using a repeated measures mixed-design test via the SPSS software, version 26 at a significance level of 0.05.

Results
To determine the homogeneity of demographic characteristics between groups, the independent t-test was applied. The results indicated no significant differences in age, height, body mass, body mass index, and osteoarthritis history between the groups (P>0.05). Furthermore, the homogeneity of pre-test scores on the Mini-BESTest and its subcategories was assessed using the independent t-test, revealing no significant differences between the experimental and control groups (P>0.05). In this study, given the assumptions were met, a parametric repeated measures analysis of variance was utilized (Table 1).


The results indicated a significant effect of time on the total Mini-BESTest scores (η²=0.69, P<0.001, F(1, 23)=51.42). Similarly, a significant effect of group was observed (η²=0.26, P=0.009, F(1, 23)=8.23).
Analysis of Mini-BESTest subcategories revealed that time had a significant effect on predictive scores (η²=0.31, P=0.004, F(1, 23)=10.25), while group effects were not significant (P=0.13, F(1, 23)=2.46). Time significantly impacted reactive postural control scores (η²=0.54, P<0.001, F(1, 23)=27.04), whereas group effects were non-significant (P=0.16, F(1, 23)=2.01). Additionally, significant effects of time (η²=0.38, P<0.001, F(1, 23)=14.15) and group (η²=0.25, P=0.010, F(1, 23)=7.94) were observed for dynamic gait scores.
Due to the non-normal distribution of sensory orientation data, Wilcoxon non-parametric tests were used to compare pre-test and post-test scores between groups. Results showed no significant differences in pre- and post-test sensory orientation scores in the control group (Z=0, P=1) or the experimental group (Z=1.41, P=0.15). However, the Mann-Whitney U test indicated significant differences in post-test sensory orientation scores between the experimental and control groups (U=37.5, P=0.026).

Conclusion
The findings suggest that eight weeks of Fall-proof exercises significantly improved Mini-BESTest scores, indicating enhanced balance in elderly women with knee osteoarthritis. Among the Mini-BESTest subcategories, predictive, reactive postural control, and dynamic gait scores significantly improved in the experimental group post-intervention. Furthermore, dynamic gait and sensory orientation scores differed significantly between the experimental and control groups. Considering the effectiveness and low cost of Fall-proof exercises, they are recommended to coaches and therapists for balance improvement and rehabilitation in elderly individuals with knee osteoarthritis.

Ethical Considerations
Compliance with ethical guidelines
This study was approved by the Research Ethics Committee of Shahid Bahonar University of Kerman, Kerman, Iran (Code: IR.UK.REC.1402.005).

Funding
This research did not receive any grant from funding agencies in the public, commercial, or non-profit sectors.

Authors' contributions
Conceptualization and methodology: Saeed Bahiraei, and Hadis Sheikh Shoaee; Statistical analysis: Saeed Bahiraei; Investigations: Hadis Sheikh Shoaee, and Marta Safavi; Initial draft preparation: Hadis Sheikh Shoaee; Review and editing: All authors; Resources: Hadis Sheikh Shoaee; Project administration: Saeed Bahiraei, and Marta Safavi.

Conflicts of interest
The authors declared no conflict of interest.

Acknowledgements
The authors express their gratitude to all individuals who contributed to the completion of this research.


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